Telescopes and Astronomy

A Three-Planet Month

noreply@blogger.com (Unknown) — Tue, 15 Feb 2011 12:11:00 +0200

Jupiter, Saturn, and Venus are the only planets visible to the unaided eye in February.

As evening twilight

fades after February days, the sole bright planet visible is Jupiter, prominent
in the southwest.
It sets a couple hours later, leaving the sky empty of any planets bright or
dim for a little while.
Then Saturn rises in the east, and it in turn is the only planet visible until
blazing Venus rises 2 or 3 hours before
sunrise.

DUSK

Jupiter comes into view at dusk less than halfway up the southwest sky
(for observers around 40°north
latitude). It dims slightly in February, to magnitude –2.1, and its apparent
diameter dwindles a bit to 34″.
There’s still much to check on its globe, however, including the status of
the South Equatorial Belt and the
Great Red Spot (SkyandTelescope.com/redspot). This is the last month
until July when Jupiter will be high
enough for good telescopic observations.

Jupiter crosses into the north celestial hemisphere on February 5th,
and late in the month it leaves Pisces
for a brief journey through the northwest corner of Cetus. Jupiter sets
around 9:30 p.m. as February opens
but around 8 pm as the month ends.

Uranus, faint at magnitude 6, had a close conjunction with Jupiter in
early January, but it begins February
almost 4° to Jupiter’s lower right. Jupiter’s swifter motion carries it to
6 from Uranus on February 14th
and almost 8½°by month’s end.

N IGHT

Saturn rises in the east in Virgo around 10:30 p.m. on February 1st and
two hours earlier on February
28th. The former is an hour after Jupiter sets, the latter only a half hour.
The ringed world brightens a l
ittle, from magnitude +0.7 at the beginning of February to +0.5 at month’s
end.

Saturn was less than 8°from Spica in late January, but now the planet is
moving westward (retrograding)
away from Spica.

ORBITS OF THE PLANETS

The curved arrows indicate each planet’s movement during February, as if you were looking down on the solar system from the constellation Ophiuchus. The outer planets don’t change position enough in a month to notice at this scale.

Saturn culminates (is highest in the south) around 4:30 a.m. at the start of February and 2:30 a.m. at month’s end. The rings are getting a bit narrower during February, but they’re still close to 10° from

edge-on.

DAWN

Venus rises while the sky is still fully dark throughout February, but the interval between Venus-rise and sunrise shrinks from 3 to 2 hours. Venus loses a bit of its tremendous luster this month, fading from magnitude –4.3 to –4.1. Its disk shrinks to less than 16″ in February, while its phase grows to more than 70% lit.

Venus glides eastward across Sagittarius this month, passing several stars and deep-sky objects.

Pluto is also in Sagittarius, but it’s too faint to view when it’s so low in the sky. Interestingly, however, Pluto is only 2.3° north of Venus on February 9th. Pluto is usually far in the sky from the major planets, but it has been approaching the ecliptic in recent years and will cross it in 2018. So for the next decade, Pluto will have many encounters with
planets.

Mercury, coming off a fine morning apparition in early January, rises only about 45 minutes before the Sun on
February 1st (for viewers around 40° north). On that date, can you detect the planet with binoculars just below the
crescent Moon very low in the southeast about 25 to 15 minutes before sunrise? Mercury is completely lost in the dawn
glow a few dawns later. It reaches superior conjunction with the Sun on February 25th.

Mars and Neptune also reach conjunction with the Sun this month, on February 4th and 17th, espectively. So both
are unobservable.

MOON PASSAGES

The Moon is a very slender crescent a few degrees above Mercury at dawn on February 1^st. A waxing crescent Moon shines to the right of Jupiter on the evening of February 6^th and above it on the 7th. The Moon is waning gibbous and rising in the late evening when it forms a triangle with Saturn and Spica on February 20th, and a vertical line with them on February 21st. The last-quarter Moon hangs to the left of Antares at dawn on February 25th. The waning lunar crescent is upper right of Venus at dawn on February 28th and lower left of Venus on March 1st.

Upcoming Solar Eclipse on January 4, 2011

noreply@blogger.com (Unknown) — Fri, 31 Dec 2010 16:46:00 +0200

Some of the world will be able to greet the first part of the new year with a solar eclipse. On the morning of Tuesday, January 4, 2011, an eclipse of the Sun will be widely visible across Europe and as far east as India. The eclipse won’t be visible in North and South America, however. Jay Pasachoff of Williams College in the US is the Chair of the International Astronomical Union’s Working Group on Eclipses, and says that even at a maximum, this eclipse will be only partial, with some of the Sun always visible. Because the Sun is too bright to look at safely, Pasachoff stresses that special solar filters or projection methods should always be used to protect the eyes.

Pasachoff will be in Tel Aviv to view the eclipse, and since partial eclipses are usually not very scientifically useful, he is looking forward to just enjoying the eclipse instead of scrambling to set up various scientific equipment.

“Partial eclipses are fun, and much more relaxing for a total-eclipse scientist like me, since the pressure on me is low and nothing happens too fast,” he told us. “Seeing a partial or other solar eclipse happen right on time, to the second, can be inspirational to students to study hard so that they, too, can understand the Universe.”

This will be Pasachoff’s 52nd solar eclipse.

Radio astronomers do find partial eclipses useful, as with a radio telescope, or in the ultraviolet or x-rays from spacecraft, scientists can use the timing of when solar active regions are covered and uncovered to study the structure of solar storms in better detail than is otherwise possible, Pasachoff said.

For this eclipse, people in Western Europe will find the Sun already eclipsed as the day begins, with the eclipse lasting about 80 minutes more. On January 4, the Moon will gradually cover the Sun, over a period of about 3 hours. At maximum, the eclipse will be at the horizon at sunrise in England, with 75% of the Sun’s diameter covered, and then gradually emerge over the next hour and 20 minutes. In Paris or Berlin, 80% of the Sun will be covered near sunrise. Farther east, the Sun will be a bit higher in the sky at maximum, 22° high with 67% covered in Athens. In Israel and Egypt, the Sun will be 33° high with over 55% coverage at maximum.

The most important thing, Pasachoff said, is to view an eclipse safely.

“Whenever the ordinary Sun is visible, even only part of it, you should not stare at it,” he said. “Special solar filters are available cheaply, or dense welders’ glass will do. Another method of seeing that the Sun is eclipsed is to punch a hole a few millimeters across in a piece of cardboard and hold it up to the Sun while you face away from the Sun and see the Sun’s image projected on the ground or onto another piece of cardboard. This method is called projection with a pinhole camera. It is rare that haze or clouds are sufficient to reduce the Sun’s intensity enough that one can see a partially covered Sun safely.”

2011 is unusual in that it has only four partial solar eclipses, for all of which the darkest part of the Moon’s shadow passes off the Earth’s surface. In 2012, an annular eclipse in which the Moon’s disk is a little too small to cover the entire Sun will pass from Japan over the Pacific to California and farther into the U.S. on May 20. On November 14, 2012, a total solar eclipse, in which it becomes dark as twilight, will start in northeastern Australia and cross a broad swath of the South Pacific.

The animation shown in the diagram to the right illustrates the motion of the shadow of the Moon at five minute intervals. This animation runs in a continuous loop.

This graphic, provided by Dr. Andrew Sinclair, shows the grey penumbral shadow where the eclipse will be seen as a partial one. The UT time is shown in the upper right-hand corner of the diagram.

The global visibility of this solar eclipse is shown in the diagram below.

Click to enlarge

Eclipses Of The New year 2011

noreply@blogger.com (Unknown) — Fri, 31 Dec 2010 15:41:00 +0200

by J. Kelly Beatty

After three consecutive years of enjoying time in the Moon's shadow, eclipse-chasers must go through withdrawal during 2011 because no total solar eclipses occur. However, the year kicks off with a deep partial solar eclipse that favors northern Europe, and a pair of total lunar eclipses come later on.

Few events in nature offer the drama and spectacle of a total solar eclipse, as demonstrated by this one seen over China on August 1, 2008.

S&T: Dennis di Cicco

A solar eclipse can only happen at new Moon, when the lunar disk passes directly between us and the Sun. Conversely, a lunar eclipse occurs during full Moon, when our satellite passes through Earth's shadow. These alignments don't occur at every new and full Moon because the lunar orbit is tipped about 5° to Earth's orbital plane — only occasionally do the Sun, Earth, and Moon line up exactly enough for an eclipse to occur. Three types of lunar eclipse are possible (total, partial, and penumbral) depending on how deep the full Moon plunges into or near the umbra, our planet's dark, central shadow. If it goes all the way in, we see a total lunar eclipse that's preceded and followed by partial phases. If the Moon skims part way into the umbra, only the partial phases occur. And if its disk passes just outside the umbra, it still encounters the weak penumbral shadow cast by Earth. (Oddly, four penumbral eclipses occurred last year.) Fortunately, no matter which type occurs, a lunar eclipse is observable anywhere on Earth where the Moon is above the horizon.
Because the Moon casts a smaller shadow than Earth does, eclipses of the Sun require observers to be in the right place at the right time. If the Moon completely hides the Sun, even for a moment, the eclipse is considered total. With its brilliant disk completely covered, the Sun's ghostly white outer atmosphere is momentarily revealed for anywhere from seconds to several minutes. However, this totality can only be viewed a narrow track or path on Earth's surface. Outside that path, about half the world is able to watch a partial eclipse as the Moon obscures a portion of the Sun.
Occasionally the Moon passes directly in front of the Sun but doesn't completely cover it. This odd-sounding situation is an annular eclipse, so-called because you can see a ring, or annulus, of sunlight surrounding the lunar disk. But an annular's path is likewise narrow, and outside of it observers see only a partial cover-up. No annular eclipses occur in 2011.
Interestingly, up to seven eclipses can take place in one year, and the last time that happened was 1982. The fewest possible is four, as was the case last year. Yet any given year can have only two "central" (annular or total ) solar eclipses, and again there was one of each in 2010.
Below are brief descriptions of this year's eclipses of the Sun and Moon.

January 4th's partial solar eclipse favors viewers in northern Europe, western Asia, and northern Africa. Blue lines show how much of the Sun's diameter is covered; green lines give Universal Time for mid-eclipse. Click on the image for a global view.

Fred Espenak

January 4: Partial Solar Eclipse
The year kicks off with a deep partial eclipse of the Sun that favors Europe (especially Scandinavia), northern Africa, and western Asia. Unfortunately, none of this event is visible from North America. Here's a sampling of cities offering good views, followed by the Universal Time of mid-eclipse at that location and how much of the Sun's disk is covered: Madrid (7:52, 47%), Paris (8:09, 65%), London (8:12, 67%), Stockholm (8:42, 79%), and Moscow (9:04, 75%). To see this eclipse at its maximum, you need to be in northeastern Sweden at 8:50:35 UT.
Skywatchers as far south as Nigeria and as far east as Mongolia have a chance to see the Moon's silhouette take at least a small bite out of the Sun.
June 1: Partial Solar Eclipse
A sequence of three syzygies over one month's time begins with a partial solar eclipse that falls across some of the world's least inhabited landmasses: Siberia, northern Canada, and Greenland. Mid-eclipse occurs at 21:17 UT. From the North Pole you'd see about one third of the Sun's disk covered by the Moon. Residents of Reykjavik, Iceland, can look forward to seeing 35% of the Sun's disk hidden near sunset. Alaskans north of Fairbanks and residents of northern New Brunswick and Nova Scotia have a chance to see slight divots in the Sun around midday and near sunset, respectively

The long-lasting total lunar eclipse on June 15, 2011, favors skywatchers in the Eastern Hemisphere.

Fred Espenak

June 15: Total Lunar Eclipse
Two weeks after a New Moon and a corresponding partial solar eclipse, the full Moon plunges deeply through Earth's umbra in the first of this year's total lunar eclipses. Totality lasts a whopping 100 minutes — nearly 40 minutes longer than the well-observed lunar eclipse in December 2010. The Moon is completely covered from 19:22 to 21:02 UT, and the partial phases begin one hour beforehand and end an hour afterward. To the chagrin of North American viewers, this timing places the June 15th event almost entirely over the Eastern Hemisphere, though viewers in eastern South America can see its later stages. July 1: Partial Solar Eclipse
The third event in this year's three-eclipse trifecta is a partial solar eclipse that few people, if any, can see. The path crosses the Antarctic Ocean well south of Africa, from which the Moon's indentation on the Sun's disk will be barely noticeable when mid-eclipse occurs at 8:38 UT.
November 25: Partial Solar Eclipse
Although the Moon takes a bigger bite of the Sun during November's event, the far-southern path is no better placed for viewing. Researchers at the South Pole can see about 75% of the Sun's diameter covered when the event peaks there at 6:30 UT. Slight partial phases can be seen from the southern tip of Africa just after sunrise and from Tasmania and southernmost New Zealand just before sunset.

Skywatchers in western North America have the best seats for the total lunar eclipse on December 10, 2011.

Sky & Telescope illustration

December 10: Total Lunar Eclipse
Year's end offers the finest spectacle of 2011 for skywatchers in the western U.S. and Canada: a total lunar eclipse before dawn. Totality extends from 6:06 to 6:57 a.m. PST (14:06 to 14:57 UT). The partial phase begins at 4:46 a.m. PST, when the Moon's leading edge enters the dark umbra of Earth's shadow, and the final bit of the Moon's disk exits the umbra at 8:18 a.m. But by then the Moon will have set (and the Sun risen) everywhere east and south of British Columbia. The entire eclipse is visible in the Pacific Ocean and much of Asia. Looking ahead to next year, 2012 will in some sense represent a reversal of fortunes from 2011. There'll be two central solar eclipses: an annular on May 20th (visible from the Pacific and western U.S.) and a total on November 13th (northeast Australia and South Pacific). But lunar eclipses will be limited to a partial event on June 28th and a barely-there penumbral eclipse on November 28th.

21st December 2010 Total Lunar Eclipse Photos

noreply@blogger.com (Unknown) — Wed, 22 Dec 2010 10:39:00 +0200

Space shuttle Discovery stands on Launch Pad 39A as the lunar eclipse takes place.

Stephen Edgar, Waterloo, Ontario

Dave Grass, southeastern Saskatchewan

Ramon Sasso, Santiago, Chile

The moon as seen from Southern NH, United States. Courtesy Marc Nozell 2008 Lunar Eclipse.

Matt D, New York City

Joseph Woodward, Grayslake, Illinois

Qatar Led Team Discovers Exoplanet

noreply@blogger.com (Unknown) — Thu, 16 Dec 2010 11:45:00 +0200

When listing the major scientific powers, the tiny nation of Qatar is not one that generally comes to mind. However, a Qatar astronomer, partnered with teams from the Harvard-Smithsonian Center for Astrophysics (CfA) as well as other institutions has just discovered a new exoplanet, dubbed Qatar-1b.

The planet itself, is another in the class of hot Jupiters which are massive, gassy planets that orbit their stars extremely closely. It has an orbital period of 1.4 days and is expected to be tidally locked with its parent star, a K type star.

It was discovered by a set of wide angle cameras located in New Mexico which are capable of surveying a large number of stars at a single time. The goal was to find planets that eclipsed the parent star and would thus show regular variations in their light curve. Images taken from this system were then sent to teams working at Universities in St. Andrews, Leicester, and Qatar. These teams processed the images and narrowed the stars down to a list of a few hundred candidates to be studied further.

From there Dr. Khalid Al Subai as well as the Harvard CfA team used the Smithsonian’s Whipple 48-inch telescope to more accurately measure the transits as well as as their 60-inch telescope to make spectroscopic observations to weed out binary star systems. These observations confirmed the existence of the planet.

“The discovery of Qatar-1b is a great achievement — one that further demonstrates Qatar’s commitment to becoming a leader in innovative science and research,” said Al Subai. Indeed, in the past 15 years, Qatar has undergone a large revolution towards science and education. Many universities have begun to open remote campuses, including Carnegie Mellon and Texas A&M.

“The discovery of Qatar-1b is a wonderful example of how science and modern communications can erase international borders and time zones. No one owns the stars. We can all be inspired by the discovery of distant worlds,” said CfA team member David Latham.

Landfall at Santa Maria for Opportunity on Mars

noreply@blogger.com (Unknown) — Thu, 16 Dec 2010 11:23:00 +0200

NASA’s Opportunity Mars rover arrived yesterday (Dec .15) at Santa Maria crater on Sol 2450. She sits just 20 meters from the crater rim. A multitude of inviting rocks and boulders are strewn about the 80 meter diameter crater, making this a Martian geologists dream.

And so it goes too for a Martian photographer with lots to shoot and with the giant 14 km wide Endeavour crater serving as backdrop and coming into ever clearer focus.

Santa Maria is just 6 km from the western rim of Endeavour (see panoramic mosaics above and below).

Opportunity has been on a swift advance since departing from Intrepid crater in mid-November and driven about 1.5 km over very smooth terrain. The rover continues to benefit from a bounty of solar power and upgraded software enabling longer and more frequent days of drives. Opportunity has now driven a total of 26.4 km.


Add caption

The rover team is planning for an extensive and multi week science campaign at Santa Maria using all the instruments and cameras at their disposal.

Opportunity will spend the holiday season and the upcoming Solar conjunction exploring around Santa Maria according to Matt Golembek, Mars Exploration Program Landing Site Scientist at the Jet Propulsion Laboratory (JPL), Pasadena, Calif.

There will be no uplink commanding to the spacecraft around the actual conjunction period from Jan. 28 to Feb. 12 (UTC) out of caution that the command transmission could be disrupted.

The team plans a sophisticated wide-baseline stereo-imaging survey of Santa Maria by having Opportunity drive to several positions halfway around the crater. A mineral survey will be carried out using the spectrometers, microscope and drill – known as the RAT or rock abrasion tool – located at the terminus of the rover’s robotic arm.

The rover is now at the two thirds mark of a 19 km (12 mile) journey from Victoria crater on the road to reach the rim of the scientifically rich environs of Endeavour crater sometime later in 2011. Opportunity explored the rim and interior of Victoria from mid-2006 to mid-2008.

Santa Maria is the largest feature that Opportunity will explore between Victoria and Endeavour craters. The team assigns informal names to craters visited by Opportunity based on the names of historic ships of exploration in human history. See Opportunity traverse maps below.

More than 95 percent of the data from Spirit and Opportunity are relayed by NASA’s Mars Odyssey orbiter. Today, Odyssey broke the record for being the longest-serving spacecraft at the Red Planet during it’s 3,340th day in Martian orbit.

Wininners of Astronomy’s 2010 photo contest

noreply@blogger.com (Unknown) — Sat, 11 Dec 2010 12:48:00 +0200

The results are in. Four individuals from four countries took home the prizes in Astronomy magazine’s 2010 Astroimaging Contest. Astronomy editors chose the winning images.

The overall winner is Thomas Bader of Rheinfelden, Germany. His image from Hao Island in French Polynesia of the eclipsed Sun taken during the July 11, 2010, total solar eclipse shows incredible detail, both in the Sun’s corona (outer atmosphere) and on the Moon’s surface, where features shining from light reflected off Earth are easily visible during totality. For his image, Bader wins a Celestron CPC 1100 GPS XLT 11-inch Schmidt-Cassegrain telescope.

he winner in the General category is Tunç Tezel of Bursa, Turkey. His image of the southern Milky Way from Mangaia, one of the Cook Islands in the South Pacific, shows the closest star system to Earth, Alpha Centauri, the Southern Cross, the Magellanic Clouds (two of our galaxy’s satellites), and thousands upon thousands of other stars. Tezel wins a DMK 21AU04.DS CCD camera courtesy of Imaging Source.

In the Deep-sky category, longtime Astronomy magazine contributor Ruben Kier of Orange, Connecticut, bested the competition. His superb image shows three galaxies — M65, M66, and NGC 3628 — collectively called the Leo Trio because of the constellation in which they reside. Kier wins a DMK 41AU02.AS CCD camera from Imaging Source.

Top honors in the Solar System category go to Li-Chun Chen of Taipei, Taiwan. He combined 32 exposures of the July 11, 2010, total solar eclipse from Hao Island in French Polynesia into one dramatic image that documents the event. Chen wins a DMK 31AU03.AS CCD camera contributed by Imaging Source.

Astronomy magazine Photo Editor Michael E. Bakich talked enthusiastically about the participation: “This year’s entries — 77 in all — went way beyond expectations. I received submissions from longtime contributors and also from many people who had never sent the magazine an image before.”

The Geminid Meteor shower of December 13th (Winter’s Fireworks)

noreply@blogger.com (Unknown) — Wed, 8 Dec 2010 12:47:00 +0200

Early to mid December is the time for the yearly Geminids meteor shower, so named as its radiant appears to be the constellation Gemini. First observed only about 150 years ago, the Geminids are thought to be getting more intense each passing year. The shower is expected to peak around the 13th (next Monday night) this year, with great viewing from the 9th through the 13th.

The Geminids are unusual in that they are not caused by debris from a comet, but from 3200 Phaethon, an Apollo asteroid. Discovered October 11, 1983, 3200 Phaethon is the first asteroid discovered by a spacecraft, and it approaches closer to the sun than any other numbered asteroid.

The Geminids (also known as Winter’s Fireworks) are somewhat slow moving, bright yellowish in color. They are considered the most consistently active meteor shower; and this year will offer prime viewing conditions. The moon will be in its first quarter, setting several hours before sunrise.

Amateur viewers are expected to be able to catch 100 – 120 streaks per hour at the most active times. Expect Earth grazers as Gemini rises, right after sunset, especially on the 13th. The action should pick up from about midnight until dawn (applicable for all time zones), as Gemini moves overhead.

I have my thermos ready to go!

Total Lunar Eclipse of December 21st

noreply@blogger.com (Unknown) — Sun, 5 Dec 2010 18:30:00 +0200

Total Lunar Eclipse

The last lunar eclipse of 2010 is especially well placed for observers throughout North America. The eclipse occurs at the Moon's descending node in eastern Taurus, four days before perigee.

The Moon's orbital trajectory takes it through the northern half of Earth's umbral shadow. Although the eclipse is not central, the total phase still lasts 72 minutes. The Moon's path through Earth's shadows as well as a map illustrating worldwide visibility of the event are shown in the following figure . The timings of the major eclipse phases are listed below.

The white areas represent where the eclipse will be seen

Penumbral Eclipse Begins: 05:29:17 UT

Partial Eclipse Begins: 06:32:37 UT

Total Eclipse Begins: 07:40:47 UT

Greatest Eclipse: 08:16:57 UT

Total Eclipse Ends: 08:53:08 UT

Partial Eclipse Ends: 10:01:20 UT

Penumbral Eclipse Ends: 11:04:31 UT

At the instant of greatest eclipse (08:17 UT) the Moon lies near the zenith for observers in southern California and Baja Mexico. At this time, the umbral magnitude peaks at 1.2561 as the Moon's southern limb passes 2.8 arc-minutes north of the shadow's central axis. In contrast, the Moon's northern limb lies 8.1 arc-minutes from the northern edge of the umbra and 34.6 arc-minutes from the shadow center. Thus, the southern half of the Moon will appear much darker than the northern half because it lies deeper in the umbra. Since the Moon samples a large range of umbral depths during totality, its appearance will change dramatically with time. It is not possible to predict the exact brightness distribution in the umbra, so observers are encouraged to estimate the Danjon value at different times during totality. Note that it may also be necessary to assign different Danjon values to different portions of the Moon (i.e., north vs. south).

The entire event is visible from North America and western South America. Observers along South America's east coast miss the late stages of the eclipse because they occur after moonset. Likewise much of Europe and Africa experience moonset while the eclipse is in progress. Only northern Scandinavians can catch the entire event from Europe. For observers in eastern Asia the Moon rises in eclipse. None of the eclipse is visible from south and east Africa, the Middle East or South Asia.

The December 21 total lunar eclipse belongs to Saros 125 a series of 72 eclipses in the following sequence: 17 penumbral, 13 partial, 26 total, 9 partial, and 7 penumbral lunar eclipses (Espenak and Meeus, 2009). Complete details for the series can be found at:

eclipse.gsfc.nasa.gov/LEsaros/LEsaros125.html

December 21st's Total Lunar Eclipse

This month's picks of the very best astrophotos.

noreply@blogger.com (Unknown) — Thu, 2 Dec 2010 18:23:00 +0200

The Crescent Nebula

GORDON HAYNES

HEREFORD, JULY 2010

Gordon says: "I like the contrast of the blue of the crescent compared to the reddish colours of the surrounding hydrogen clouds, which helps to highlight the different gases present. The wide-field view afforded by my equipment gives more context to the size of the Crescent compared to its surroundings."

Equipment: Takahashi FSQ-106ED refractor with a Starlight Xpress SXVF-H36 CCD camera on a Paramount ME mount.

Sky at Night Magazine says: "The vibrancy of Gordon's imoge is wonderful. We love the great detail seen in the tendrils af faint and tenuous gas surrounding the Crescent."


The Crescent Nebula

The North American Nebula

IAN DUNBAR

SALISBURY, AUGUST 2010

Ian says: "I particularly like the backdrop of a moss of Milky Way stars and the intricacies of the dark dust threads that weave their way through the bright nebulae. It's a beautiful area of the sky."

Equipment: William Optics ZS80FD refractor with a modified and cooled Canon EOS 4500 DSLR camera mounted on an EQ6 mount.


The North American Nebula

The Moon

PETROS OIAMANTOPOULOS

LOUTRAKI, GREECE, 31 JULY 2010

Petros says: "I don't usually do any astrophotography when the Moon is up. This time, however, I decided to try something different and used my CCO camera to capture the Moon. After experimenting with various filters and exposure times I took this image through a hydrogen alpha filter."

Equipment: Takahashi TOA-130 refractor and an SBIG ST-2000XM CCO camera on an Astro-Physics 1200GTO mount.

The Moon

The Milky Way and the Aurora

FREORIK BROMS

KVALOYA, NORTHERN NORWAY, 23 OCTOBER 2009

Fredrik says: "With this wide-angle shot I wanted to capture the feeling of escaping a light-polluted place. I am very fond of the feeling of silence that I feel I have been able to capture in this image”.

Equipment: Nikon 03 OSLR camera with an AF-Nikon 20mm lens on an AstroTrac TT320X mount.


The Milky Way and the Aurora

Stars in Motion

MIGUEL CLARO

VILA BOIM, PORTUGAL, 19 JULY 2010

Miguel says: "To record the motion of the stars in the region of the celestial pole, I stocked 328 images, each a 30-second exposure. It was the longest exposure I've done so far, a total integration of 2 hours 44 minutes. The 1ight drawings' were made with a red and while lantern when I passed by."

Equipment: Canon EOS SOD OSLR camera with a Sigma EX HSM 10mm lens.

Stars in Motion

Jupiter and moons

MARC DELCROIX

TOURNEFEUIL1E, FRANCE, 8 JULY 2010

Marc says: "This image is a montage of Jupiter's moons in IR and Jupiter in RGB. From left to right you can see 10, Jupiter, Europa and Ganymede (with Golileo Regia)."

Equipment: Meade LX200 254mm Schmidt-Cassegrain telescope with a 2x Barlow lens and a Lumenera SKYnyx 2-0M camera.

Jupiter and moons

The outstanding beauty of the Milky Way

noreply@blogger.com (Unknown) — Tue, 30 Nov 2010 22:25:00 +0200

The Milky Way over Haleakala Crater on Maui. Click for a larger version. Photo by Wally Pacholka via National Geographic

Astronomers turn their telescopes to the unbounded beauty of the Milky Way.

Our galaxy is far larger, brighter, and more massive than most other galaxies. From end to end, the Milky Way's starry disk, observable with the naked eye and through optical telescopes, spans 120,000 light-years. Encircling it is another disk, composed mostly of hydrogen gas, detectable by radio telescopes. And engulfing all that our telescopes can see is an enormous halo of dark matter that they can't. While it emits no light, this dark matter far outweighs the Milky Way's hundreds of billions of stars, giving the galaxy a total mass one to two trillion times that of the sun. Indeed, our galaxy is so huge that dozens of lesser galaxies scamper about it, like moons orbiting a giant planet.

As a result of its vast size, the Milky Way can boast at least one planet with intelligent life. Giant galaxies like the Milky Way and the nearby, even larger Andromeda galaxy possess the power to create and retain a rich supply of iron, oxygen, silicon, magnesium, and other elements heavier than helium. Forged by the Milky Way's abundant stars, such heavy elements are the building blocks of terrestrial planets.

Clash of the Titan Galaxies

noreply@blogger.com (Unknown) — Mon, 29 Nov 2010 18:46:00 +0200

NGC 520 — also known as Arp 157 -- is actually a mashup of two gigantic galaxies. Credit: ESO

Is this galaxy exploding? Although that’s what it might look like, this is actually two gigantic galaxies crashing into each other. NGC 520 — also known as Arp 157 — is a mashup of two huge galaxies, now combining into one. We can’t really watch the process, as it happens extremely slowly — over millions of years, and the whole process started about 300 million years ago. Apr 157 is about 100,000 light-years across and is now in the middle stage of the merging process, as the two nuclei haven’t come together yet, but the two discs have. The merger features a tail of stars and a prominent dust lane. NGC 520 is one of the brightest interacting galaxies in the sky and lies in the direction of Pisces (the Fish), approximately 100 million light-years from Earth.

This image was taken by the ESO Faint Object Spectrograph and Camera attached to the 3.6-metre telescope at La Silla in Chile.

You’d need a about a 4-inch telescope to see this 12th magnitude object yourself. Here’s the location: RA: 1h 24m 35.1s, Declination: +03° 47? 33?. Or put in those coordinates in Google Sky to see it there.

Source: ESO

DON'T MISS ... 3 TOP NIGHTSKY SIGHTS

noreply@blogger.com (Unknown) — Fri, 26 Nov 2010 18:47:00 +0200

Total lunar eclipse

WHEN: 21 December, 05:00 to 08:30

During totality the Moon is completely in the Earth's umbral shadow

A TOTAL ECLlPSE of the Moon takes place in the early hours of 21 December. Such an event can only happen when the Sun, Earth and Moon are perfectly aligned, Viewing the eclipse will be tricky since the Moon will be setting as the eclipse really gets underway.

The Earth's shadow has two parts due to the fact that the Sun isn't a point source of light as seen from Earth. The main 'dark' or umbral shadow is in the form of a cone stretching out behind the Earth in the opposite direction to the Sun, as shown in the diagram. Surrounding this is another region of less intense shadow known as the penumbra. Look back at the Sun from within the penumbral shadow and you'd see only part of the Sun's disc covered. In the umbral shadow, the entire Sun appears covered.

At the distance of the Moon, the cross-section of these two shadows appears as two concentric circles: all inner dark umbral circle about three times the apparent diameter of the Moon, surrounded by a fainter penumbral circle about five times the apparent diameter of the Moon. The Moon enters this bull's-eye cross-section on the morning of 21 December.

The penumbral eclipse starts at 05:27 GMT when the Moon is about 23° up in the west as seen from the centre of the UK. However, because the penumbral shadow isn't very dark, it doesn't much change the visual appearance of the Moon. Having said that, the left-hand edge of the Moon will begin to take on a subtly darker shade just before the Moon enters the darker umbral shadow at 06:32.

The main umbral part of the eclipse begins with the Moon 14° above the horizon, and this marks the start of the partial phase of the eclipse. Totality occurs at 07:40, when the Moon's entire disc will be immersed in the umbral shadow. Its altitude at this time will be just 5° and the sky will be starting to get bright.

The Moon never goes completely dark because some light from the Sun is refracted, or bent, as it passes through the Earth's atmosphere. The blue component of this light gets scattered, leaving mainly red to fill in the umbral shadow. The result will be a reddened Moon, close to the northwestern horizon. Mid-eclipse occurs at 08:12 and from the centre of the UK, the Moon sets soon after.

Geminid meteors

WHEN: Peak on 13/14 December

THE GEMINIDS is probably the finest meteor shower of the year with a dependable Zenithal Hourly Rate (ZHR) of around 100 meteors per hour. They all appear to emanate from a point in the sky known as the radiant, which in the case of the Geminids lies close to the star Castor, as shown in the chart. The shower is active from 6-19 December, with peak rates occurring in the early hours of 14 December, close to when the radiant is at its highest point in the sky.

The best way to observe the shower is to lie on a sunbed and look up at a large area of sky. Being December, it's important to make sure you wrap up warm before venturing outside for any length of time. Choose the darkest location you can find away from any lighting, lie back and wait. The only thing you need to enjoy the Geminids is your eyes and plenty of patience! Although you could see a meteor anywhere, looking in the direction of Orion for a couple of hours after midnight and then switching to look at Leo until dawn would be our recommendation.

The first quarter Moon will look gorgeous on the night of 13 December, sitting just 6° north of mag. -2.3 Jupiter. However, its light will drown out some of the early meteor. Thankfully, the Moon sets at around 00:30 on 14 December, and from this time until dawn is the best period to view the Geminids. The shower produces medium to slow meteors with a good proportion of bright trails. This means that the Geminids make excellent photographic subjects.

Asteroid 7 Iris and M67

WHEN: Visible all December; view around midnight

THE ASTEROID 7 IRIS will be located in the constellation of Cancer the Crab throughout December and will pass quite close to the mag. +6.9 open star cluster M67. A collection of stars loosely held together by their mutual gravity, this object is one of the more ancient open clusters in our Galaxy, and is thought to be around 4 billion years old.

lris brightens from mag. +8.9 at the start of December to +8.3 by the end and should be easy to pick out with binoculars or a small telescope using a low-power eyepiece. This is a fairly sparse region of the sky so it shouldn't be too difficult to spot Iris as it moves from day to day among the background stars. The best way to confirm you've seen it is to observe the suspected region several days apart, drawing or photographing the main 'stars' you can see. If one of those stars moves between your observations then that should be Iris.

The asteroid's track swings quite close to M67, taking it within a degree of the cluster's centre between 13- 25 December. At its closest approach on 2L December, it sits about 45 arcminutes from the cluster's centre, unfortunately coinciding with the full Moon!

Viewing the aurora from space: Earth aurora and Saturn Aurora

noreply@blogger.com (Unknown) — Thu, 25 Nov 2010 19:16:00 +0200

All images via NASA

You’ve seen amazing images of the Aurora Borealis and its counterpart, the Aurora Australis, but now you have a chance to see them as never before: from space. If you think the view down on Earth is incredible beyond words, wait until you see what these natural light phenomena look like from the International Space Station and through the lens of the Hubble Telescope.

Auroras are created when charged particles from the sun, called the solar wind, interact with the magnetic shield that surrounds our planet (and other planets as well). On Earth, this magnetic shield, called the magnetosphere, protects us from radiation by pushing the solar wind around it. Electromagnetic waves and electric fields are created, then transfer their energy into electrons that interact with oxygen and nitrogen to create the beautiful natural light display we know as Aurora.

Beautiful Aurora Borealis

The Aurora Borealis was named by Pierre Gassendi in 1621 after Aurora, the Roman goddess of dawn, and Boreas, the Greek name for north wind. The Cree called it the “Dance of the Spirits.”

< In this picture of the Aurora Borealis, the Manicouagan Impact Crater, located in northern Canada, can be seen 300 km below. International Space Station Science Officer Don Pettit said that “changing auroras appeared to crawl around like giant green amoebas” in orbit.

Auroras become more visible the closer one gets to either the north or south poles. At these extreme ends of the Earth, they may appear high up in the sky overhead, but farther away, they seem to rise up from the horizon as a green glow with tinges of red, like the “red crown” of Aurora Australis, seen in the picture below. This image almost looks like a treasure map: follow the trail and get to what looks like a legendary castle from space.

Follow the Trail

Another image of the southern lights almost looks like loops of light created by huge glow sticks (Below);

Loop de loop

and here’s the amazing view that the astronauts at the International Space Station get to see:

An Astronaut’s View

In the image below, the view of the Aurora Borealis from the International Space Station includes the shining lights of Finland, Russia, Estonia and Latvia. The Praesepe or Beehive Cluster in the constellation Cancer can be seen to the lower right of the moon, with Saturn to the right of that.

Take Me To the Moon

And if you thought Auroras were spectacular on Earth, check out these two pictures of amazing light shows on Jupiter and Saturn:

Auroras on Jupiter and Saturn

Aurora on Jupiter


Aurorae on Saturn

This incredible image of Saturn features its famed rings and Auroras at either end of the planet.

Beginners' guide to: Your first five sights

noreply@blogger.com (Unknown) — Mon, 22 Nov 2010 19:18:00 +0200

Beginners' guide to ...

Your first five sights

Tooled up and ready to go, but don't know where to aim your scope? Here's our list of the top sights.

THE BASICS

What are the best objects to aim at for your first nights at the telescope? Where you need to look in the night sky to find them. How you can get the most out of your first Foray into stargazing

The long winter nights mean it's a great time of year for stargazing, with the sky filled with some real celestial gems. If you've just bought a telescope or have asked for one, you'll no doubt want to get out there and start using it. However, faced with the countless points of light in the night sky, it can be a daunting task to decide what to aim your telescope at first.

To make sure you're suitably impressed, we've highlighted five top sights that arc around at the moment. We've explained where and when to search for them, and what to look for. This list will also give you a good taste of the range of objects you can point your telescope at.

Heading up our list is the Moon – the best place for any fledgling astronomer to start is our nearest celestial neighbor, You haven't really seen this familiar celestial body until you've viewed it with a telescope; its rugged, crater- marked surface will keep you coming back to your new scope for more.

You'll then need to bag yourself a planet and Jupiter, the largest of them all, will be a stunning sight. We then take you to deep space and the famous Orion nebula, a huge cloud of gas and dust hanging in Orion's Sword. Indeed, a relatively cheap telescope with an aperture of 3 to 6 inches will show you a wide variety of astronomical objects, and our final two targets are a distant galaxy and a pair of star clusters.

You could just rush outside and get going. But, with a little preparation, your session can be even more enjoyable. Once you're at the scope, with your eye properly adjusted to the dark after 20 minutes or so outside, you're ready to go.

What you won't see are grand, colorful objects that look like the stunning space images you see in books. However, what you do get is an amazing feeling as you find the e incredible objects for yourself.

Your first telescope targets

Ready? Take aim ... Go! Read on to find the top five astronomical objects for beginners

The moon

THE MOON

Constellation: It doesn't stay in the same place but it's hard to miss

When to view: 8 to 17 December and 8 to 17 January

These dotes cover the waxing phases of the Moon in the evening skies, from the date when it is first seen as a thin crescent emerging after sunset. The reason you want to look at this time is because the terminator is visible. This is the line between the lighted side and the dark side of the Moon and the place where the Sun's light catches the craters and mountain ranges, thus casting amazing shadows across the lunar surface.

JUPITER


Jupiter

Constellation: moving from Aquarius into Pisces in the south

When to view: as soon as it's dark

Jupiter is unmistakable as there are no bright stars in the area where it sits. Through a small telescope, you can see the planet as a disc with several dark bands of its atmosphere. You may also see Jupiter's four largest moons as points of light either side of the planet.

ORION NEBULA, M42

Constellation: Orion

When to view: from 9pm at the start of December

Orion Nebula

The Orion Nebula, numbered 42 in the famous Messier Catalogue of deep-sky objects, is a 'must' for observing the winter skies. The Orion Nebula is just visible to the unaided eye as a misty patch, but even the smallest of scopes will start to reveal the sweeping structure of this stellar nursery. You will see it as a wonderful curving cloud of dust and gas.

ANDROMEDA GALAXY, M31

Constellation: Andromeda

Andromeda Galaxy M31

When to view: as soon as it's dark, high in the sky

M31 is found by star-hopping from the nearby asterism, the Great Square of Pegasus. This will appear as a misty patch to the eye but is actually a giant, spiral island of stars, similar to our own Milky Way Galaxy. What is so impressive about the Andromeda Galaxy is that what you are looking at sits at around 2.75 million light-years away - a staggering distance.

SWORD HANDLE (DOUBLE CLUSTER) NGC 869 & NGC 884

Constellation: Perseus

When to view: as soon as it's dark

SWORD HANDLE (DOUBLE CLUSTER)

The Sword Handle will be very high in the east and moves almost overhead through the night. To find the Sword Handle, locate the 'W'-shape of Cassiopeia and work from there. In a darker location, it's just visible with the unaided eye. With a small telescope it's a wondrous sight of two amazing, roundish concentrations of hundreds of stars.

ISS crew captures spectacular view of earth’s atmosphere

noreply@blogger.com (Unknown) — Sun, 21 Nov 2010 18:27:00 +0200


A breathtaking new image taken by astronauts on the International Space Station clearly shows the various layers of Earth's atmosphere during sunset over the Indian Ocean.

A brilliant sequence of colors in the image denotes each of the layers of Earth's atmosphere, which are visible here because the picture was taken while the space station had an edge-on, or limb, view of the Earth. From this vantage point, the Earth's curvature can also be made out.
The troposphere — the lowest layer of Earth's atmosphere and the one in which humans dwell and weather occurs — appears in deep oranges and yellows. The troposphere can extend from the planet's surface to a height between 3.5 to 12.5 miles (6 and 20 km).
This lowest layer contains more than 80 percent of the mass of the atmosphere and almost all of the water vapor, clouds, and precipitation.
Several dark cloud layers are visible within this layer in the image. Variations in the colors are due mainly to varying concentrations of either clouds or aerosols (airborne particles or droplets).
Next up is the stratosphere, which appears as a pink to white region above the clouds. This atmospheric layer generally has little or no clouds and extends up to approximately 30 miles (50 km) above the Earth's surface.
The stratosphere is also home to the layer of ozone that protects the Earth's surface and the creatures that live on it from the sun's harmful ultraviolet rays.
Above the stratosphere, blue layers mark the upper atmosphere (including the mesosphere, thermosphere, ionosphere, and exosphere) as it gradually fades into the blackness of outer space.
The astronaut aboard the space station was facing west when they snapped this picture. Astronauts in low-Earth orbit see 16 sunrises and sunsets every day due to their high orbital velocity (more than 17,000 mph, or 28,000 kph).

Aurora Alert! Solar Flare Heading Our Way!

noreply@blogger.com (Unknown) — Sun, 14 Nov 2010 18:40:00 +0200

This image shows a three and a half hour (0000 - 0330 UT) time lapse movie of the flare and filament event. Credit: NASA/SDO

An active sunspot (1123) erupted on (Nov. 12th), producing a C4-class solar flare and apparently hurling a filament of material in the general direction of Earth. Coronagraph images from the Solar and Heliospheric Observatory (SOHO) and NASA’s twin STEREO spacecraft show a faint coronalsun-Earth line. The cloud could deliver a glancing blow to Earth’s magnetic field sometime on Nov. 14th or 15th. High latitude sky watchers could see auroras on those dates.

New sunspot 1123 in the Sun's southern hemisphere is crackling with C-class solar flares. Credit: SDO/HMI.

Here’s a look at the two sunspots currently visible on the Sun.

Taurid meteors, get your binoculars ready.

noreply@blogger.com (Unknown) — Sat, 13 Nov 2010 17:21:00 +0200

WHEN: Over peak periods between 22:00 and dawn

The radiant positions of the Northern and Southern Taurids throughout November in the constellation of Taurus -look out for bright fireballs!

THE TAURID METEOR Shower is active at the start of November and, with a new Moon on the 6th, the conditions are favorable this year. Shower meteors appear to emanate from a single area of the sky known as the shower radiant, but in the case of the Taurids there are two separate radiants.

The Northern Taurids are active from 12 October to 2 December and show peak activity from 4-7 November. The Southern Taurids are active from 17 September to 27 November and show peak activity from 30 October to 7 November, Even at their peak, both showers are relatively weak with zenithal hourly rates of around 7 meteors per hour. This means you might see 1-3 meteors per hour if you're lucky. Low though these figures are, the Taurids do have a couple of compelling features that definitely make them worth watching out for.

First, the peak of both showers lasts over several nights. Contrast this with the August Perseids, which show a sharp rise in activity over just one night. Second, it is thought that the main swarm of sand grain-sized particles that give rise to the Taurids is accompanied by a swarm of pebble-sized particles. These can produce meteor fireballs - a spectacular sight.

Hunting down alien volcanoes

noreply@blogger.com (Unknown) — Thu, 11 Nov 2010 23:58:00 +0200

Hubble's successor could spot eruptions on extrasolar planets

NASA'S JAMES WEBB Space Telescope (JWST), due for launch in 2014, could spot the tell-tale signs of violent volcanoes erupting on alien planets. Astronomers are still decades away from being able to image the surface of an extrasolar planet. But they have been able to see chemical signatures of certain gases in the atmospheres of gas giants orbiting close to their stars.

Violent landscape: intense volcanic eruptions that the next generation JWST

could spot on an extrasolar planet

A new theoretical study by scientists at the Harvard-Smithsonian Center for Astrophysics in Massachusetts now suggests that JWST could detect sulphur dioxide from very explosive eruptions on nearby exoplanets. Large amounts of the gas would be produced by the eruptions and sulphur dioxide is very slow to wash out of the air.

"You would need something truly earth-shaking, an eruption that dumped a lot of gases into the atmosphere," says team member Lisa Kaltenegger. She estimates that JWST could detect a volcanic eruption 10 to 100 times as powerful as the 1991 eruption of Mount Pinatubo in the Philippines, provided it was on a planet circling a nearby star. www.jwst.nasa.gov

FOUND: POTENTIALLY HABITABLE WORLD

noreply@blogger.com (Unknown) — Thu, 11 Nov 2010 18:45:00 +0200

An artist's impression of the planet Gliese 581g

JUST AS THIS issue was going to press, the news we'd been eagerly anticipating was announced: the discovery of the first Earth-like planet with the potential to be habitable. The mass of Gliese 581g is around four times that of Earth so it's likely to be rocky, with sufficient gravity to retain an atmosphere. It is squarely in the middle of its star's 'habitable zone' - a region in which liquid water could exist on the surface.

Gliese 581g is tidally locked, so that one side faces the star while the other is always in darkness. If there is any life there, the line between the light and shadow (the 'terminator') is where it's most likely to be found. The discovery was based on 11 years' worth of observations with the WM Keck Observatory in Hawaii. www.ucsc.edu

DON'T MISS ... TOP SIGHTS, WITH TIMES AND DATES

noreply@blogger.com (Unknown) — Wed, 10 Nov 2010 21:54:00 +0200

WHEN: Various times and dates throughout November

THE FOUR LARGEST satellites of Jupiter are known as the Galilean moons after their discovery by Galileo Galilei in 1610. The moons appear to flit from one side of the planet to the other in an unceasing celestial ballet. As they get close to the planet, their discs and shadows create interesting events that can be seen with small telescopes.

Io and Europa orbit the planet relatively quickly in periods of 1.77 and 3.55 days respectively; Europa's period being twice that of Io, This means that events between these moons and Jupiter take place fairly frequently.

The next moon out is Ganymede, the largest moon in the Solar System. With an orbital period of7.15 days, Ganymede takes twice as long as Europa to orbit Jupiter, so its events are less common. There are plenty of Ganymede-related events occurring on the evening of 3 ovember. As the sky darkens, the giant moon will be behind the planet, reappearing at 16:58 in an event known as an occultation reappearance (OcR). An hour later, Ganymede will dramatically fade from view as it enters Jupiter's shadow. This event, known as an eclipse disappearance (EcD), marks the start of an eclipse of Ganymede that will continue until 20:58, when an eclipse reappearance (EcR) restores the moon to view. As an added bonus, at 19:43, Jupiter's innermost moon, Io, can also be seen coming out of eclipse. Use the charts below to find the events on specific dates and times.

Being so large, Ganymede's shadow is impressive when it crosses Jupiter's disc, and you'll have a chance to see it on the evening’s of 21 and 28 November. Ganymede's shadow transit will be underway as the sky darkens on the 21st, and the event comes to an end at 19:1J. with a shadow transit egress (ShE).

On the 28th, Ganymede itself can be seen exiting off Jupiter's disc at 18:05, an event known as a transit egress (TrE). This is followed by the appearance of Ganymede's shadow on the disc, a shadow transit ingress (ShI), at 20:21. The shadow remains visible until it leaves the disc at 23:J 2; a shadow transit egress (ShE).

The outermost Galilean moon, Callisto, takes 16.6 days to orbit Jupiter. On 20 November; if the skies are clear, you should be able to see Callisto just clip the southern part of Jupiter’s disc, starting with a transit ingress (TrI) at 20:38 and ending with a transit egress (TrE) at 21:13.

Observing Plans and Techniques

noreply@blogger.com (Unknown) — Sun, 7 Nov 2010 18:47:00 +0200

Before You Start

Having a plan or an idea as to what you wish to observe can save you a lot of time fiddling around in the dark. By looking at a star chart or computer software one can devise one’s own observing program for an evening’s viewing. Alternatively, there are a number of books available that contain suggested sky tours and interesting observing programs.

Having such a plan can save you a lot of time on the night. It can be very frustrating, having

set up for a night’s viewing, to have spent half an hour deciding what to look at, only to look up and see the clouds roll in!

As an astronomer you are probably very meteorologically aware. After looking at the weather forecast on the television or the Internet, check any satellite footage. This is invaluable for us astronomers and is an area where the Internet can be extremely useful. There are several sites that give regularly updated satellite images, examples of which include http://www.sat24.com for Europe and Africa or http://www.intellicast.com/National/Satellite for US images. Try out the ‘Pan and Zoom’ feature! Particularly useful are the infrared images, as they can be seen at night.

If your telescope is stored in a garage, then setting it up before you go inside after arriving home from work is a great way of maximizing observation time. Your telescope is already cooling down to ambient temperatures while you are greeting the family or loved ones after a hard day’s work. This is a particularly useful timesaver for cooling the optics of a large SCT, which can take up to two hours.

What about storing the telescope outside? By this we don’t for a minute mean that you should leave your pride and joy nicely set up in the middle of the garden in all kinds of weather and, indeed where someone might be tempted to relieve you of it in your absence. No. By storing outside we only

mean to store it outside the house or your apartment, preferably in a secure shed or garage. As these are not, usually, heated, storing your telescope thus will dramatically reduce the amount of time you will spend waiting for the optics to cool down to ambient temperatures outdoors.

An observatory is the ultimate in time saving. That small dome or, indeed, roll-off roof shed at the bottom of the garden is a fantastic place to retreat to after a hard day’s work. Open the roof, flick the switches, and off you go! With this setup, you have very little waiting time for your telescope’s optics

to cool. If the clouds roll in and rain threatens, you just close the roof. You can even treat yourself to a ‘quick astro-fix’ if there is a brief gap in the clouds after dinner. Of course, building and maintaining the ‘obsy,’ as it is affectionately known, is another matter and will require a little DIY skill, unless you have a large cash reserve. However, there are less expensive alternatives, especially for those of us whose gardens are little bigger than a postage stamp!

New Binocular Comet in the Morning Sky

noreply@blogger.com (Unknown) — Sat, 6 Nov 2010 18:51:00 +0200

This is an AstroAlert from Sky & Telescope.

Two observers in Japan have independently discovered an 8th-magnitude comet, low in the eastern sky just before dawn. Kaoru Ikeya spotted the comet with his 25-cm (10-inch) reflector at 39x, while Shigeki Murakami used a 46-cm (18-inch) reflector at 78x, as reported in IAU Circular 9175 of November 3rd from the Central Bureau for Astronomical Telegrams (CBAT),.

What's astonishing is that both Ikeya and Murakami did it the old-fashioned way: by looking into the eyepiece of a telescope! Visual comet discoveries have become a rarity in this age of powerful professional surveys and digital imaging techniques.
Brian G. Marsden (Minor Planet Center) has calculated a preliminary orbit for the comet, designated C/2010 V1. It is moving in a parabolic orbit and is just past perihelion at 1.7 astronomical units from the Sun (that is, well outside the orbit of Mars). So while this comet won't be getting any brighter in the coming weeks, it should stay within reach of binoculars as it moves slowly southeastward across Virgo.
On November 4th, J. J. Gonzales in Spain and Carl Hergenrother in Arizona called it roughly magnitude 7.5 in their binoculars, while Alan Hale in New Mexico put it at 9.0. To all three observers, it resembled a fuzzy round glow with no tail.

Working remotely from Italy, Ernesto Guido and Giovanni Sostero used a Global-Rent-a-Scope (GRAS) telescope in New Mexico for this confirming image of the new comet.

Ernesto Guido and Giovanni Sostero

The following ephemeris gives the comet's coordinates (equinox 2000.0) at 0 hours Universal Time on selected dates, aling with its angular elongation from the Sun.

Comet Ikeya-Murakami
Date 2010	R. A. ^h ^m	Dec. ° '	Elong. °
Nov. 5	12 38.0	-02 26	32.6
Nov. 7	12 43.1	-03 06	33.2
Nov. 9	12 48.2	-03 47	33.8
Nov. 11	12 53.3	-04 27	34.4
Nov. 13	12 58.3	-05 06	35.0
Nov. 15	13 03.4	-05 46	35.6

Be sure to check the online version of this AstroAlert on Sky & Telescope's website for updates when the orbit is improved: