COMPUTECH

Many people are still unfamiliar with 3D printers, while those in the know are hailing them as a potential economic game changer. 3D printing is a method of making a solid object of almost any shape or size (depending on the size of the printer) by stacking up layers of material on top of each other.

The first 3D printer was created in 1984, but the growth in sales has risen dramatically in recent years. If there was any question before, we are certainly in the midst of the rise of 3D printers now. According to statistics from The Economist, the 3D printer market rose 29 percent in 2012 to $2.2 billion annually.

Interestingly, a large percentage of the items being built by 3D printers are still prototypes, with only about one in every four being items for production. Both of these categories have major impacts, though, as even using 3D printers on prototypes can significantly speed up the research and development process. As a result, ideas can become market-ready products faster. That gives companies a better chance of turning a profit on an idea, as less money has to go into it before it can be put on the market. In addition, more rapidly manufacturing products for the marketplace can lead to big gains in profit as well.

However, perhaps the most interesting impact that 3D printers can have is on the ability to customize products at little or no extra cost. For example, Nokia now offers a case that can be customized and produced through a 3D printer.

The array of items that can be made from a 3D printer includes car parts, fashion accessories, medical equipment and artificial organs, according to Forbes. One of the most incredible uses might be to 3D print organs for transplants, which then have live cells attached to them in order to grow.

(Above: The prints shown range in height from 19mm to 100mm
and have a layer thickness from 0.05mm to 0.4mm.)

The pricing of 3D printers is dropping, which means that small business owners may already be taking advantage of some of the opportunities that they present. Amazon is now offering 3D printers for under $1,000. This type of an affordable price point means that many entrepreneurs with big ideas can get their hands on 3D printers and brainstorm incredible new ideas.

Most likely, some of the first big success stories will involve the incredible levels of customization that can be undertaken with a 3D printer for little or no extra production cost. Because 3D printers enable the ability to slightly alter and re-print the same design rapidly, businesses can offer customized, tangible products for little extra cost. In addition, they can rapidly develop their own ideas, tweaking them at each step while keeping costs down and keeping the process moving along.

How to clean brass with natural ingredients.

2014-04-12T16:20:00.001-04:00

Though there are chemical brass cleaners on the market, however, you can use natural ingredients to clean brass, most of which you probably already have at home. Made from a combination of zinc and copper, brass is a popular metal found in cookware, jewelry, musical instruments (brass band, anyone?) and home decorative objects.
If your house is of a certain age, many of your doorknobs may be brass.

Like the metals from which it is made, brass also tarnishes easily. What is the best way to clean brass? First, you need to determine if your item is, in fact, made of brass. Hold a magnet to your item. If it sticks, the item is not brass, but most likely brass-plated. Use only water and mild detergent to clean brass-plated items, as anything more abrasive could damage the plating.

If you have a tarnished or dirty brass piece that needs cleaning, how you do so depends on whether it is lacquered – i.e. coated with a protective glossy finish – or non-lacquered brass. Lacquered brass can be cleaned simply by wiping with a damp cloth.

Cleaning non-lacquered brass requires more elbow grease. Though there are chemical brass cleaners on the market, try using some of these natural ingredients to clean brass, most of which you probably already have at home:

Ketchup: The housekeeping guru who has been writing the syndicated “Hints from Heloise” column for more than 30 years recommends this kitchen staple. Squirt some ketchup on a clean cloth and rub over tarnished brass. Then wipe clean with a damp cloth and buff dry.
Soap or Mild Detergent: If your brass item is dusty or dirty rather than tarnished, submerging it in warm soapy water and cleaning with a soft cloth could do the trick. Use a toothbrush to gently scrub extra dirty areas.
Vinegar, Salt and Flour: These versatile home staples can be combined to make a paste to clean tarnished brass. Dissolve 1 teaspoon of salt into one-half cup of vinegar, and add flour until the mixture becomes a paste. Rub into the brass, leave for about 10 minutes, then rinse with warm water and buff dry.
Water: Heat a pint of water, and add 2 tablespoons each of salt and white vinegar to create another natural recipe for polishing tarnished brass. Rub the mixture onto the brass, then dry with a clean rag.
Lemon Juice: Straight lemon juice can be used to clean brass and bring back shine. After cleaning with lemon juice, wipe with damp cloth and buff dry.

When might you want to leave your brass piece tarnished? If the brass is an antique, take it to an appraiser before attempting to clean it. The tarnish could add value to your piece, or detract from it if you disturb the item’s natural finish.

And if you are disappointed to discover that what you thought was brass is simply brass-plated? Take heart that it is easier to clean – and still can look as shiny as the real thing.

Great Red Spot.

2014-03-30T15:18:00.001-04:00

Cloud pattern on Jupiter in 2000.

The atmosphere of Jupiter is the largest planetary atmosphere in the Solar System. It is mostly made of molecular hydrogen and helium in roughly solar proportions; other chemical compounds are present only in small amounts and include methane, ammonia, hydrogen sulfide and water.
Although water is thought to reside deep in the atmosphere, its directly measured concentration is very low. The oxygen, nitrogen, sulfur, and noble gas abundances in Jupiter's atmosphere exceed solar values by a factor of about three.

The atmosphere of Jupiter lacks a clear lower boundary and gradually transitions into the liquid interior of the planet. From lowest to highest, the atmospheric layers are the troposphere, stratosphere, thermosphere and exosphere. Each layer has characteristic temperature gradients. The lowest layer, the troposphere, has a complicated system of clouds and hazes, comprising layers of ammonia, ammonium hydrosulfide and water. The upper ammonia clouds visible at Jupiter's surface are organized in a dozen zonal bands parallel to the equator and are bounded by powerful zonal atmospheric flows (winds) known as jets. The bands alternate in color: the dark bands are called belts, while light ones are called zones. Zones, which are colder than belts, correspond to upwellings, while belts mark descending air. The zones' lighter color is believed to result from ammonia ice; what gives the belts their darker colors is not known with certainty. The origins of the banded structure and jets are not well understood, though two models exist. The shallow model holds that they are surface phenomena overlaying a stable interior. In the deep model, the bands and jets are just surface manifestations of deep circulation in Jupiter's mantle of molecular hydrogen, which is organized into cylinders.

The Jovian atmosphere shows a wide range of active phenomena, including band instabilities, vortices (cyclones and anticyclones), storms and lightning. The vortices reveal themselves as large red, white or brown spots (ovals). The largest two spots are the Great Red Spot (GRS) and Oval BA, which is also red. These two and most of the other large spots are anticyclonic. Smaller anticyclones tend to be white. Vortices are thought to be relatively shallow structures with depths not exceeding several hundred kilometers. Located in the southern hemisphere, the GRS is the largest known vortex in the Solar System. It could engulf several Earths and has existed for at least three hundred years. Oval BA, south of GRS, is a red spot a third the size of GRS that formed in 2000 from the merging of three white ovals.

Jupiter has powerful storms, always accompanied by lightning strikes. The storms are a result of moist convection in the atmosphere connected to the evaporation and condensation of water. They are sites of strong upward motion of the air, which leads to the formation of bright and dense clouds. The storms form mainly in belt regions. The lightning strikes on Jupiter are more powerful than those on Earth. However, there are fewer of them, and the average levels of lightning activity are comparable to those on Earth.

Vertical structure

The atmosphere of Jupiter is classified into four layers, by increasing altitude: the troposphere, stratosphere, thermosphere and exosphere. Unlike the Earth's atmosphere, Jupiter's lacks a mesosphere. Jupiter does not have a solid surface, and the lowest atmospheric layer, the troposphere, smoothly transitions into the planet's fluid interior. This is a result of having temperatures and the pressures well above those of the critical points for hydrogen and helium, meaning that there is no sharp boundary between gas and liquid phases. Hydrogen becomes a supercritical fluid at around 12 bars pressure.

Vertical structure of the atmosphere of Jupiter. Note that the pressure drops together with altitude. The Galileo atmospheric probe stopped transmitting at a depth of 132 km below the 1 bar "surface" of Jupiter.

Since the lower boundary of the atmosphere is ill-defined, the pressure level of 10 bars, at an altitude of about 90 km below the 1 bar with a temperature of around 340 K, is commonly treated as the base of the troposphere. In scientific literature, the 1 bar pressure level is usually chosen as a zero point for altitudes—a "surface" of Jupiter. As with Earth, the top atmospheric layer, the exosphere, does not have a well defined upper boundary. The density gradually decreases until it smoothly transitions into the interplanetary medium approximately 5,000 km above the "surface".

The vertical temperature variations in the Jovian atmosphere are similar to those of the atmosphere of Earth. The temperature of the troposphere decreases with height until it reaches a minimum at the tropopause, which is the boundary between the troposphere and stratosphere. On Jupiter, the tropopause is approximately 50 km above the visible clouds (or 1 bar level), where the pressure and temperature are about 0.1 bar and 110 K. In the stratosphere, the temperatures rise to about 200 K at the transition into the thermosphere, at an altitude and pressure of around 320 km and 1 μbar. In the thermosphere, temperatures continue to rise, eventually reaching 1000 K at about 1000 km, where pressure is about 1 nbar.

Jupiter's troposphere contains a complicated cloud structure. The upper clouds, located in the pressure range 0.6–0.9 bar, are made of ammonia ice. Below these ammonia ice clouds, denser clouds made of ammonium hydrosulfide or ammonium sulfide (between 1–2 bar) and water (3–7 bar) are thought to exist. There are no methane clouds as the temperatures are too high for it to condense. The water clouds form the densest layer of clouds and have the strongest influence on the dynamics of the atmosphere. This is a result of the higher condensation heat of water and higher water abundance as compared to the ammonia and hydrogen sulfide (oxygen is a more abundant chemical element than either nitrogen or sulfur). Various tropospheric (at 200–500 mbar) and stratospheric (at 10–100 mbar) haze layers reside above the main cloud layers. The latter are made from condensed heavy polycyclic aromatic hydrocarbons or hydrazine, which are generated in the upper stratosphere (1–100 μbar) from methane under the influence of the solar ultraviolet radiation (UV). The methane abundance relative to molecular hydrogen in the stratosphere is about 10−4, while the abundance ratio of other light hydrocarbons, like ethane and acetylene, to molecular hydrogen is about 10−6.

Jupiter's thermosphere is located at pressures lower than 1 μbar and demonstrates such phenomena as airglow, polar aurorae and X-ray emissions. Within it lie layers of increased electron and ion density that form the ionosphere. The high temperatures prevalent in the thermosphere (800–1000 K) have not been fully explained yet; existing models predict a temperature no higher than about 400 K. They may be caused by absorption of high-energy solar radiation (UV or X-ray), by heating from the charged particles precipitating from the Jovian magnetosphere, or by dissipation of upward-propagating gravity waves. The thermosphere and exosphere at the poles and at low latitudes emit X-rays, which were first observed by the Einstein Observatory in 1983. The energetic particles coming from Jupiter's magnetosphere create bright auroral ovals, which encircle the poles. Unlike their terrestrial analogs, which appear only during magnetic storms, aurorae are permanent features of Jupiter's atmosphere. The thermosphere was the first place outside the Earth where the trihydrogen cation (H+
3) was discovered. This ion emits strongly in the mid-infrared part of the spectrum, at wavelengths between 3 and 5 μm; this is the main cooling mechanism of the thermosphere.

Chemical composition

The composition of Jupiter's atmosphere is similar to that of the planet as a whole. Jupiter's atmosphere is the most comprehensively understood of those of all the gas giants because it was observed directly by the Galileo atmospheric probe when it entered the Jovian atmosphere on December 7, 1995. Other sources of information about Jupiter's atmospheric composition include the Infrared Space Observatory (ISO), the Galileo and Cassini orbiters, and Earth-based observations.

The two main constituents of the Jovian atmosphere are molecular hydrogen (H
2) and helium. The helium abundance is 0.157 ± 0.0036 relative to molecular hydrogen by number of molecules, and its mass fraction is 0.234 ± 0.005, which is slightly lower than the Solar System's primordial value. The reason for this low abundance is not entirely understood, but some of the helium may have condensed into the core of Jupiter. This condensation is likely to be in the form of helium rain: as hydrogen turns into the metallic state at the depths of more than 10,000 km, helium separates from it forming droplets which, being denser than the metallic hydrogen, descend to the core. This can also explain the severer depletion of neon (see Table), which easily dissolves in helium droplets and is transported in them to the core as well.

The atmosphere contains various simple compounds such as water, methane (CH4), hydrogen sulfide (H2S), ammonia (NH3) and phosphine (PH3). Their abundances in the deep (below 10 bar) troposphere imply that the atmosphere of Jupiter is enriched in the elements carbon, nitrogen, sulfur and possibly oxygen by factor of 2–4 relative to the Sun. The noble gases argon, krypton and xenon appear to be enriched relative to solar abundances as well (see table), while neon is scarcer. Other chemical compounds such as arsine (AsH3) and germane (GeH4) are present only in trace amounts. The upper atmosphere of Jupiter contains small amounts of simple hydrocarbons such as ethane, acetylene, and diacetylene, which form from methane under the influence of the solar ultraviolet radiation and charged particles coming from Jupiter's magnetosphere. The carbon dioxide, carbon monoxide and water present in the upper atmosphere are thought to originate from impacting comets, such as Shoemaker-Levy 9. The water cannot come from the troposphere because the cold tropopause acts like a cold trap, effectively preventing water from rising to the stratosphere (see Vertical structure above).

Earth- and spacecraft-based measurements have led to improved knowledge of the isotopic ratios in Jupiter's atmosphere. As of July 2003, the accepted value for the deuterium abundance is 2.25 ± 0.35 × 10−5, which probably represents the primordial value in the protosolar nebula that gave birth to the Solar System. The ratio of nitrogen isotopes in the Jovian atmosphere, 15N to 14N, is 2.3 × 10−3, a third lower than that in the Earth's atmosphere (3.5 × 10−3). The latter discovery is especially significant since the previous theories of Solar System formation considered the terrestrial value for the ratio of nitrogen isotopes to be primordial.

Zones, belts and jets

The visible surface of Jupiter is divided into several bands parallel to the equator. There are two types of bands: lightly colored zones and relatively dark belts. The wide Equatorial Zone (EZ) extends between latitudes of approximately 7°S to 7°N. Above and below the EZ, the North and South Equatorial belts (NEB and SEB) extend to 18°N and 18°S, respectively. Farther from the equator lie the North and South Tropical zones (NtrZ and STrZ). The alternating pattern of belts and zones continues until the polar regions at approximately 50 degrees latitude, where their visible appearance becomes somewhat muted. The basic belt-zone structure probably extends well towards the poles, reaching at least to 80° North or South.

The most detailed map of Jupiter ever produced; taken by Cassini

The difference in the appearance between zones and belts is caused by differences in the opacity of the clouds. Ammonia concentration is higher in zones, which leads to the appearance of denser clouds of ammonia ice at higher altitudes, which in turn leads to their lighter color. On the other hand, in belts clouds are thinner and are located at lower altitudes. The upper troposphere is colder in zones and warmer in belts. The exact nature of chemicals that make Jovian zones and bands so colorful is not known, but they may include complicated compounds of sulfur, phosphorus and carbon.

The Jovian bands are bounded by zonal atmospheric flows (winds), called jets. The eastward (prograde) jets are found at the transition from zones to belts (going away from the equator), whereas westward (retrograde) jets mark the transition from belts to zones. Such flow velocity patterns mean that the zonal winds decrease in belts and increase in zones from the equator to the pole. Therefore wind shear in belts is cyclonic, while in zones it is anticyclonic. The EZ is an exception to this rule, showing a strong eastward (prograde) jet and has a local minimum of the wind speed exactly at the equator. The jet speeds are high on Jupiter, reaching more than 100 m/s. These speeds correspond to ammonia clouds located in the pressure range 0.7–1 bar. The prograde jets are generally more powerful than the retrograde jets. The vertical extent of jets is not known. They decay over two to three scale heights[a] above the clouds, while below the cloud level, winds increase slightly and then remain constant down to at least 22 bar—the maximum operational depth reached by the Galileo probe.

Zonal wind speeds in the atmosphere of Jupiter

The origin of Jupiter's banded structure is not completely clear, though it may be similar to that driving the Earth's Hadley cells. The simplest interpretation is that zones are sites of atmospheric upwelling, whereas belts are manifestations of downwelling. When air enriched in ammonia rises in zones, it expands and cools, forming high and dense clouds. In belts, however, the air descends, warming adiabatically, and white ammonia clouds evaporate, revealing lower, darker clouds. The location and width of bands, speed and location of jets on Jupiter are remarkably stable, having changed only slightly between 1980 and 2000. One example of change is a decrease of the speed of the strongest eastward jet located at the boundary between the North Tropical zone and North Temperate belts at 23°N. However bands vary in coloration and intensity over time (see below).

Specific bands

The belts and zones that divide Jupiter's atmosphere each have their own names and unique characteristics. They begin below the North and South Polar Regions, which extend from the poles to roughly 40–48° N/S. These bluish-gray regions are usually featureless.

The North North Temperate Region rarely shows more detail than the polar regions, due to limb darkening, foreshortening, and the general diffuseness of features. That said, the North-North Temperate Belt (NNTB) is the northernmost distinct belt, though it occasionally disappears. Disturbances tend to be minor and short-lived. The North-North Temperate Zone (NNTZ) is perhaps more prominent, but also generally quiet. Other minor belts and zones in the region are occasionally observed.

Idealized illustration of Jupiter's cloud bands, labeled with their official abbreviations. Lighter zones are indicated to the right, darker belts to the left. The Great Red Spot and Oval BA are shown in the South Tropical Zone and South Temperate Belt, respectively.

The North Temperate Region is part of a latitudinal region easily observable from Earth, and thus has a superb record of observation. It also features the strongest prograde jet stream on the planet—a westerly current that forms the southern boundary of the North Temperate Belt (NTB). The NTB fades roughly once a decade (this was the case during the Voyager encounters), making the North Temperate Zone (NTZ) apparently merge into the North Tropical Zone (NTropZ). Other times, the NTZ is divided by a narrow belt into northern and southern components.

The North Tropical Region is composed of the NTropZ and the North Equatorial Belt (NEB). The NTropZ is generally stable in coloration, changing in tint only in tandem with activity on the NTB's southern jet stream. Like the NTZ, it too is sometimes divided by a narrow band, the NTropB. On rare occasions, the southern NTropZ plays host to "Little Red Spots". As the name suggests, these are northern equivalents of the Great Red Spot. Unlike the GRS, they tend to occur in pairs and are always short-lived, lasting a year on average; one was present during the Pioneer 10 encounter.

The NEB is one of the most active belts on the planet. It is characterized by anticyclonic white ovals and cyclonic "barges" (also known as "brown ovals"), with the former usually forming farther north than the latter; as in the NTropZ, most of these features are relatively short-lived. Like the South Equatorial Belt (SEB), the NEB has sometimes dramatically faded and "revived". The timescale of these changes is about 25 years.

The Equatorial Region (EZ) is one of the more stable regions of the planet, in latitude and in activity. The northern edge of the EZ hosts spectacular plumes that trail southwest from the NEB, which are bounded by dark, warm (in infrared) features known as festoons (hot spots). Though the southern boundary of the EZ is usually quiescent, observations from the late 19th into the early 20th century show that this pattern was then reversed relative to today. The EZ varies considerably in coloration, from pale to an ochre, or even coppery hue; it is occasionally divided by an Equatorial Band (EB). Features in the EZ move roughly 390 km/h relative to the other latitudes.

Zones, belts and vortices on Jupiter. The wide equatorial zone is visible in the center surrounded by two dark equatorial belts (SEB and NEB). The large grayish-blue irregular "hot spots" at the northern edge of the white Equatorial Zone change over the course of time as they march eastward across the planet. The Great Red Spot is at the southern margin of the SEB. Strings of small storms rotate around northern-hemisphere ovals. Small, very bright features, possible lightning storms, appear quickly and randomly in turbulent regions. The smallest features visible at the equator are about 600 kilometers across. This 14-frame animation spans 24 Jovian days, or about 10 Earth days. The passage of time is accelerated by a factor of 600,000.

The South Tropical Region includes the South Equatorial Belt (SEB) and the South Tropical Zone. It is by far the most active region the planet, as it is home to its strongest retrograde jet stream. The SEB is usually the broadest, darkest belt on Jupiter; it is sometimes split by a zone (the SEBZ), and can fade entirely every 3 to 15 years before reappearing in what is known as an SEB Revival cycle. A period of weeks or months following the belt's disappearance, a white spot forms and erupts dark brownish material which is stretched into a new belt by Jupiter's winds. The belt most recently disappeared in May 2010.[40] Another characteristic of the SEB is a long train of cyclonic disturbances following the Great Red Spot. Like the NTropZ, the STropZ is one of the most prominent zones on the planet; not only does it contain the GRS, but it is occasionally rent by a South Tropical Disturbance (STropD), a division of the zone that can be very long-lived; the most famous one lasted from 1901 to 1939.

The South Temperate Region, or South Temperate Belt (STB), is yet another dark, prominent belt, more so than the NTB; until March 2000, its most famous features were the long-lived white ovals BC, DE, and FA, which have since merged to form Oval BA ("Red Jr."). The ovals were part of South Temperate Zone, but they extended into STB partially blocking it. The STB has occasionally faded, apparently due to complex interactions between the white ovals and the GRS. The appearance of the South Temperate Zone (STZ)—the zone in which the white ovals originated—is highly variable.

There are other features on Jupiter that are either temporary or difficult to observe from Earth. The South South Temperate Region is harder to discern even than the NNTR; its detail is subtle and can only be studied well by large telescopes or spacecraft. Many zones and belts are more transient in nature and are not always visible. These include the Equatorial band (EB), North Equatorial belt zone (NEBZ, a white zone within the belt) and South Equatorial belt zone (SEBZ). Belts are also occasionally split by a sudden disturbance. When a disturbance divides a normally singular belt or zone, an N or an S is added to indicate whether the component is the northern or southern one; e.g., NEB(N) and NEB(S).

Dynamics

2009

Circulation in Jupiter's atmosphere is markedly different from that in the atmosphere of Earth. The interior of Jupiter is fluid and lacks any solid surface. Therefore, convection may occur throughout the planet's outer molecular envelope. As of 2008, a comprehensive theory of the dynamics of the Jovian atmosphere has not been developed. Any such theory needs to explain the following facts: the existence of narrow stable bands and jets that are symmetric relative to Jupiter's equator, the strong prograde jet observed at the equator, the difference between zones and belts, and the origin and persistence of large vortices such as the Great Red Spot.

The theories regarding the dynamics of the Jovian atmosphere can be broadly divided into two classes: shallow and deep. The former hold that the observed circulation is largely confined to a thin outer (weather) layer of the planet, which overlays the stable interior. The latter hypothesis postulates that the observed atmospheric flows are only a surface manifestation of deeply rooted circulation in the outer molecular envelope of Jupiter. As both theories have their own successes and failures, many planetary scientists think that the true theory will include elements of both models.

Shallow models

The first attempts to explain Jovian atmospheric dynamics date back to the 1960s. They were partly based on terrestrial meteorology, which was well developed at that time. Those shallow models assumed that the jets on Jupiter are driven by small scale turbulence, which is in turn maintained by moist convection in the outer layer of the atmosphere (above the water clouds). The moist convection is a phenomenon related to the condensation and evaporation of water and is one of the major drivers of terrestrial weather. The production of the jets in this model is related to a well-known property of two dimensional turbulence—the so-called inverse cascade, in which small turbulent structures (vortices) merge to form larger ones. The finite size of the planet means that the cascade can not produce structures larger than some characteristic scale, which for Jupiter is called the Rhines scale. Its existence is connected to production of Rossby waves. This process works as follows: when the largest turbulent structures reach a certain size, the energy begins to flow into Rossby waves instead of larger structures, and the inverse cascade stops. Since on the spherical rapidly rotating planet the dispersion relation of the Rossby waves is anisotropic, the Rhines scale in the direction parallel to the equator is larger than in the direction orthogonal to it. The ultimate result of the process described above is production of large scale elongated structures, which are parallel to the equator. The meridional extent of them appears to match the actual width of jets. Therefore in shallow models vortices actually feed the jets and should disappear by merging into them.

While these weather–layer models can successfully explain the existence of a dozen narrow jets, they have serious problems. A glaring failure of the model is the prograde (super-rotating) equatorial jet: with some rare exceptions shallow models produce a strong retrograde (subrotating) jet, contrary to observations. In addition, the jets tend to be unstable and can disappear over time. Shallow models cannot explain how the observed atmospheric flows on Jupiter violate stability criteria. More elaborated multilayer versions of weather–layer models produce more stable circulation, but many problems persist. Meanwhile, the Galileo probe found that the winds on Jupiter extend well below the water clouds at 5–7 bar and do not show any evidence of decay down to 22 bar pressure level, which implies that circulation in the Jovian atmosphere may in fact be deep.

Deep models

The deep model was first proposed by Busse in 1976. His model was based on another well-known feature of fluid mechanics, the Taylor–Proudman theorem. It holds that in any fast-rotating barotropic ideal liquid, the flows are organized in a series of cylinders parallel to the rotational axis. The conditions of the theorem are probably met in the fluid Jovian interior. Therefore the planet's molecular hydrogen mantle may be divided into cylinders, each cylinder having a circulation independent of the others. Those latitudes where the cylinders' outer and inner boundaries intersect with the visible surface of the planet correspond to the jets; the cylinders themselves are observed as zones and belts.

Thermal image of Jupiter obtained by NASA Infrared Telescope Facility

The deep model easily explains the strong prograde jet observed at the equator of Jupiter; the jets it produces are stable and do not obey the 2D stability criterion. However it has major difficulties; it produces a very small number of broad jets, and realistic simulations of 3D flows are not possible as of 2008, meaning that the simplified models used to justify deep circulation may fail to catch important aspects of the fluid dynamics within Jupiter. One model published in 2004 successfully reproduced the Jovian band-jet structure. It assumed that the molecular hydrogen mantle is thinner than in all other models; occupying only the outer 10% of Jupiter's radius. In standard models of the Jovian interior, the mantle comprises the outer 20–30%. The driving of deep circulation is another problem. The deep flows can be caused both by shallow forces (moist convection, for instance) or by deep planet-wide convection that transports heat out of the Jovian interior. Which of these mechanisms is more important is not clear yet.

Internal heat

As has been known since 1966, Jupiter radiates much more heat than it receives from the Sun. It is estimated that the ratio between the power emitted by the planet and that absorbed from the Sun is 1.67 ± 0.09. The internal heat flux from Jupiter is 5.44 ± 0.43 W/m2, whereas the total emitted power is 335 ± 26 petawatts. The latter value is approximately equal to one billionth of the total power radiated by the Sun. This excess heat is mainly the primordial heat from the early phases of Jupiter's formation, but may result in part from the precipitation of helium into the core.

The internal heat may be important for the dynamics of the Jovian atmosphere. While Jupiter has a small obliquity of about 3°, and its poles receive much less solar radiation than its equator, the tropospheric temperatures do not change appreciably from the equator to poles. One explanation is that Jupiter's convective interior acts like a thermostat, releasing more heat near the poles than in the equatorial region. This leads to a uniform temperature in the troposphere. While heat is transported from the equator to the poles mainly via the atmosphere on Earth, on Jupiter deep convection equilibrates heat. The convection in the Jovian interior is thought to be driven mainly by the internal heat.

Discrete features

Vortices

The atmosphere of Jupiter is home to hundreds of vortices—circular rotating structures that, as in the Earth's atmosphere, can be divided into two classes: cyclones and anticyclones. Cyclones rotate in the direction similar to the rotation of the planet (counterclockwise in the northern hemisphere and clockwise in the southern); the anticyclones rotate in the reverse direction. However a major difference from the terrestrial atmosphere is that, in the Jovian atmosphere, anticyclones dominate over cyclones, as more than 90% of vortices larger than 2000 km in diameter are anticyclones. The lifetime of vortices varies from several days to hundreds of years depending on their size. For instance, the average lifetime of anticyclones with diameters from 1000 to 6000 km is 1–3 years. Vortices have never been observed in the equatorial region of Jupiter (within 10° of latitude), where they are unstable. As on any rapidly rotating planet, Jupiter's anticyclones are high pressure centers, while cyclones are low pressure.

New Horizons IR view of Jupiter's atmosphere

The anticyclones in Jupiter's atmosphere are always confined within zones, where the wind speed increases in direction from the equator to the poles. They are usually bright and appear as white ovals. They can move in longitude, but stay at approximately the same latitude as they are unable to escape from the confining zone. The wind speeds at their periphery are about 100 m/s. Different anticyclones located in one zone tend to merge, when they approach each other. However Jupiter has two anticyclones that are somewhat different from all others. They are the Great Red Spot (GRS) and the Oval BA; the latter formed only in 2000. In contrast to white ovals, these structures are red, arguably due to dredging up of red material from the planet's depths. On Jupiter the anticyclones usually form through merges of smaller structures including convective storms (see below), although large ovals can result from the instability of jets. The latter was observed in 1938–1940, when a few white ovals appeared as a result of instability of the southern temperate zone; they later merged to form Oval BA.

In contrast to anticyclones, the Jovian cyclones tend to be small, dark and irregular structures. Some of the darker and more regular features are known as brown ovals (or badges). However the existence of a few long–lived large cyclones has been suggested. In addition to compact cyclones, Jupiter has several large irregular filamentary patches, which demonstrate cyclonic rotation. One of them is located to the west of the GRS (in its wake region) in the southern equatorial belt. These patches are called cyclonic regions (CR). The cyclones are always located in the belts and tend to merge when they encounter each other, much like anticyclones.

The deep structure of vortices is not completely clear. They are thought to be relatively thin, as any thickness greater than about 500 km will lead to instability. The large anticyclones are known to extend only a few tens of kilometers above the visible clouds. The early hypothesis that the vortices are deep convective plumes (or convective columns) as of 2008 is not shared by the majority of planetary scientists.

Great Red Spot

The Great Red Spot (GRS) is a persistent anticyclonic storm, 22° south of Jupiter's equator; Earth observations establish a minimum storm lifetime of, variously, 183 years to possibly 348 years. The storm is large enough to be visible through Earth-based telescopes, first being observed by Samuel Heinrich Schwabe in 1831 as a drawing of the gap formed around it, and possibly even earlier, as a "permanent spot" was described by Gian Domenico Cassini between 1665 and 1713. The actual spot has been continually described and observed since Carr Walter Pritchett did so in 1878.

An infrared image of GRS (top) and Oval BA (lower left) showing its cool center, taken by the ground based Very Large Telescope. An image made by the Hubble Space Telescope (bottom) is shown for comparison.

The GRS rotates anticlockwise, with a period of about six Earth days or 14 Jovian days. Its dimensions are 24–40,000 km west–to–east and 12–14,000 km south–to–north. The spot is large enough to contain two or three planets the size of Earth. At the start of 2004, the Great Red Spot had approximately half the longitudinal extent it had a century ago, when it was 40,000 km in diameter. At the present rate of reduction it could potentially become circular by 2040, although this is unlikely because of the distortion effect of the neighboring jet streams. It is not known how long the spot will last, or whether the change is a result of normal fluctuations.

According to a study by scientists at the University of California, Berkeley, between 1996 and 2006 the spot lost 15 percent of its diameter along its major axis. Xylar Asay-Davis, who was on the team that conducted the study, noted that the spot is not disappearing because "[v]elocity is a more robust measurement because the clouds associated with the Red Spot are also strongly influenced by numerous other phenomena in the surrounding atmosphere."

Infrared data have long indicated that the Great Red Spot is colder (and thus, higher in altitude) than most of the other clouds on the planet; the cloudtops of the GRS are about 8 km above the surrounding clouds. Furthermore, careful tracking of atmospheric features revealed the spot's counterclockwise circulation as far back as 1966—observations dramatically confirmed by the first time-lapse movies from the Voyager flybys. The spot is spatially confined by a modest eastward jet stream (prograde) to its south and a very strong westward (retrograde) one to its north. Though winds around the edge of the spot peak at about 120 m/s (432 km/h), currents inside it seem stagnant, with little inflow or outflow. The rotation period of the spot has decreased with time, perhaps as a direct result of its steady reduction in size. In 2010, astronomers imaged the GRS in the far infrared (from 8.5 to 24 μm) with a spatial resolution higher than ever before and found that its central, reddest region is warmer than its surroundings by between 3–4 K. The warm airmass is located in the upper troposphere in the pressure range of 200–500 mbar. This warm central spot slowly counter-rotates and may be caused by a weak subsidence of air in the center of GRS.

The Great Red Spot's latitude has been stable for the duration of good observational records, typically varying by about a degree. Its longitude, however, is subject to constant variation. Because Jupiter does not rotate uniformly at all latitudes, astronomers have defined three different systems for defining the longitude. System II is used for latitudes of more than 10°, and was originally based on the average rotation rate of the Great Red Spot of 9h 55m 42s. Despite this, the spot has "lapped" the planet in System II at least 10 times since the early 19th century. Its drift rate has changed dramatically over the years and has been linked to the brightness of the South Equatorial Belt, and the presence or absence of a South Tropical Disturbance.

Approximate size comparison of Earth superimposed on this Dec 29, 2000 image showing the Great Red Spot

It is not known exactly what causes the Great Red Spot's reddish color. Theories supported by laboratory experiments suppose that the color may be caused by complex organic molecules, red phosphorus, or yet another sulfur compound. The Great Red Spot (GRS) varies greatly in hue, from almost brick-red to pale salmon, or even white. The reddest central region is slightly warmer than the surroundings, which is the first evidence that the Spot's color is affected by environmental factors. The spot occasionally disappears from the visible spectrum, becoming evident only through the Red Spot Hollow, which is its niche in the South Equatorial Belt (SEB). The visibility of GRS is apparently coupled to the appearance of the SEB; when the belt is bright white, the spot tends to be dark, and when it is dark, the spot is usually light. The periods when the spot is dark or light occur at irregular intervals; as of 1997, during the preceding 50 years, the spot was darkest in the periods 1961–66, 1968–75, 1989–90, and 1992–93.

The Great Red Spot should not be confused with the Great Dark Spot, a feature observed near the northern pole of Jupiter in 2000 by the Cassini–Huygens spacecraft. A feature in the atmosphere of Neptune was also called the Great Dark Spot. The latter feature, imaged by Voyager 2 in 1989, may have been an atmospheric hole rather than a storm. It was no longer present in 1994, although a similar spot had appeared farther to the north.

14 Google Application Resources.

2014-03-24T23:01:00.000-04:00

Google has an abundance of other resources that may not be as popular but still good to know. Here are some lesser-known Google tools and applications that could help you cope with the loss of Reader and add to your Google experience.

1. Google Ngram Viewer

Google's Ngram Viewer lets you search keywords in millions of books over the span of half a millennium, a useful tool for finding trends over time.
For power users, the Ngram Viewer also has advanced options, such as searching for particular keywords as specific parts of speech or combining keywords. Just in case you ever wanted to see how big cocaine was in Victorian times, now you can.

2. Google Correlate

A part of Google Trends, Google Correlate allows you to look at search trends over time. For example, input "soup" and you'll see a clear increase in searches during the winter months. The more fascinating part of Google Correlate is the Search by Drawing function. Draw a fun graph and Correlate will give you search keywords that best match your graph creation.

3. Google Trends

Look at trends in hot searches with Google Trends. Browse by date, or look at top searches in different categories with the new Top Charts function. Finally, with the Explore function, input a search term and see how it trended over time and location. You can also now view popular searches in a colorful fullscreen format.

4. Google Think Insights

Home to an abundance of resources, Google Think Insights is a useful tool for entrepreneurs and industry professionals. There are case studies, new findings and tips on how to grow your business, as well as showcases of exemplary projects. Finally, there are also tools for maximizing your site analytics and ad campaigns. A particularly useful collection is how to "Make Your Website Work Across Different Platforms."

5. Google Public Data Explorer

Search through databases from around the world, including the World Bank, OECD, Eurostat and the U.S. Census Bureau. After you find what you want, filter through categories to make graphs with the axes you want. Google's Public Data Explorer then displays the data in a line graph, bar graph, scatterplot or on a map.

6. Full Value of Mobile

A useful calculator for businesses, Google's Full Value of Mobile will calculate just how much having a mobile site is worth. The tool will help you analyze how customers interact with the various aspects of your business, from mobile sites to calls to cross-device ability.

7. Get Your Business Online

Get Your Business Online is Google's initiative to get more local businesses on the web, in an effort to boost the local economy as well as help small businesses grow. The initiative also encourages people to get other businesses online, with an end goal of reaching every local business in America. There are also listings for events and lessons. The free service also includes hosting for one year.

8. Webmaster Tools

Google's Webmaster Tools allows webmasters to monitor a site's health and traffic. Additional tools include a Structure Data Markup Helper and Google Places for Business.

9. Schemer

Schemer is like a combination to-do list and social event planning app. Connect via your Google+ account, enter your preferences, and Schemer will offer some things to do around your area. A great tool for travelers who want to make the most out of a visit, as well as for locals who want to find something to do on an otherwise boring day. You can also collaborate with the friends in your Google+ Circles and see who wants to do the same things as you.

10. Google Fonts

Google Fonts offers open source web fonts for all to use privately or commercially. As of now, there are 629 font families available. Filter fonts by thickness, slant, width and script.

11. Google Developers

Google Developers houses a plethora of resources that developers can use, tools such as internationalizing different websites and live presentations of tutorials. Developers can also join groups in a local area for meetups and collaboration.

12. Dart

Dart is a programming language developed by Google in hopes of eventually replacing JavaScript as the language of modern web apps. Dart was released in 2011 and is still in its development stages. With a goal to make coding and collaboration simpler, Dart was designed to be simple enough that even beginning developers could learn from it.

13. Google Keep

Launched earlier this year, Google Keep app connects to your Google Drive. Sync-able across all your devices, Google Keep allows you to keep notes, voice memos, pictures and checklists in order. The easy-to-use interface is a simple app for those looking to do basic note-keeping on-the-go.

14. Google Sky

A part of Google Earth, Google Sky allows you to explore space and star systems. In collaboration with NASA, using images from the Hubble Telescope, Google Sky is one of three subsidiaries of Google Earth, the others being Google Mars and Google Moon.

Biggest physics neutrinos experiments ever built.

2014-02-14T18:41:00.000-05:00

US researchers have given details of a plan for one of the biggest physics experiments ever built.

Scientists at Fermilab, just outside Chicago, want to fire a beam of particles called neutrinos through 1,300km (800 miles) of rock some 30km below the surface.

The experiment's aim is to learn more about how the Universe was created.

BBC News has learned that the UK has now agreed to be part of the $1.5bn (£1bn) project.

Those involved describe it as the most important experiment since the search for the Higgs boson.

"It is the next big thing in particle physics," said Prof Stefan Soldner-Rembold of the University of Manchester, who is working at Fermilab.

"It is as big as the search for the Higgs and will revolutionise our understanding of physics."

British component

The director of Fermilab, Nigel Lockyer, told BBC News that the plan to build the Long Baseline Neutrino Experiment (LBNE) was well under way and he was seeking international partners.

"We think that the experiment will cost $1.5bn to build and the US has committed to putting $1bn on the table. So it is a kind of 2/3rds to a 1/3rd arrangement, and so you shop around and see who wants to contribute what."

It has emerged that the UK has just signed up to the project. The Science and Technology Facilities Council (STFC) aims to contribute up to £20m to the project.

BBC News understands that nine British universities will be involved. These include Manchester, Cambridge, Oxford and University College London.

The head of STFC, John Womersley, described the development as a "win-win situation".

"The UK has shown its interest in the Fermilab initiative. What I hope is that other European participants will get involved. If it can go ahead, it will be an important step for the US and an important step for Europe for a global physics programme."

The UK's role will be to help to build a giant neutrino detector. The detector is likely to be about 12m (39ft) across.

Flavour flip

Neutrinos are ghostly particles that permeate the Universe. They hardly interact with our world, tending to pass right through the Earth.

But 16 years ago, Japanese researchers discovered that these ephemeral flecks did indeed have mass, and not only that - they changed from one form, or flavour, to another as they travelled.

neutrino particle

This solved a puzzling observation made by US researchers in a South Dakota mine decades earlier. They found that they were not detecting as many neutrinos coming from the Sun as they were expecting.

The Japanese result suggested that some of them had changed into another type of neutrino on their way to Earth.

This discovery cannot be explained by the current theory of sub-atomic physics. So some physicists believe that by finding out how these neutrinos change flavour and determining their exact mass will give a deeper understanding of how the Universe works and specifically how it came into being.

Matter trick

Current theories of creation suggest that shortly after the Big Bang, there were equal amounts of matter (from which our Universe is made) and anti-matter.

How the neutrino beam would be fired underground.

If that were the case, the two would have cancelled each other out - and yet here we are.

Some believe that contained within the neutrino's oscillation is the cosmic sleight-of-hand - called CP violation in the jargon - that enabled some matter to survive after the Big Bang.

"Neutrinos tell us something about the origins of the Universe," said Prof Soldner-Rembold. "We know there is more matter than anti-matter in the Universe, and that is why we are all here.

"But we don't really understand why, and neutrinos might provide a key to why there is more matter than anti-matter and ultimately why we are here."

It is more likely for neutrinos to change from one type to another if they pass through rock.

So, in order to maximise the chances of seeing this rare event, Fermilab plans to create a beam that will send trillions of neutrinos every second through 1,300km of rock from Illinois to a giant detector in South Dakota.

The beam itself will start 1.5km under the surface, and at its greatest depth will be some 30km down.

The construction of the project is expected to be completed in 10 years' time.

Such experiments do not come cheap, and Fermilab's plan is one of three big experiments that have been proposed to study neutrinos. The others are a European initiative led by Cern, and one suggested by the Japanese.

Realistically, only one of these experiments will be funded by the international community, and the three proposals have been involved in a very high-stakes game of poker to determine which experiment will get the nod.

Some argue that the European and Japanese experiments are better in their own way. But there is also an argument that the Americans deserve this one. Europe already has the Large Hadron Collider at Cern, and siting the neutrino lab in the US means it too would have a particle physics flagship.

So, having secured congressional backing for the LBNE project this year, it may be that the Americans now hold the strongest hand, especially with India, Italy and now the UK lining up behind Fermilab.

Britain's Science Minister David Willetts is in Chicago to attend the annual meeting of the American Association for the Advancement of Science. He told the BBC: "It is great that British scientists are involved with this big project investigating fundamental questions about the nature of matter. It will explore the frontiers of science."

How to delete your Google location history

2014-01-13T12:04:00.000-05:00

(Credit: Screenshot by Matt Elliott/CNET)

Google can track your location and show you on Google Maps and Google Earth where you have been recently, which you may find useful, interesting, or invasive. Here's how to see if you have location history turned on and how to disable it.

You can delete portions of your location history or all of it, as well as disable the feature from tracking you in the future.

To see if you have location history enabled, head to the Google Maps Location history page. Click the gear-icon button to access History settings. Here, you can choose to disable or enable the service.

Disabling location history, however, does not remove your past history. If you'd like to erase the locations Google has stored for the past 30 days, head back to the Location history page. The default time period shows location history for the current day, so you may not see any plots on the map.

(Credit: Screenshot by Matt Elliott/CNET)

Use the pull-down menu below the calendar on the left to show your history, up to 30 days. If you choose a time period in which Google has tracked your location, you'll see the points where you've been on the map. And below the calendar, you'll see options to delete your history from the time period you have chosen or to delete all history.

You can also delete a specific location from your history. Click on one of the red points on the map, then in the pop-up window click "Delete from history."

For iOS users who want to disable Google from using location services, follow this path: Settings > Privacy > Location Services, and turn the slider switch off for Google Maps. For Android users looking to prevent Google from using location service on their mobile device, this Google Support page has instructions.

China's Moon rover sends back first photos.

2013-12-15T17:57:00.000-05:00

New images show the probe viewed from the rover

The first robot to land on the Moon in nearly 40 years, China's Jade Rabbit rover, has begun sending back photos, with shots of its lunar lander.

Jade Rabbit rolled down a ramp lowered by the lander and on to the volcanic plain known as Sinus Iridum at 04:35 Beijing time on Saturday (20:35 GMT).

It moved to a spot a few metres away, its historic short journey recorded by the lander.

On Sunday evening the two machines began photographing each other.

A Chinese flag is clearly visible on the Jade Rabbit as it stands deployed on the Moon's surface.

Images of the rover taken from the lunar probe were released by the Beijing Aerospace Control Centre

Ma Xingrui, chief commander of China's lunar programme, declared the mission a "complete success".

The first soft landing on the Moon since 1976 is the latest step in China's ambitious space programme, says BBC science reporter Paul Rincon.

The lander will operate there for a year, while the rover is expected to work for some three months.

The Chang'e-3 mission landed some 12 days after being launched atop a Chinese-developed Long March 3B rocket from Xichang in the country's south.

The official Xinhua news service reported that the lander began its descent on Saturday just after 1300 GMT, touching down in Sinus Iridum (the Bay of Rainbows) 11 minutes later.

"I was lucky enough to see a prototype rover in Shanghai a few years ago - it's a wonderful technological achievement to have landed," Prof Andrew Coates, from UCL's Mullard Space Science Laboratory, told BBC News.

Chang'e-3 is the third unmanned rover mission to touch down on the lunar surface, and the first to go there in more than 40 years. The last was an 840kg (1,900lb) Soviet vehicle known as Lunokhod-2, which was kept warm by polonium-210.

But the six-wheeled Chinese vehicle carries a more sophisticated payload, including ground-penetrating radar which will gather measurements of the lunar soil and crust.

The 120kg (260lb) Jade Rabbit rover can reportedly climb slopes of up to 30 degrees and travel at 200m (660ft) per hour.

Its name - chosen in an online poll of 3.4 million voters - derives from an ancient Chinese myth about a rabbit living on the moon as the pet of the lunar goddess Chang'e.

The rover and lander are powered by solar panels but some sources suggest they also carry radioisotope heating units (RHUs), containing plutonium-238 to keep them warm during the cold lunar night.

According to Chinese space scientists, the mission is designed to test new technologies, gather scientific data and build intellectual expertise. It will also scout valuable mineral resources that could one day be mined.

"China's lunar programme is an important component of mankind's activities to explore [the] peaceful use of space," Sun Huixian, a space engineer with the Chinese lunar programme, told Xinhua.

After this, a mission to bring samples of lunar soil back to Earth is planned for 2017. And this may set the stage for further robotic missions, and - perhaps - a crewed lunar mission in the 2020s.

Dean Cheng, a senior research fellow at the Heritage Foundation, a conservative think-tank in Washington DC, said China's space programme was a good fit with China's concept of "comprehensive national power". This might be described as a measure of a state's all-round capabilities.

But he said that China did not see itself as being in a "space race" with anyone else. "I'm comparing it specifically to how the US and the Soviets were behaving in the late 1950s and 1960s when you had space launches almost every month.

"Look at how often the Chinese do manned missions - it's almost every other year."

Instead, the country is methodically and patiently building up the key elements needed for an advanced space programme - from launchers to manned missions in Earth orbit to unmanned planetary craft - and it is investing heavily.

Mr Cheng added: "China is saying: 'We are doing something that only two other countries have done before - the US and the Soviet Union."

The landing site of Sinus Iridum is a flat volcanic plain, part of a larger feature known as Mare Imbrium that forms the right eye of the "Man in the Moon".

Complete Launching Footage: Chang'e -3 'Jade Rabbit' Lunar Land:

Are we too dependent on technology?

2013-11-11T21:20:00.000-05:00

What would happen if your computer crashed? What about if you lost your cellphone? If just thinking about these scenarios gives you anxiety, you’re not alone. Most of us rely so much on technology these days that losing it, even for a day, would be extremely inconvenient, and for some, life-altering.
So what if you took that technology out of your life for a day voluntarily? What would your day look like if you couldn't chronicle every step on Facebook or Twitter?

Here are are seven signs that we depend too much on technology:

1. If the Internet is down, work is over for the day. I don’t know about you, but I’ve been at jobs where if the Internet isn’t working, then work comes to a standstill. How can you work if you can’t send an email, right? Seriously. I was sent home one day at my last job because the Internet was down. Sure, I stopped to chat with a co-worker on the way out. And during that conversation, we came up with a way to effectively tackle a work-related problem. But otherwise, work was over for the day.

2. Buyer’s remorse is much more common. How many times have you ordered a dress, or a pair of shoes, or a television online, only to realize when it arrives at your door that you need to send it back? Buying things online is wonderfully convenient when it’s an item that you absolutely want and are sure to keep. But when it’s not, it can be an all-consuming thing just to figure out how to get it back where it came from. We recently bought a bench online, only to realize after we spent three hours trying to put it together that it wouldn’t work for us. Returning it assembled wasn’t an option and neither was taking it apart since we had hammered some of the screws in place. What did we do? We finally sold the brand-new bench on Craigslist for half the retail price. Internet shopping fail.

3. You don’t live in the moment. Picture the scenario: You are trying desperately to video your third-grader’s solo in her ballet recital. You can’t get the camcorder to turn on. When it finally does finish booting up, it tells you to change the battery pack. You do. And then you realize your daughter’s dance solo is over. There are so many moments we try to capture on video, only to realize that we’re not experiencing the moment we are trying to capture.

Dr. Nicholas Bowman, assistant professor of Communication Studies at West Virginia University, sees it differently, though. “One might counter-argue that while we sometimes remove ourselves from ‘our moment’ by watching something through our smartphone screen compared to watching it with our eyes, networked technologies allow us to live in the moments of millions of people every day — such as following with eyewitness accounts the riots in Egypt, or the tsunami that struck Japan a few years ago or even the delicious burger I prepared on my patio last night,” Bowman tells MNN.

4. Nobody knows a phone number. It’s very possible that you have your husband’s number memorized. It’s also very possible that he’s listed by name on your phone and you haven’t the faintest idea what his number is. If you lost your cellphone and all of your contacts, it’s very possible you’d have no idea how to get in contact with anyone, let alone someone important to you. And you can’t even look it up since cellphone numbers are unlisted.

5. You are dreading having to break up with your boyfriend face-to-face. You’re considering doing it via text message. How many of us today have serious conversations over text message? I know someone who got fired through a text. It isn’t pretty. Text messaging is convenient, but when it comes to getting your message across clearly, a face-to-face conversation is not only best; it is necessary. I can’t tell you how many fights have been started in my house by misconstruing a text or an email, not to mention the amount of time spent poring over text messages analyzing their inflection and meaning. (“What did he mean by ‘I’m OK’ — ‘I’m OK’ or ‘I’m OK’???) All that aggravation could have been saved if someone had just picked up the phone.

6. Brick and mortar stores are going the way of the dinosaurs. I don’t remember the last time I bought a box of diapers or a pair of headphones in the store. That’s because these days, you can order almost anything and everything online. Definitely more convenient for me, but the phenomenon is causing retailers to close hundreds of brick-and-mortar stores across the country. In 2013, retailers such as Barnes & Noble, Best Buy, and Office Max closed hundreds of their retail stores. An eerie recent news story told of Sears’ decision to turn some of its retail stores into massive data centers — a fitting turn of events in this largely digital age.

7. Without your phone, you feel naked. Perhaps this is the crux of the issue. Technology addiction is a reality these days, with people checking their emails and text messages as much as 30 to 40 times an hour. I know people who jokingly refer to their Blackberrys as “Crackberrys” because checking them is so addictive. But technology addiction is no joke. Technology can be a good thing, but too much of it can leave you stressed and strung-out. Studies have shown that smartphone usage can lead to catastrophic events such as car accidents, and are a primary cause of poor work-life balance.

So I guess the choice remains in each person’s hands. The balance we need to find is in appreciating and using technology the right way, but still knowing when to turn it off to experience life to its fullest. Using technology as a tool is the key, Bowman says. “In school, children don't have to memorize as many facts as their grandparents did because they can Google it, but this also gives children the ability to move past simple memorization and into more advanced levels of analysis, problem-solving, and synthesis of old knowledge into new ideas,” he explains.

And when technology isn’t at your fingertips (such as when you lose your cellphone), try to experience and enjoy the moments you have instead of focusing on what you don’t.

Apple products in history

2013-10-14T20:13:00.001-04:00

We take a look at some of Apple disparity between how the products looked then, photographically, and how they look today.

The Apple Lisa 2 computer.

A prototype of the eMate computer.

The 1987 Macintosh SE.

An early Apple joystick.

A 1986 Apple mouse.

The 2002 iMac G4.

iPods in many colors.

The 2001 iMax G3 "Flower Power."

Macintosh PowerBook 170 LPGA Special Edition, 1992

The Newton MessagePad 120.

Power Macintosh G3, 1999

Quicktake 100 Camera

Quicktake_200, an early Apple digital camera.

Apple Lisa 2, 1984

The Apple II computer

US and UK 'crack online encryption'

2013-09-07T19:07:00.000-04:00

US and UK intelligence have reportedly cracked the encryption codes protecting the emails, banking and medical records of hundreds of millions of people.

Disclosures by leaker Edward Snowden allege the US National Security Agency (NSA) and the UK's GCHQ successfully decoded key online security protocols.

They suggest some internet companies provided the agencies backdoor access to their security systems.

The NSA is said to spend $250m (£160m) a year on the top-secret operation.

It is codenamed Bullrun, an American civil-war battle, according to the documents published by the Guardian in conjunction with the New York Times and ProPublica.

The British counterpart scheme run by GCHQ is called Edgehill, after the first major engagement of the English civil war, say the documents.

'Behind-the-scenes persuasion'

The reports say the UK and US intelligence agencies are focusing on the encryption used in 4G smartphones, email, online shopping and remote business communication networks.

The encryption techniques are used by internet services such as Google, Facebook and Yahoo.

Under Bullrun, it is said that the NSA has built powerful supercomputers to try to crack the technology that scrambles and encrypts personal information when internet users log on to access various services.

The NSA also collaborated with unnamed technology companies to build so-called back doors into their software - something that would give the government access to information before it is encrypted and sent over the internet, it is reported.

As well as supercomputers, methods used include "technical trickery, court orders and behind-the-scenes persuasion to undermine the major tools protecting the privacy of everyday communications", the New York Times reports.

The US reportedly began investing billions of dollars in the operation in 2000 after its initial efforts to install a "back door" in all encryption systems were thwarted.

'Gobsmacked'

During the next decade, it is said the NSA employed code-breaking computers and began collaborating with technology companies at home and abroad to build entry points into their products.

The documents provided to the Guardian by Mr Snowden do not specify which companies participated.

The NSA also hacked into computers to capture messages prior to encryption, and used broad influence to introduce weaknesses into encryption standards followed by software developers the world over, the New York Times reports.

When British analysts were first told of the extent of the scheme they were "gobsmacked", according to one memo among more than 50,000 documents shared by the Guardian.

NSA officials continue to defend the agency's actions, claiming it will put the US at considerable risk if messages from terrorists and spies cannot be deciphered.

But some experts argue that such efforts could actually undermine national security, noting that any back doors inserted into encryption programs can be exploited by those outside the government.

It is the latest in a series of intelligence leaks by Mr Snowden, a former NSA contractor, who began providing caches of sensitive government documents to media outlets three months ago.

In June, the 30-year-old fled his home in Hawaii, where he worked at a small NSA installation, to Hong Kong, and subsequently to Russia after making revelations about a secret US data-gathering programme.

A US federal court has since filed espionage charges against Mr Snowden and is seeking his extradition.

Mr Snowden, however, remains in Russia where he has been granted temporary asylum.

Mark Ward

Technology correspondent, BBC News

Encryption involves scrambling text to make it unreadable without the right key. Typically data encryption uses numbers hundreds of digits long as those keys. That renders data secure because it would take thousands of years to try all possible keys for a particular message.

The NSA and GCHQ have apparently managed to get around this several different ways. They have used supercomputers to crank through potential keys very quickly, exploited known weaknesses in widely used web and mobile security protocols to read messages, and forced tech firms to install backdoors in software.

In addition, the NSA is believed to have subverted a US federal program to create new encryption algorithms so it can more easily get at any messages or data they were supposed to protect.

Critics say the NSA/GCHQ approaches are short-sighted because any backdoor could equally be used by spies and crooks and undermines the role the web plays in modern life.

'Fastest man-made spinning object' made by scientists

2013-08-28T16:37:00.000-04:00

The red squiggles indicate the polarisation of the light beam, which changes as it goes through the purple sphere

A team of researchers claims to have created the world's fastest spinning man-made object.

They were able to levitate and spin a microscopic sphere at speeds of up to 600 million revolutions per minute.

This spin speed is half a million times faster than a domestic washing machine and more than a thousand times faster than a dental drill.

The work by the University of St Andrews scientists is published in Nature Communications.

Although there is much international research exploring what happens at the boundary between classical physics and quantum physics, most of this experimental work uses atoms or molecules.

Microscopic sphere

The St Andrews team aimed to understand what happened for larger objects containing a million million atoms or more.

To do this they manufactured a microscopic sphere of calcium carbonate only four millionths of a metre in diameter.

The team then used the miniscule forces of laser light to hold the sphere with the radiation pressure of light - rather like levitating a beach ball with a jet of water.

They exploited the property of polarisation of the laser light that changed as the light passed through the levitating sphere, exerting a small twist or torque.

Placing the sphere in vacuum largely removed the drag due to any gas environment, allowing the team to achieve the very high rotation rates.

In addition to the rotation, the team observed a "compression" of the excursions or "wobble" of the particle in all three dimensions, which can be understood as a "cooling" of the motion.

Essentially the particle behaved like the world's smallest gyroscope, stabilising its motion around the axis of rotation.

Dr Yoshihiko Arita of the university's School of Physics and Astronomy said: "This is an exciting, thought-provoking experiment that pushes the boundary of our understanding of rotating bodies.

Quantum friction
"I am intrigued with the prospect of extending this to multiple trapped particles and rotating systems.

"We may even be able to shed light on the area of quantum friction - that is does quantum mechanics put the brakes on the motion or spinning particle even though we are in a near perfect vacuum with no other apparent sources of friction?"

Dr Michael Mazilu, a newly appointed lecturer in the school, added: "This system poses fascinating questions with regard to thermodynamics and is a challenging system to model theoretically.

"The rotation rate is so fast that the angular acceleration at the sphere surface is one billion times that of gravity on the Earth surface. It's amazing that the centrifugal forces do not cause the sphere to disintegrate."

The third member of the team, Professor Kishan Dholakia, said he believed they had "performed a real breakthrough piece of work" that would resonate with the international community.

"In addition to the exciting fundamental physics aspects, this experiment will allow us to probe the nature of friction in very small systems, which has relevance to the next generation of microscopic devices. And it's always good to hold a 'world record' - even if for only a while," he added

Analysis

The aim of the experiment was to see what would happen if a microscopic sphere was spun as fast as was technically possible.

The team balanced it on a laser beam in a complete vacuum and then spun it using the light itself.

They saw it spin faster and faster until it reached 600 million rpm - and then it seemed to vanish!

The researchers don't know what happened to the sphere - but one possibility is that the object may have reached some theoretical speed limit - after which it changed in some way.

The next step for the researchers is to discover what became of the object and whether they really have discovered a completely new physical phenomenon.

Google launches Chromecast TV.

2013-07-29T18:52:00.000-04:00

The device plugs into a television's HDMI slot

Google has announced a low-cost competitor to Apple TV - a "dongle" device called Chromecast.

The dongle is plugged into a television's HDMI port, and allows users to stream media from smartphones, tablets and computers.

Launching immediately in the US, the device will cost $35 (£23). There is as yet no word on international launches.

Google also announced an upgraded Nexus 7 tablet, the first to run the new version of the Android system.

Failed attempts

Chromecast is Google's latest attempt to gain ground in the television industry.

In 2012, Google faltered in its attempts to make a move into the living room, considered by many experts to be ripe ground for making large profits through advertising.

Google's partnership with Sony, with which it released a £200 set-top box, was poorly received.

That attempt followed an even earlier false start in 2010 when it launched Google TV, a service that was blocked by several TV networks, and suffered greatly from requiring consumers to buy expensive hardware.

More recently, the orb-shaped Nexus Q device, announced last year, fell flat almost immediately - Google pulled it from sale in response to "feedback".

With Chromecast, Google is attempting to simplify its large-screen offering, focusing on streaming clips from services such as YouTube and Netflix via a far cheaper device.

The dongle plugs into a television's HDMI port, and uses wireless home internet to link to devices.

However, unlike other similar devices, such as Apple TV, the media is streamed from the cloud, rather than from the mobile device itself.

This, Google said, allowed for higher-quality streaming, and had less impact on battery life.

The search giant was especially keen to stress the dongle's ability to stream across multiple operating systems, be it Android or Apple's iOS.

This aspect in particular is central to Google's core strategy, said Gartner analyst Carolina Milanesi.

"It's a big departure from the Nexus Q," she told the BBC. "What it boils down to is a focus around YouTube - and getting people back into that ecosystem.

"If you look at the opportunities around advertising, they're getting eyeballs back to that."

New Nexus

Also shown off at the event was Google's updated Nexus 7 tablet, which will go on sale in the "coming weeks".

Nexus 7

The tablet will be the first to run Android 4.3, the latest iteration of the Jelly Bean flavour of Google's mobile operating system.

Among the software's new features will be the ability to set restricted profiles, meaning parents can, for example, only give their child access to certain functions on a device.

The Asus-built device is slightly smaller, and 50g (1.8oz) lighter, than the original Nexus 7, which was launched last year.

The new device will have a screen resolution higher than any in its class, boasting 323 pixels per inch.

That is significantly higher than the iPad Mini's 163ppi and the 7in Kindle Fire HD's 216ppi.

But Jason Jenkins, from technology website Cnet, said it still had a lot of ground to make up with consumers.

"I am not convinced that ordinary consumers will respond better to this tablet than the last one," he said.

"Apple has established such momentum, Google's real challenge isn't just making a better tablet than Apple, it's persuading ordinary people to care that it makes one at all."

The new Nexus 7 will cost $30 more than it predecessor at $229 (£150), with other international prices yet to be announced.

The price point keeps it in line with Amazon's Kindle Fire, another key competitor - and considerably cheaper than Apple's iPad Mini, which retails starting at $329, or £269 in the UK.

Data storage Byte-sized Infographic guide.

2013-06-22T18:09:00.000-04:00

Information is everywhere – whether it’s digital information in our devices, analogue content in books, or biological data encoded in our cells. But how do they compare in terms of storage amount? How have our means of storing information grown over the decades? And do you know what a zettabyte or a yottabyte is?

Here are to help with our infographic guide to data storage.

The Wimshurst machine.

2013-06-17T13:02:00.001-04:00

Wimshurst machine with two Leyden jars.

The Wimshurst influence machine is an electrostatic device for generating high voltages developed between 1880 and 1883 by British inventor James Wimshurst (1832 – 1903).

It has a distinctive appearance with two large contra-rotating discs mounted in a vertical plane, two cross bars with metallic brushes, and a spark gap formed by two metal spheres.

Description

These machines belong to a class of generators called influence machines, which separate electric charges through electrostatic induction, or influence. Earlier machines in this class were developed by Wilhelm Holtz (1865 and 1867), August Toepler (1865), and J. Robert Voss (1880). The older machines were less efficient and exhibited an unpredictable tendency to switch their polarity. The Wimshurst did not have this defect.

In a Wimshurst machine, the two insulated discs and their metal sectors rotate in opposite directions passing the crossed metal neutralizer bars and their brushes. An imbalance of charges is induced, amplified, and collected by two pairs of metal combs with points placed near the surfaces of each disk. These collectors are mounted on insulating supports and connected to the output terminals. The positive feedback increases the accumulating charges exponentially until the dielectric breakdown voltage of the air is reached and a spark jumps across the gap.

The machine is theoretically not self-starting, meaning that if none of the sectors on the discs has any electrical charge there is nothing to induce charges on other sectors. In practice, even a small residual charge on any sector is enough to start the process going once the discs start to rotate. The machine will only work satisfactorily in a dry atmosphere. It does require mechanical power to turn the disks against the electric field, and it is this energy that the machine converts into electric power. The output of the Wimshurst machine is essentially a constant current that is proportional to the area covered by the metal sectors and to the rotation speed. The insulation and the size of the machine determine the maximum output voltage that can be reached. The accumulated spark energy can be increased by adding a pair of Leyden jars, an early type of capacitor suitable for high voltages, with the jars’ inner plates independently connected to each of the output terminals and the jars’ outer plates interconnected. A typical Wimshurst machine can produce sparks that are about a third of the disc's diameter in length and several tens of microamperes.

Operation

Suppose that the conditions are as in the figure that is the segment A1 is positive and the segment B1 negative. Now, as A1 moves to the left and B1 to the right, their potentials will rise on account of the work done in separating them against attraction. When A1 comes opposite the segment B2 of the B plate, which is now in contact with the brush Y, it will be at a high positive potential, and will therefore cause a displacement of electricity along the conductor between Y and Y1 bringing a large negative charge on B1 and sending a positive charge to the segment touching. As A1 moves on, it passes near the brush Z and is partially discharged into the external circuit. It then passes on until, on touching the brush X it is put in connection with X, and has a new charge, this time negative, driven into it by induction from B2. Positive electricity, then, being carried by the conducting patches from right to left on the upper half of the A plate, and negative from left to right on its lower half.

The two contra-rotating insulating discs (usually made of glass) have a number of metal sectors stuck onto them. The machine is provided with 4 small earthed brushes (2 on each side of the machine on shafts at 90 degrees to each other), plus a pair of charge collection combs.

Assume that a single sector on one glass plate has a positive electrostatic charge. As the sector passes a sector on the other plate, the positively charged sector attracts the electrons in the neighbouring sector to the surface next to the positive sector. This process repeats as the discs revolve until one of the sectors on the other disc passes one of the earthed brushes. This brush discharges the positive charge on the opposite side of the sector to where the electrons have migrated. As the sectors part, this second sector now retains a net negative charge. This negative charge will now repel electrons on sectors on the other disc as they pass. Once again earthed brushes dissipate the negative charge on the outside of those sectors leaving a net positive charge. The repeated induction of charges is cumulative and if it were not for the current drawn would continue until the insulation broke down. The positive and negative charges are collected by combs to charge the Leyden jars. It is the mechanical energy required to separate the opposing charges on the adjacent sectors that provides the energy source for the electrical output.

New blood pressure sensor device gives better measurement.

2013-06-10T19:07:00.000-04:00

Device monitors fluctuations in blood pressure

A new device could improve how blood pressure is measured, according to NHS researchers.

A team at University College London showed a sensor worn on the wrist could measure the pressure of blood leaving the heart throughout the day.

Normally blood pressure is measured in the arteries in the arm, but the pressure at the heart might be a better predictor of future health problems.

If blood pressure is too high it can lead to heart attacks and stroke.

About a third of people in the UK have hypertension, dangerously high blood pressure, but most are unaware of the condition.

A team at the NHS National Institute of Health Research (NIHR) trialled the sensor, which contains a mini-plunger that moves up and down as blood pulses past with every heartbeat.

A computer programme in the wrist strap used this "pulse wave" to work out the pressure in the heart. This was compared with measures taken from sensors in patients' hearts.

"It was remarkably accurate," said Prof Bryan Williams, the director of the NIHR University College London Hospitals Biomedical Research Centre.

Disease predictor

Guidelines in the UK recommend that blood pressure is measured at home over the course of 24 hours before drugs for hypertension are prescribed.

Their study, published in the journal Hypertension, showed that the measurements in the arm did not reflect the true changes in blood pressure at night.

Prof Williams said: "What we have shown is that pressures by the heart do not dip as much during sleep as we previously thought.

"We know the pressure when someone is asleep is a strong predictor of heart disease. This [the device] almost certainly gives a better measure than blood pressure in the arm.

"This is not mainstream, but in the future you could see people having their central blood pressure measured instead of in the arm."

Clinical trials will now test whether using the device leads to better diagnoses.

Amy Thompson, senior cardiac nurse at the British Heart Foundation, said: "It's still early stages for this new measuring device, but advances in technology could lead to better prevention and treatment of high blood pressure in the future.

"The only way to know if your blood pressure is high is to have it measured. The easiest way to do this is by visiting your GP surgery.

"However, blood pressure fluctuates throughout the day depending on what you're doing, and if it's found to be high you may need to have it tested several times."

Tech Tools to Stop Phone Tapping.

2013-06-07T21:33:00.000-04:00

Photo: TORFone

Threats of Big Brother watching U.S. citizens seem to have gained credence for several reasons this week. It began when British newspaper The Guardian broke a story revealing that the U.S. government has been secretly, although lawfully,
collecting the phone records of millions of Verizon customers for years, specifically business landline users. (The data was limited to call logs, including numbers called, but not the content of conversations.)

"This program has been lawful. It’s been approved," Senate Intelligence Committee Chairman Dianne Feinstein said in a television interview. The data collected can only be used when there is a suspicion that an individual is involved with terrorist activities, she said.

While the court order was approved in the usual legal way, some people may be uncomfortable with the notion of government snooping. And while the alleged court order only covers monitoring Verizon business landlines, the document's language is broad enough to include cellphones.

You have a number of options if you want to increase your privacy when making a call. Some are simple; others are more complicated.

Anonymous phones

A payphone may seem like a safe solution. After all, the bad guys always used them in old movies, and there are still 305,000 working pay phones in the United States, according to the American Public Communications Council. However, because a payphone uses a landline and never moves, calls can be easily traced. Still skeptical? Reddit user Detached09 wrote, "If you don't think a payphone is traceable: Pick one up, dial 9-1-1, scream, and hang up. Wait and see how long it takes the cops to show up."

Instead, buy a disposable phone with a pre-programmed number from any convenience store or other outlet, pay cash and make calls. Using this method, you avoid associating your personal information with a cellphone carrier account. (Although the more calls you make, the easier it is to deduce your identity based on the people you call.)

Encryption

You can also use an encryption app to make calls from your regular smartphone. RedPhone is available for free on Android, for example. Once you install it on a phone, you can make free voice-over-IP calls through the app to other RedPhone users. Similarly, iPhone and Android owners can use Silent Phone from Silent Circle. The app is free, but you must become a member of Silent Phone to use the service, which runs $20 a month. However, these apps only encrypt the conversation of the call. They don't hide information about whose devices are on the call.

Anonymizing service

Alternatively, instead of using your cellphone to make a call, use a computer — preferably a public one, like those at most libraries. That way, your home computer's IP address won't be identified with the call. Or, if you use a device at home, go through an anonymizing service. TORFone is an Internet calling-app that routes your call through six anonymizing servers and encrypts your conversations, hiding both whom you're talking with and what you're saying.

No method is failsafe. And in some countries outside the United States, encryption apps are illegal. If you're traveling, check with the U.S. State Department on communication rules specific to your destination.

Police can still find your deleted message.

2013-05-22T19:45:00.000-04:00

A forensics tool from Cellebrite can crack a phone's password and retrieve all of its data.

Think that a secure password and erasing your phone's memory will protect sensitive information on your smartphone? Think again.

Smartphone forensics experts can retrieve just about anything from any phone. Police will often seize and analyze phones for evidence of things such as indecent photos and videos, what calls were placed when and to whom, browser history, calendar events and explanations of a suicide or murder.

All of that can be uncovered whether or not a user deleted it from their phone.
"It makes it much, much harder, but wiping a phone doesn't always mean you can't get the data," said Courtney Lancaster, forensic analyst with IT consulting company TCS, at the CTIA wireless industry trade show in Las Vegas.
Forensic analysts have dozens of tools that allow them to access many layers of data on a device.

A so-called "physical" analysis can typically retrieve deleted information that is hidden deep within a smartphone's memory. When a photo is saved, for example, the device's operating system will typically store variations of that image in several different locations -- a thumbnail view may still be available even if the original isn't.

Media can be recovered with a physical analysis even if they have been delivered by Snapchat, a controversial app that sends photos or videos to a device for just seconds. (Snapchat messages are designed to vanish seconds after they're opened, but a security probe revealed that some videos are being stored on recipients' iPhones.)

It takes a long time, Lancaster says, but scouring a smartphone's file system bit by bit is usually worth the effort.
Realizing their smartphones could potentially serve as smoking guns in court, criminals will often attempt to destroy their phones. That can make a forensics expert's job more difficult -- but not impossible. Memory chips can often be retrieved and analyzed.

"Physical damage is not always the deal-breaker that it used to be," said Lancaster. "Data is stored where data is stored, so we don't care so much about the outer casing. Even water is not always a problem."

Those are extreme circumstances, however. Usually, retrieving information from smartphones is a cinch.
With tools like Cellebrite's forensic computer, law enforcement can simply plug in a phone and download the device's memory to a flash drive in a matter of seconds. Passwords make the job take a bit longer, but forensic computers can crack codes or bypass them relatively quickly.

It's not just law enforcement that uses Cellebrite: Best Buy (BBY, Fortune 500) relies on the tools to transfer data from customers' old phones to new ones. There are also dozens of Cellebrite devices available on eBay (EBAY, Fortune 500), many of which are selling for less than $1,000. When new, Cellebrite tools can cost upwards of $10,000.

YouTube rolling pay-to-watch channels.

2013-05-09T16:51:00.003-04:00

YouTube says it has about one billion unique users to its service each month

YouTube has launched a trial scheme for paid channels on its website.

Under the pilot programme, a small number of content makers will offer the channels for subscriptions starting at $0.99 (£0.64) a month.

Each channel will offer a free 14-day trial and many will have discounted annual rates.

Although the initial 53-channel line-up is fairly niche, one expert suggested the move might ultimately squeeze some smaller rivals out of the market.

YouTube, which is owned by Google, said the launch was part of an effort to enable "content creators to earn revenue for their creativity".

For example, the children's television favourite, Sesame Street will offer full episodes on its pay channel when it launches.

Subscribers can pay using either their credit cards or through Google's own Wallet service.

The paid channels involved in the pilot are diverse.

They include National Geographic Kids, Acorn - which provides episodes from several British TV series -and Fix My Hog Premium, which is aimed at Harley Davidson motorcycle enthusiasts.

"This is just the beginning", YouTube said on its blog.

"We'll be rolling paid channels out more broadly in the coming weeks as a self-service feature for qualifying partners.

"And as new channels appear, we'll be making sure you can discover them."

Traditional TV turn-off?

The advent of paid channels on YouTube means Google joins Netflix, Hulu and Amazon in offering subscription-based alternatives to traditional pay-TV.

"The wider picture here is that the internet and TV worlds are colliding," Ian Maude, an online media expert at consultants Enders Analysis told the BBC.

"The YouTube move will make it much harder for smaller standalone online subscription-based platforms because Google has the infrastructure to make it easy for content to be hosted, delivered and billed for.

"But it was always inevitable that Google was going to do this."

One billion viewers

Google bought YouTube in 2006 for $1.65bn. The service is believed to generate a small amount of revenue from advertising, but the vast majority of its content has been free-to-watch.

To make itself more attractive to potential advertisers, YouTube has gradually added professional content, such as full-length films and TV shows, to its vast library of amateur videos.

YouTube says a billion people around the world use the service every month.

"If YouTube were a country, we'd be the third largest in the world after China and India," the company said in March.

Erase your data from an old computer or phone.

2013-04-29T14:41:00.000-04:00

If you're disposing of old documents such as bank statements and tax forms, security experts recommend shredding the paperwork so it can't be used by  identity theft.

It's a practice everyone should be familiar with, since it may be the top recommendation for preventing identity theft.

However, many consumers and organizations are turning to a paperless world, and records once held in filing cabinets are now stored on computer hard drives.

But computers eventually get replaced, and old computers are donated, recycled, handed down or refurbished — often with  personally identifiable information (PII) still on the machine.

Pick up any old computer being tossed out on the street, and odds are its hard drive will have a wealth of information on its previous owners.[7 Easy Ways to Get Your Identity Stolen]

The basics
Simply deleting the data by emptying the "trash" folder won't totally wipe all that information away.

Before you dispose of an old personal computer, the experts recommend that the very least you do is reformat your hard drive and reinstall the  operating system.. A better bet is to wipe your hard drive clean.

"With computers, it isn't difficult to wipe data, if you understand what you are doing and do it correctly," said Greg Kelley, chief technology officer with Vestige Digital Investigations in Medina, Ohio.

"The most important thing to consider is that to be certain that you got all of your data, you need to wipe the entire hard drive," Kelley said. "Programs such as BCWipe and Eraser can perform this work."

An even easier way to do this, provided the user has Windows Vista or better, is to create a system repair disk and then format the hard drive using the standard format command, said Matthew Kinney, executive vice president of research and development with staffing-software maker BWSI in Phoenix.

"This also uses the write-zero approach, overwriting each block with binary zeroes, and is super easy," Kinney said. "I have recommended this to many of my friends who aren't tech people and have them use the instructions on About.com."

However, not every attempt to  clean off the hard drive is 100 percent successful. If that's the case, and if you want to keep the hard drive with the computer, Kelley recommended taking the machine to a qualified computer technician to perform the work.

"Make sure that the computer technician is one [who] understands that deleting a file, formatting a hard drive or reinstalling an operating system doesn't render the data unrecoverable," Kelley said. "Those technicians will know enough to identify the proper tools to wipe your drive."

If you're sending your computer to be recycled, or you're donating it to a relative or a charity, the best way to protect your personal data is to simply remove the hard drive and physically destroy the drive.

Off the premises
Eliminating personal data from personal computers kept at home is relatively easy. The real problems lie with mobile devices and work computers.

Smartphone and tablet owners now store a great deal of personally identifiable information on these devices.

Apps are available to  "wipe" the devices if they are lost or stolen, but the technology is still relatively new and these apps leave some data behind.

"Many cellphones have a 'restore to factory defaults' option that will delete data, but in many instances, it has been shown that this does not always work," said Adam Wosotowsky, messaging data architect at Santa Clara, Calif., digital-security firm McAfee. "Additionally, they are not overwriting the data multiple times to prevent forensic equipment from being able to recover it."

If you intend to never use the phone again, the best option is to physically destroy it. However, if you want to recycle the phone, your safest option may be to sell it to a company that refurbishes phones for re-sale.

The reason to follow this path, said Kyle Marks of Retire-IT, a Columbus, Ohio, firm specializing in computer disposal, is because these companies could end up being liable if your personal data is found on a device they refurbished and sold. In this case, it is in their best interest to make sure your data is safe.

Do you trust your boss?
Businesses also have an interest in making sure personal data is kept secure. But Marks pointed out that while most companies have a strict record of incoming inventory, they are more lax when it comes to disposal of equipment.

If your computer is being replaced, or if you are leaving the company, you will want to make sure that you have at least deleted everything that holds your personally identifiable information, including temporary files and  browsing histories..

You can also ask your IT support staff about what happens to old equipment, and whether the machines are wiped clean or the hard drives are reformatted.

"A mature, well-run company should have a formal procedure in place for computer disposal," Marks said. "But you have every right to be concerned if your IT support takes a 'we'll take care of it, don't worry' attitude when you ask about computer disposal."

Unfortunately, there might be nothing you can do about that.

"Once that data is on the computer, depending on company policy and local laws, you may no longer have ownership to that data," Kelley said.

Instead, Kelley said, leave your banking, personal emailing and social networking to your home computer. That way, you can control what happens to your personally identifiable information when the time comes to get rid of your old equipment.

New Earth-like planet found.

2013-04-19T17:38:00.001-04:00

This artist's concept depicts Kepler-62f, a planet 1.4 times the size of Earth that circles in the habitable zone of its host star.

NASA's Kepler space telescope has discovered three exoplanets that may be capable of supporting life, and one of them is perhaps the most Earth-like alien world spotted to date, scientists announced (April 18/13).

That most intriguing one is called Kepler-62f, a rocky world just 1.4 times bigger than Earth that circles a star smaller and dimmer than the sun. Kepler-62f's newfound neighbor, Kepler-62e, is just 1.6 times larger than Earth, making the pair among the smallest exoplanets yet found in their star's habitable zone — the just-right range of distances where liquid water can exist on a world's surface.

Kepler-62e and f, which are part of a newly discovered five-planet system, "look very good as possibilities for looking for life," said Kepler science principal investigator Bill Borucki, of NASA's Ames Research Center in Moffett Field, Calif. [9 Exoplanets That Could Host Alien Life]

The third potentially habitable planet, called Kepler-69c, is 1.7 times bigger than Earth and orbits a star similar to our own. It's the smallest world ever found in the habitable zone of a sunlike star, researchers said, and represents a big step toward discovering the first-ever "alien Earth"

"We're moving very rapidly toward finding an Earth analogue around a star like the sun," Borucki told SPACE.com.

Researchers announced these newfound planets — all three of which are "super-Earths," or worlds slightly larger than our own — today at a NASA news conference. The Kepler-62 discovery paper, led by Borucki, was also published today in the journal Science.

The three potentially habitable worlds are part of a larger haul. All told, the scientists rolled out seven new exoplanets today — five in the Kepler-62 system and two in Kepler-69.

Alien water worlds?

The five newfound planets in the Kepler-62 system, which is located about 1,200 light-years away in the constellation Lyra, range from 0.54 to 1.95 times the size of Earth. Only Kepler-62e and f are potentially habitable; the other three zip around the star at close range, making them too hot to support life as we know it, researchers said.

Kepler-62e and f take 122 and 267 days, respectively, to complete one orbit around their star, which is just 20 percent as bright as the sun. While nobody knows what the two exoplanets look like, a separate modeling study suggests they're both probably water worlds covered by endless, uninterrupted global oceans. [Two Habitable Alien Water Worlds? (Video)]

"There may be life there, but could it be technology-based like ours? Life on these worlds would be under water with no easy access to metals, to electricity, or fire for metallurgy," lead author Lisa Kaltenegger, of the Max Planck Institute for Astronomy and the Harvard-Smithsonian Center for Astrophysics, said in a statement.

"Nonetheless, these worlds will still be beautiful blue planets circling an orange star — and maybe life’s inventiveness to get to a technology stage will surprise us," she added.

Not surprisingly, Kepler-62e should be warmer than its more distantly orbiting neighbor. In fact, Kepler-62f may require a greenhouse effect to keep its ocean from freezing over, researchers said.

“Kepler-62e probably has a very cloudy sky and is warm and humid all the way to the polar regions," co-author Dimitar Sasselov of Harvard said in a statement. "Kepler-62f would be cooler, but still potentially life-friendly."

The new modeling study has been accepted for publication in The Astrophysical Journal.

Searching for Earth's twin

The $600 million Kepler observatory launched in March 2009 to hunt for Earth-size exoplanets in the habitable zone of their parent stars. Kepler finds alien worlds by detecting the tiny brightness dips caused when they transit, or cross the face of, their stars from the instrument's perspective.

Kepler has used this technique to great effect, spotting more than 2,700 potential planets since its March 2009 launch. While just 120 or so of these candidates have been confirmed to date, mission scientists estimate that more than 90 percent will end up being the real deal.

While Kepler has yet to discover a true Earth twin, it's getting closer and closer, Borucki said, pointing to the confirmation of Kepler-69c as an example. (That planet lies 2,700 light-years away, in the constellation Cygnus. Kepler-69c's neighbor Kepler-69b, which is about twice the size of Earth and too hot to host life, was also announced today.)

"I think we're making excellent progress in that direction," Borucki said. "We have a number of candidates that look good." Such steady progress makes sense, since Kepler will of course spot more transits the longer it looks. The telescope needs to observe three transits to flag a planet candidate, so detecting a potentially habitable world in a relatively distant orbit can take several years.

Kepler cannot search for signs of life on worlds like Kepler-62e, Kepler-62f and Kepler-69c, but the telescope is paving the way for future missions that should do just that, Borucki said.

"This is one of the early steps, but there's no mistake — we are on our way to explore the galaxy, to learn about life in the galaxy," he said.

Bitcoin: The world's first digital currency.

2013-04-12T18:55:00.000-04:00

The world’s “first decentralised digital currency” promises financial salvation, but what is it and can it really deliver?

Dubai. Greece. Spain. Portugal. Italy. Cyprus. Ireland. The list of countries needing financial bailouts seems to go on and on. And that’s before you include those banks in the US, the UK and beyond that were “too big to fail”.

As well as revealing the fragility of the global economy, the current crisis has also raised some existential questions about the nature of money.

Can any government really promise to protect the value of its currency and be taken at its word? And how – other than by hiding gold bars under their mattresses – can the residents of a country in crisis hope to safeguard their wealth? As a controversial economist once noted, there are times when all that seemed solid can melt into air.

One recent and much-publicised answer to this last question is a form of money that comes pre-dissolved into the ether: Bitcoins. The world’s “first decentralised digital currency” hit the headlines this week, but has been lurking at the edges of global attention for considerably longer.

Trust in maths

Born at the start of 2009 in the aftermath of the global financial crisis – courtesy of a mysterious and possibly non-existent Japanese programmer calling himself Satoshi Nakamoto – Bitcoins are a mathematical concoction, combining the attributes of a scarce commodity, like gold, with the frictionless trading of an electronic currency. They achieve this through the ingenious combination of three factors: “mining”, peer-to-peer networking and cryptography.

The first of these is one of the central reasons for their appeal. Despite being wholly electronic, every Bitcoin in existence has been “mined” by someone running Nakamoto’s software, which regulates the global supply of Bitcoins by forcing computers to crunch increasingly difficult equations in order to generate each coin. Coins emerge at a pre-determined rate: as more people use the software, it gets harder and harder to create them, with the global supply decelerating geometrically towards a predetermined limit. At the time of writing, there were a total of 11,023,350 Bitcoins in the world (one of the joys of an open digital currency is the ease of accessing statistics), and there will never be more than 21 million.

Like everything else about Bitcoins, these factors are hard-coded into its software – and it’s the peer-to-peer element of this software that makes the system so compelling. Almost every modern currency is guaranteed by the “fiat” of government regulation or laws. That is, their worth is based on faith in a central authority – and is undermined when faith declines in that authority.

Bitcoins have no central authority and no such promise, and rely on no intermediaries or banks to hold or to transfer money. Instead, each user operates an “electronic wallet” that embodies their money in a highly secure electronic form, and allows them to exchange Bitcoins directly with any other user on the network. Every transaction is automatically confirmed by the software of every other user, and cannot take place if it fails to match the network’s standards: each transaction is “stamped” with the unique time of its occurrence to prevent double spending, while the cryptographic standards in place ensure the network confirms the validity of every action taking place.

There is, in other words, no need ever to trust any central database or authority. It’s a narrative perfectly matched to troubled economic times, and one reason for the staggering increase in the recent value of Bitcoins. Buying a single Bitcon on 9 April 2013 – through any one of the growing number of online exchanges – would have cost you almost $200, more than fifteen times its $9 value in January. As author Paul Ford wrote in Businessweek: “There’s nothing to trust but math... [and] that’s where Bitcoin thrives: where people would prefer to throw in their lot with anonymous strangers instead of the world economy.”

Boom and bust

The recent surge of media-driven interest in Bitcoin has, however, shown every sign of becoming a speculative bubble. Come 10 April, the exchange value of Bitcoins plummeted by 60% from a brief high of $265 to around $150. These are numbers that belong more to a volatile commodity than to a currency, and that emphasise an uncomfortable paradox noted by Reuters finance blogger Felix Salmon at the start of April: “The commodity value of bitcoins is rooted in their currency value, but the more of a commodity they become, the less useful they are as a currency.”

As a currency, then, failure is already in the air. Yet this does not mean that the Bitcoin effect can be ignored, not least because it can be divided into two halves. On the one hand, there’s the computerised mining of a commodity strictly limited to a certain number of units. On the other hand, there is a genuinely trans-national medium for payment that is free of almost all the friction of a traditional financial system – and that brings with it a promise of security more transparent and verifiable than any bank or government can match.

Bitcoin’s software is entirely open source, and this means that its security algorithms have been subjected to just about the most rigorous testing and attempted cracking the world’s geeks can come up with. The consensus is: they’re extremely secure. Moreover, should the cryptography at some future point be found wanting, its flaws will almost certainly be identified and updated far faster than with any private system (a major software issue in March was resolved within six hours).

Interestingly, your Bitcoin wealth becomes most vulnerable the moment “real” currency gets involved. The central software may be secure, but online exchanges have been hacked – or closed up shop completely – at an alarming rate. Similarly, users’ computers can themselves be unsafe places to leave open digital wallets containing hundreds of thousands of dollars worth of virtual assets.

What’s needed is a way of taking advantage of the system’s astonishing openness and transactional security while evading its incentives towards illegality: something that opportunistic start-ups like OpenCoin are trying to tap into, under the tagline “committed to a simple, global and open currency system”.

It may sound outrageously ambitious, but it isn’t the first time we’ve seen the birth of a new monetary concept. During the Industrial Revolution, banks eager to fund booming trade and industry began issuing their own private currencies, a system whose booms and busts led to many of the centralised regulations we enjoy (or not) today.

Some economists, certainly, would welcome further disruption. Writing in 1976, Fredrich Hayek argued in The Denationalization of Money for the removal of the legal obstacles preventing people from using any kind of money they wanted, thus creating a kind of global battle between different rival systems.

“We have always had bad money,” Hayek argued “because private enterprise was not permitted to give us a better one.” No government has yet has acted on Hayek’s faith in the power of the open market. The world, though, may already have embarked on just such an experiment. Betting against Bitcoins is one thing. But the change they represent packs quite a punch – and, with conventional finance on the ropes, it’s still anybody’s fight.

The Knockout mouse.

2013-04-05T15:07:00.000-04:00

A laboratory mouse in which a gene affecting hair growth has been knocked out (left), is shown next to a normal lab mouse.

A knockout mouse is a genetically engineered mouse in which one or more genes have been turned off through a targeted mutation.
Knockout mice are important animal models for studying the role of genes which have been sequenced but whose functions have not been determined. By causing a specific gene to be inactive in the mouse, and observing any differences from normal behaviour or condition, researchers can infer its probable function.

Mice are currently the most closely related laboratory animal species to humans for which the knockout technique can easily be applied. They are widely used in knockout experiments, especially those investigating genetic questions that relate to human physiology. Gene knockout in rats is much harder and has only been possible since 2003.

The first knockout mouse was created by Mario R. Capecchi, Martin Evans and Oliver Smithies in 1989, for which they were awarded the Nobel Prize for Medicine in 2007. Aspects of the technology for generating knockout mice, and the mice themselves have been patented in many countries by private companies.

Use

Knocking out the activity of a gene provides information about what that gene normally does. Humans share many genes with mice. Consequently, observing the characteristics of knockout mice gives researchers information that can be used to better understand how a similar gene may cause or contribute to disease in humans.

Examples of research in which knockout mice have been useful include studying and modeling different kinds of cancer, obesity, heart disease, diabetes, arthritis, substance abuse, anxiety, aging and Parkinson's disease. Knockout mice also offer a biological and scientific context in which drugs and other therapies can be developed and tested.

Millions of knockout mice are used in experiments each year.

Strains

A knockout mouse (left) that is a model of obesity, compared with a normal mouse.

There are several thousand different strains of knockout mice. Many mouse models are named after the gene that has been inactivated. For example, the p53 knockout mouse is named after the p53 gene which codes for a protein that normally suppresses the growth of tumours by arresting cell division. Humans born with mutations that deactivate the p53 gene suffer from Li-Fraumeni syndrome, a condition that dramatically increases the risk of developing bone cancers, breast cancer and blood cancers at an early age. Other mouse models are named, often with creative flair, according to their physical characteristics or behaviours.

Procedure

The procedure for making mixed-gentotype blastocyst.

There are several variations to the procedure of producing knockout mice; the following is a typical example.

The gene to be knocked out is isolated from a mouse gene library. Then a new DNA sequence is engineered which is very similar to the original gene and its immediate neighbour sequence, except that it is changed sufficiently to make it inoperable. Usually, the new sequence is also given a marker gene, a gene that normal mice don't have and that confers resistance to a certain toxic agent or that produces an observable change (e.g. colour or fluorescence). The chances of a successful recombination event are relatively low, so the majority of altered cells will have the gene changed for only one of the two relevant chromosomes - they are said to be heterozygous.
From a mouse blastocyst (a very young embryo consisting of a ball of undifferentiated cells with surrounding extra-embryonic cells), stem cells are isolated; these can be grown in vitro. For this example, we will take a stem cell from a white mouse.
The stem cells from step 2 are combined with the new sequence from step 1. This is done via electroporation (using electricity to transfer the DNA across the cell membrane). Some of the electroporated stem cells will incorporate the new sequence into their chromosomes in place of the old gene; this is called homologous recombination. The reason for this process is that the new and the old sequences are very similar. Using the marker gene from step 1, those stem cells that actually did incorporate the new sequence can be quickly isolated from those that did not.
The stem cells from step 3 are inserted into a mouse blastocyst. For this example, we use blastocysts from a grey mouse. These blastocysts are then implanted into the uterus of female mice, to complete the pregnancy. The blastocysts contain two types of stem cells: the original ones (grey mouse), and the newly engineered ones (white mouse). The newborn mice will therefore be chimeras: parts of their bodies result from the original stem cells, other parts result from the engineered stem cells. Their furs will show patches of white and grey.
Newborn mice are only useful if the newly engineered sequence was incorporated into the germ cells (egg or sperm cells). These new mice are crossed with others of the white type for offspring that are all white. These mice still contain one functional copy of the gene and must be further inbred to produce mice that carry no functional copy of the original gene (i.e. are homozygous for that allele).

A detailed explanation of how knockout (KO) mice are created is located at the website of the Nobel Prize in Physiology or Medicine 2007.

Limitations

Breeding scheme for producing knockout mice. Blastocysts containing cells, that are both wildtype and knockout cells, are injected into the uterus of a foster mother. This produces offspring that are either wildtype and coloured the same colour as the blastocyst donor (grey) or chimera (mixed) and partially knocked out. The chimera mice are crossed with a normal wildtype mouse (grey). This produces offspring that are either white and heterozygous for the knocked out gene or grey and wildtype. White heterozygous mice can subsequently be crossed to produce mice that are homozygous for the knocked out gene.

The National Institutes of Health discusses some important limitations of this technique.

While knockout mouse technology represents a valuable research tool, some important limitations exist. About 15 percent of gene knockouts are developmentally lethal, which means that the genetically altered embryos cannot grow into adult mice. This problem is often overcome through the use of conditional mutations. The lack of adult mice limits studies to embryonic development and often makes it more difficult to determine a gene's function in relation to human health. In some instances, the gene may serve a different function in adults than in developing embryos.

Knocking out a gene also may fail to produce an observable change in a mouse or may even produce different characteristics from those observed in humans in which the same gene is inactivated. For example, mutations in the p53 gene are associated with more than half of human cancers and often lead to tumours in a particular set of tissues. However, when the p53 gene is knocked out in mice, the animals develop tumours in a different array of tissues.

There is variability in the whole procedure depending largely on the strain from which the stem cells have been derived. Generally cells derived from strain 129 are used. This specific strain is not suitable for many experiments (e.g., behavioural), so it is very common to backcross the offspring to other strains. Some genomic loci have been proven very difficult to knock out. Reasons might be the presence of repetitive sequences, extensive DNA methylation, or heterochromatin. The confounding presence of neighbouring 129 genes on the knockout segment of genetic material has been dubbed the "flanking-gene effect". Methods and guidelines to deal with this problem have been proposed.

Another limitation is that conventional (i.e. non-conditional) knockout mice develop in the absence of the gene being investigated. At times, loss of activity during development may mask the role of the gene in the adult state, especially if the gene is involved in numerous processes spanning development. Conditional/inducible mutation approaches are then required that first allow the mouse to develop and mature normally prior to ablation of the gene of interest.

How to to improve your online security.

2013-03-27T23:45:00.002-04:00

Even if you're more tech-shy than tech-savvy, take heed to these easy-to-follow tips on how to beef up your online security.

With all the high-profile hacks, data breaches and malware (“malicious software”) in the news these days, you might be afraid to step a virtual foot into cyberspace.

The answer isn’t to avoid the Internet altogether – something that would be almost impossible today, anyway – but rather, you can take a few simple steps to ensure you and your data are as safe as they can be.

And no, you don’t need to be a computer engineer to bump up your online security.

The following are a handful of tips to help you get started.

1. Use antimalware software

Now that security software is bundled in Windows 8, not to mention many free versions available there really isn’t an excuse for not having an antimalware solution installed on your computer, which includes antivirus, antispyware, a firewall, and more.

Free services are better than none at all, of course, but there are much more robust online security solutions for about $40 a year – such as those offered by Symantec, McAfee and Kaspersky – that can detect, quarantine and remove more threats than free antimalware alternatives (plus they tend to catch a wider variety of malware, too). Paid services are usually updated more often, so you’re always protected from the latest threats, and are updated automatically rather than you having to remember to download the latest virus definitions.

Mac users, you aren’t out of the woods just because Mac attacks are more rare: you also need security software these days.

2. Password management

Creating a good password isn’t difficult, but it does take more time to come up with one than using common ones like “password,” “123456” or your kids’ or pet’s names – all of which are not recommended for obvious reasons. A strong password is at least 7 characters long, has a combination of letters, numbers and symbols and mixes upper and lower cases. It’s also a good idea to avoid real words or phrases.

And here’s an important tip: never, ever use the same password for all of your online activities — after all, once someone finds out one password, they’ve got the digital keys to unlock everything else of yours.

If you don’t want to use the recommended combination of letters, numbers and symbols, at least keep in mind single word passwords are easier to break than multiple word passwords. Instead of “walrus,” use something like “redwalrus” or “sillyredwalrusface.” Alternatively, use the first letter from a phrase – say, from a favourite song – so Macklemore & Ryan Lewis’ Thrift Shop (feat. Wanz) becomes “MRLTSFW.” This should be an easy password to remember – and better yet, add a number and symbol to this, too.

3. Opt for two-step authentication

Major tech companies like Google, Facebook and more recently, Apple, now offer a offer a two-step authentication process This serves as an extra security measure to protect your online accounts from being compromised. It confirms you – and only you – are granted access to your account.

How does it work? As the name “two-step authentication” suggests, in addition to a standard username and password you’ll also need a code that’s sent usually via text message to your mobile phone. Before you gain access to the site or app, you’ll be prompted to enter that short, randomly-generated verification code.

If this sounds too onerous, don’t worry. You can choose to have each computer you use secured once with this system, or if you prefer, you can be asked each and every time. Either way, you’ll be less likely to have your account compromised.

Instead of a text message, Google users can also download and install the Google Authenticator app on your Android, iPhone or BlackBerry.

4. Be cautious on Wi-Fi hotspots

Whether it’s at your favourite coffee shop, in an airport or a hotel lobby, millions of mobile computer users take advantage of the free public Wi-Fi networks – often referred to as “hotspots.” But there are a few tips for safer surfing.

Some Wi-Fi networks can appear to be legitimate — like an official McDonald’s hotspot or a Hilton hotel’s wireless network — when in fact they’re a fake. Nearby criminals, perhaps in a van outside, can create “rogue” networks that often contain the name of the store, hotel or airport, but actually will direct your information to their own computer. Before logging on, double-check it’s legit by confirming the network name at the establishment.

Always assume your Wi-Fi connections are being eavesdropped on. That is, if you’re surfing the web on your computer, smartphone or tablet at a coffee shop, do simple things like read the news. Don’t enter sensitive data – like online banking info — when browsing the web via a Wi-Fi network. In other words, why take the risk? If you can, also download and use free VPN (virtual private network) software, like Hotspot Shield to surf anonymously.

Another option is to bring your own network and resist the free Wi-Fi altogether. Specifically, all wireless carriers sell Internet sticks (sometimes referred to as “Turbo” or “Rocket” sticks) that snap into your laptop’s USB port and lets you access the Internet via cellular connectivity. Or you might turn your smartphone into a personal hotspot to get online, but be aware of data costs.

5. Talk to your kids about online security

Online security is all about common sense – so even if kids are more technical than mom and dad you can still remind them that many of the same “real world” do’s and don’ts are relevant on the Internet.

The first tip is to be cautious about posting and sharing personal information online — such as places like Facebook, Twitter or Instagram — especially information that could be used to identify you or locate you offline, such as your address, telephone number, what school you go to. Don’t post on your wall about a trip you’re excited about or you’re broadcasting the fact your home will be empty for a while. Also be cautious about what kinds of photos you’re posting, in case they reveal personal info such as a photo of you in front of your school or where you play soccer every week.

In fact, encourage kids to limit their social media use to friends only. Remind them that Twitter is always public. It’s not a popularity contest to see how many “friends” you have on Facebook.

Kids should be reminded not to give our their password to friends – a 2012 U.S. study found this is more common than you might think – as a best friend one day could be a bitter enemy the next.