space

2010-05-02T00:52:00.001-07:00

Mission

2010-05-02T00:40:00.000-07:00

Mission Summary

The Advanced Composition Explorer (ACE) is an Explorer mission that was managed by the Office of Space Science Mission and Payload Development Division of the National Aeronautics and Space Administration (NASA). More on the ACE personnel, including scientific Co-Investigators can be found here.
ACE launched on a McDonnell-Douglas Delta II 7920 launch vehicle on August 25, 1997 from the Kennedy Space Center in Florida.
The Earth is constantly bombarded with a stream of accelerated particles arriving not only from the Sun, but also from interstellar and galactic sources. Study of these energetic particles contributes to our understanding of the formation and evolution of the solar system as well as the astrophysical processes involved. The Advanced Composition Explorer (ACE) spacecraft carrying six high-resolution sensors and three monitoring instruments samples low-energy particles of solar origin and high-energy galactic particles with a collecting power 10 to 1000 times greater than past experiments.
ACE orbits the L1 libration point which is a point of Earth-Sun gravitational equilibrium about 1.5 million km from Earth and 148.5 million km from the Sun. From its location at L1 ACE has a prime view of the solar wind, interplanetary magnetic field and higher energy particles accelerated by the Sun, as well as particles accelerated in the heliosphere and the galactic regions beyond.
ACE also provides near-real-time 24/7 continuous coverage of solar wind parameters and solar energetic particle intensities (space weather). When reporting space weather ACE provides an advance warning (about one hour) of geomagnetic storms that can overload power grids, disrupt communications on Earth, and present a hazard to astronauts.
The spacecraft has enough propellant on board to maintain an orbit at L1 until ~2024.
More details of the ACE mission can be found in the ACE Mission Paper, published in Space Science Reviews.

Science Goals

The prime objective of ACE is to measure and compare the composition of several samples of matter, including the solar corona, the solar wind, and other interplanetary particle populations, the local interstellar medium (ISM), and galactic matter. While there has been great progress addressing these objectives, the changing conditions over the solar cycle present new opportunities. In addition, new observations and theoretical advances, new missions, and the evolving goals of NASA and the Heliophysics Theme have introduced new challenges, including the goal of achieving the scientific understanding needed to forecast space weather in the coming years when humans will venture beyond Earth's protective magnetosphere.
The nine scientific instruments on ACE are performing:

Comprehensive and coordinated composition determinations

Elemental
Isotopic
Ionic charge state

Observations spanning broad dynamic range

Solar wind to galactic cosmic ray energies
(~100 eV/nucleon to ~500 MeV/nucleon)
Hydrogen to Zinc (Z = 1 to 30)
Solar active and solar quiet periods

Investigations of the origin and evolution of solar and galactic matter

Elemental and isotopic composition of matter
Origin of the elements and subsequent evolutionary processing
Formation of the solar corona and acceleration of the solar wind
Particle acceleration and transport in nature

Mission Status

Last update: April, 2008
ACE has been at the L1 point for over 10 years, and the spacecraft and instruments are still working very well, with the exception of the SEPICA instrument. Due to failure of the valves that control gas flow through the instrument, active control of the SEPICA proportional counter is no longer possible. At this time, we do not expect to deliver any SEPICA data beyond Feb 4 2005, unless one of the valves opens by itself, as has happened a few times in the past.
A fuel use strategy has been implemented that will allow continued operations through the year 2024 (see below).As of October 2006, 438 peer reviewed papers have been published by ACE science team members. See the ACE Publications List for more information.
Publication-quality data from the ace instruments are available on the web from the ACE Science Center.
The ACE Education and Public Outreach (E&PO) Committee, in cooperation with the cosmic ray group at NASA GSFC, has set up a page with ACE and other E&PO material on the web at: http://helios.gsfc.nasa.gov
Over 100 Science News items have been released by the ACE Science Center. You can check http://www.srl.caltech.edu/ACE/ACENews_curr.html
for the latest science news from ACE.
A Space Science Reviews book that contains all the ACE instrument papers has been published (vol. 86, Issue 1/4, 1998).
Also, the Advanced Composition Explorer (ACE) Lessons Learned and Final Report is out and available in pdf form (4.4 MByte).
On January 21, 1998, NOAA and the ACE project opened up the ACE Real Time Solar Wind (RTSW) monitoring capability to the public. The service provides continuous coverage of the solar wind parameters and solar energetic particle intensity. ACE's position a million miles upstream of earth gives as much as an hour's warning of CME's that can cause geomagnetic storms here at earth. See http://sec.noaa.gov/ace/index.html

ACE Orbit and Fuel Use Strategy

Three types of maneuvers (attitude, orbit and spin) have been used since July 2001 to control ACE. Orbit maneuvers use 3lbm/year of fuel per year and keep the spacecraft bound to the L1 libration point. Attitude maneuvers use 6lbm/year and are required to maintain the HGA antenna constraint. With this strategy, fuel use is 9 lbm/y total, and the 154 lbm of fuel remaining as of October 2007 will be consumed by year 2024.
Initially, two Z-axis maneuvers using 16 lbm/y were used to prevent the Sun-Earth-Spacecraft (SES) angle from dropping below 4.75° due to natural evolution of the Lissajous orbit (see figure at right). This conservative Solar Exclusion Zone (SEZ) was designed to avoid solar radio interference with the downlink. As a result of discontinuing the Z-axis maneuvers after July 2001, ACE transited the SEZ with an SES angle of <2° every 3 months from September 2003 thru May 2005. Although the solar radio flux reduced the telemetry link margin to <3 dB during some of these transits, no science data were lost, as the ACE solid-state recorder has 86-hour capacity. Spacecraft commanding continued uninterrupted. Neither NASA nor NOAA has lost any data during SEZ transits, even in May 2004 when the minimum SES angle was 0.2° during a 21-hour crossing of the solar disk as viewed from Earth.
As the Lissajous orbit continues to evolve, the next SEZ transits within 2° will occur in 2011-2013 at solar maximum. Based on experience during 2003 - 2005, we expect minimal data loss at solar maximum. Should considerations warrant, it is possible to resume Z-axis maneuvers at any time prior to 2011. However, each year that the Z-axis is controlled requires an additional 16 lbm of fuel, shortening the remaining mission by 21 months.

History and Background

ACE was conceived at a meeting on June 19, 1983 at the University of Maryland. The meeting was hosted by George Gloecker and Glen Mason. The participants were Drs. L. F. Burlaga, S. M. Krimigis, R. A. Mewaldt, and E. C. Stone. This meeting had been preceded by preliminary documentation from the Johns Hopkins University Applied Physics Laboratory (APL) and the University of Maryland under the proposal name of Cosmic Composition Explorer. An unsolicited proposal was put together and forwarded to the NASA Explorer Program Office later that year, but was not acted upon.
The proposal was resurrected at the instigation of Dr. Vernon Jones and officially resubmitted to NASA in 1986 as part of the Explorer Concept Study Program. In 1988, the ACE mission was selected for a one-year "Phase A" (concept) Study. This study was a collaborative effort between spacecraft design and science teams.
The ACE Mission officially began on 22 April 1991 when the contract between NASA/GSFC and the California Institute of Technology was signed. APL, designer and builder of the ACE spacecraft, was involved in planning for Phase B (definition). The early ACE Spacecraft effort (April to July 1991) was primarily for ACE mission support, spacecraft system specification and ACE instrument support and interface definition. Phase B of the ACE mission officially began in August 1992.
The Mission Preliminary Design Review was held in November 1993. Phase C/D (implementation) began shortly thereafter.

Mission and Spacecraft Characteristics

The spacecraft is 1.6 meters across and 1 meter high, not including the four solar arrays and the magnetometer booms attached to two of the solar panels. At launch, it weighed 785 kg, which includes 189 kg of hydrazine fuel for orbit insertion and maintenance. The solar arrays generate about 500 watts of power. The spacecraft spins at 5 rpm, with the spin axis generally pointed along the Earth-sun line and most of the scientific instruments on the top (sunward) deck.

ACE launched on a McDonnell-Douglas Delta II 7920 launch vehicle on August 25, 1997 from the Kennedy Space Center in Florida.
In order to get away from the effects of the Earth's magnetic field, the ACE spacecraft has travelled almost a million miles (1.5 million km) from the Earth to the Earth-sun libration point (L1). By orbiting the L1 point, ACE stays in a relatively constant position with respect to the Earth as the Earth revolves around the sun.

Communication Subsystem: Primary Mission, S-band, DSN;
Communication Subsystem: NOAA - S-band @ NOAA Receiving Stations, TBD
Total Onboard Data Storage in Two Solid State Recorders -- 2 Gigabits
Primary Mission Downlink Rates: 78 & 6.9 kbps and 434 bps
NOAA Real Time Solar Wind Mission: 434 bps

Authors: Eric R. Christian - erc@cosmicra.gsfc.nasa.gov and Andrew J. Davis -ad@srl.caltech.edu
Some content copied from the JHU/APL ACE Page
Curators: ACE Science Center - asc@srl.caltech.eduLast Updated: April 15, 2008

Source :www.srl.caltech.edu/ACE/ace_mission.html#summary

NASA's Ambitious New Space Telescope Passes Critical Test

2010-05-02T00:22:00.000-07:00

By SPACE.com Staffposted: 01 May 2010 01:33 pm ET

NASA's hotly-anticipated new space observatory has passed its most significant mission milestone yet – a critical design review that sets the stage for a planned 2014 launch.

This means that the James Webb Space Telescope (JWST) a huge infrared telescope designed to peer farther back into the universe's history than ever before, has met all science and engineering requirements for its upcoming mission, NASA scientists said.

"I'm delighted by this news and proud of the Webb program's great technical achievements," said Eric Smith, the new telescope's program scientist at NASA Headquarters in Washington, D.C. "The independent team conducting the review confirmed [that] the designs, hardware and test plans for Webb will deliver the fantastic capabilities always envisioned for NASA's next major space observatory."

Meet the James Webb Space Telescope

The James Webb Space Telescope, pegged as the successor to the 20-year-old Hubble Space Telescope, is a next-generation space observatory for exploring deep space phenomena from distant galaxies to nearby planets and stars.

The new observatory is named after the late former NASA administrator James Webb, who led the space agency from 1961 to 1968. The telescope's entire mission, which has cost about $ 1 billion more than expected and taken a few years longer than planned, is estimated to cost about $5 billion.

But scientists have said the delays and overruns pale in comparison to the secrets of the universe the James Webb Space Telescope is expected to unlock.

The telescope is dedicated to studying the universe in infrared, rather than the optical light wavelengths dominated by Hubble. That means that while Webb telescope won't take the traditional photos Hubble has made popular, it will be able to observe older light and see deeper into the universe.

The telescope is designed to provide important clues about the formation of the universe and the evolution of our own solar system, from the first light after the Big Bang to the formation of star systems capable of supporting life on planets like Earth.

The review brought together multiple modeling and analysis tools. Because the observatory is too large for validation by actual testing, complex models are created to show how it will behave during launch and in the space environments in which it will be integrated.

These models are then evaluated against prior test and review results of the observatory's components.

More milestones ahead

The Mission Critical Design Review (MCDR) encompassed all previous design reviews, including the Integrated Science Instrument Module review in March 2009, the Optical Telescope Element review completed in October 2009, and the sun shield review completed in January 2010.

Next, the project schedule will undergo a review within the next few months. Final approval for the spacecraft design, which passed a preliminary review in 2009, is slated for next year.

"This program landmark is the capstone of seven years of intense, focused effort on the part of NASA, Northrop Grumman and our program team members," said David DiCarlo, sector vice president and general manager of Northrop Grumman Space Systems, located in Redondo Beach, Calif. "We have always had high confidence that our observatory design would meet the goals of this pioneering space mission."

While the MCDR approved the telescope design and gave the official go-ahead for manufacturing, hardware development on the mirror segments has been in progress for several years.

This month, ITT Corp. in Rochester, N.Y., demonstrated robotic mirror installation equipment designed to position segments on the backplane. The segments' position will be fine-tuned to tolerances of a fraction of the width of a human hair.

Additionally, the telescope's sun shield moved into its fabrication and testing phase earlier this year.

The three major elements of Webb – the Integrated Science Instrument Module, Optical Telescope Element and the spacecraft itself – will proceed through hardware production, assembly and testing prior to delivery for observatory integration and testing that is currently scheduled to begin in 2012.

The JWST is a joint project of NASA, the European Space Agency and the Canadian Space Agency. The mission is managed by NASA's Goddard Space Flight Center in Greenbelt, Md.

Source :www.space.com/missionlaunches/james-webb-space-telescope-critical-test-100501.html

Skywatching Highlights of 2010

2010-05-01T23:59:00.000-07:00

By Joe Rao
SPACE.com Skywatching Columnistposted: 03 January 2010
09:09 am ET

Here are some of the more noteworthy sky events that will take place in 2010. Each will be covered in greater detail as the event approaches. Notes about terminology:

Magnitude: On this scale, smaller numbers represent brighter objects, with the brightest stars and planets represented by negative numbers.

Degrees: Distances in the sky, from our point of view, are measured in degrees. Your fist on an outstretched arm measures about 10 degrees of sky.

Jan. 15 – Solar Eclipse

An annular (ring) eclipse of the sun will take place over parts of Africa, India and China. Because the moon is near apogee (its farthest point from Earth in its orbit) and the Earth has just passed perihelion. So the moon appears much smaller than average, and the sun somewhat larger than average. The moon's circle is only about 92 percent as wide as the sun; so 4 percent of the sun's width shows on each side of the moon. Thus, the annular phase lasts a maximum of 11 minutes and 8 seconds. This is a very long duration indeed: nearly twice as long as some people got to watch last July's total eclipse. According to eclipse expert Fred Espenak of NASA's Goddard Space Flight Center, this is the longest annular eclipse of the 3rd Millennium – its duration will not be exceeded until the year 3043!

Jan. 29 – Mars Close Approach

Mars will be only 61.7 million miles from Earth, closer than it will be again until March 2014. Peaking at magnitude -1.3, Mars will outshine all stars and other planets except Sirius and Jupiter. Opposition to the sun occurs on the 29th. It's during January that Mars begins to become large enough to show, through telescopes, touches of dark surface detail and perhaps occasional white clouds or limb hazes in medium-sized amateur telescopes at the best moments on steady nights when it's fairly high. With time and practice you may see even more. Despite any rumors you might hear, Mars will not be "as big as the full moon" or anywhere near that large. To the naked eye, it will remain a star-like point in the sky.

Feb. 16 – Venus and Jupiter Get Together

Like two ships passing in the twilight, Venus and Jupiter come within about 0.5-degrees of each other this evening. Jupiter is heading toward the sun, while Venus is moving away from the sun. This would normally be a very striking sight, but unfortunately, this conjunction takes place with the two planets just 9 degrees east of the sun – probably too near to it to make a definite sighting. If you would still like to give it a try, then – immediately after sunset – concentrate on that part of the sky just above and to the left of where the sun has just set. Using binoculars sweep around this part of the sky; Venus (magnitude -3.8) will be sitting just below and to the left of Jupiter (magnitude -2.0).

Mar. 28 to Apr. 12: Venus and Mercury Pair Up

The two worlds make for an attractive pair in the west-northwest sky soon after sunset. Between these two dates these two planets are within 5 degrees of each other, Venus appearing to the left and slightly above the dimmer Mercury. On April 3, they will appear closest together, just a little over 3 degrees apart.

Jun. 6: Two Pairs to See

Orange-yellow Mars slides less than a degree north of the bluish star Regulus, a pretty conjunction easily seen in the middle of the evening sky. By then, Mars will have shrunk to a tiny ochre dot even in large telescopes. Also on this night, Jupiter will engage Uranus in the first of a series of three conjunction; there have been only six such triple conjunctions between 1801 and 2200. The last was in 1983 and the next will come during 2037-38.

Jun. 26: Partial Eclipse of the Moon

This eclipse favors the Hawaiian Islands, western Alaska, Australia, New Zealand, eastern portions of Malaysia and Asia. These locations will see the upper half of the moon darkened by the Earth's umbral shadow. Across parts of the eastern U.S., some evidence of the eclipse may become evident as the lighter penumbral shadow casts a "smudge" on the moon's left edge just before moonset.

Jul. 11: Total Eclipse of the Sun

Virtually the entire path of totality falls over water. It will pass within 15 miles of Tahiti (a great cruise ship opportunity) and scores a direct hit on tiny Easter Island, famous for its strange humanoid megalithic statutes. From this speck of land in the middle of the South Pacific Ocean, the sun will be totally eclipsed for 4 minutes 45 seconds. Talk about a photo-op! The only other landfall is near the very end of the totality track, over Patagonia.

Early Aug: Planetary Trio

Mars passes less than a couple of degrees south of Saturn on Aug. 1 and Venus slides just over 3 degrees to the south nine days later; on Aug. 8, the three planets will form what Jean Meeus defines as a "trio," when three planets fit within a circle with a minimum diameter smaller than 5 degrees. These three worlds are all well out (46 to 50 degrees) from the sun but, unfortunately for the Northern Hemisphere, south of it and therefore rather low to the sunset horizon.

source : www.space.com/spacewatch/100103-night-sky-events-2010.html

Black holes

2010-04-24T12:06:00.001-07:00

Black Holes: What Are They?

Black holes are the evolutionary endpoints of stars at least 10 to 15 times as massive as the Sun. If a star that massive or larger undergoes a supernova explosion, it may leave behind a fairly massive burned out stellar remnant. With no outward forces to oppose gravitational forces, the remnant will collapse in on itself. The star eventually collapses to the point of zero volume and infinite density, creating what is known as a “singularity ". Around the singularity is a region where the force of gravity is so strong that not even light can escape. Thus, no information can reach us from this region. It is therefore called a black hole, and its surface is called the “event horizon ".

But contrary to popular myth, a black hole is not a cosmic vacuum cleaner. If our Sun was suddenly replaced with a black hole of the same mass, the Earth's orbit around the Sun would be unchanged. (Of course the Earth's temperature would change, and there would be no solar wind or solar magnetic storms affecting us.) To be "sucked" into a black hole, one has to cross inside the Schwarzschild radius. At this radius, the escape speed is equal to the speed of light, and once light passes through, even it cannot escape.

The Schwarzschild radius can be calculated using the equation for escape speed:

vesc = (2GM/R)1/2

For photons, or objects with no mass, we can substitute c (the speed of light) for Vesc and find the Schwarzschild radius, R, to be

R = 2GM/c2

If the Sun was replaced with a black hole that had the same mass as the Sun, the Schwarzschild radius would be 3 km (compared to the Sun's radius of nearly 700,000 km). Hence the Earth would have to get very close to get sucked into a black hole at the center of our Solar System.
source :
imagine.gsfc.nasa.gov/docs/science/know_l2/black_holes.html

Space Shuttle Challenger

2010-04-24T11:54:00.000-07:00

Space Shuttle Challenger (NASA Orbiter Vehicle Designation: OV-099) was NASA's second Space Shuttle orbiter to be put into service, Columbia being the first. Its maiden flight was on April 4, 1983, and it completed nine missions before breaking apart 73 seconds after the launch of its tenth mission, STS-51-L on January 28, 1986, resulting in the death of all seven crew members. The accident led to a two-and-a-half year grounding of the shuttle fleet, with missions resuming in 1988 with the launch of Space Shuttle Discovery on STS-26.Challenger itself was replaced by the Space Shuttle Endeavour, which first launched in 1992.Endeavour was constructed from spare parts originally meant for Challenger and the other shuttles in the fleet.

History

Challenger was named after two previous vessels—first, HMS Challenger, a British corvettethat, from 1872 to 1876, was the command ship for the "Challenger expedition," conducting pioneering global marine research.^[2]; and second, the Apollo 17 lunar module Challenger,which landed on the Moon in 1972.

Construction

Because of the low production of orbiters, the Space Shuttle program decided to build a vehicle as a Structural Test Article, STA-099, that could later be converted to a flight vehicle. In order to prevent damage during structural testing, qualification tests were performed to a factor of safety of 1.2 times the design limit loads. The qualification tests were used to validate computational models, and compliance with the required 1.4 factor of safety was shown by analysis.

NASA planned to refit the prototype orbiter Enterprise (OV-101), used for flight testing, as the second operational orbiter. However, design changes made during construction of the first orbiter, Columbia (OV-102), would have required extensive rework. Because STA-099's qualification testing prevented damage, NASA found that rebuilding STA-099 as OV-099 would be less expensive than refitting Enterprise.

Challenger (and the orbiters built after it) had fewer tiles in its Thermal Protection System than Columbia. Most of the tiles on the payload bay doors, upper wing surface, and rear fuselage surface were replaced with DuPont white nomex felt insulation. This modification allowed Challenger to carry 2,500 lb (1,100 kg) more payload than Columbia. Challenger was also the first orbiter to have a head-up display system for use in the descent phase of a mission

source:en.wikipedia.org/wiki/Space_Shuttle_Challenger

New Lunar Tool Invented at Glenn

2010-04-24T11:48:00.000-07:00

Researchers at NASA's Glenn Research Center have recently developed a new device that tests lunar soil strength called a vacuum bevameter. The vacuum bevameter measures the characteristics of lunar regolith simulants, or lunar soil simulants, in a vacuum chamber at specific temperatures while accounting for lunar gravity. Here, Dr. Heather Oravec, a postdoctoral researcher in the Tribology and Mechanical Components branch at Glenn, performs a bevameter test on simulated lunar regolith. This system may be used to predict strength characteristics of lunar regolith in previously unexplored regions of the moon.

This research was supported by an appointment to the NASA Postdoctoral Program at the Glenn Research Center, administered by Oak Ridge Associated Universities through a contract with NASA.

Image Credit: NASA
Michelle M. Murphy, (Wyle Information Systems LLC)

source:www.nasa.gov/centers/glenn/multimedia/imagegallery/if_59_vacuum.html#googtrans/en/ar

Navigator Technology Takes GPS to a New High

2010-04-24T10:47:00.000-07:00

GPS navigational devices are as ubiquitous as cell phones, freely used by commercial and government users alike to determine location, time, and velocity. These tools, however, are only as good as the signals they receive. Now, NASA engineers have found a way to improve the reception of those signals.

GPS, which stands for the Global Positioning System, is a satellite-based navigation system made up of a network of 24 satellites placed into orbit by the U.S. Department of Defense. GPS originally was intended for military uses, but in the 1980s, the government made the system available for civilian use. GPS systems now are available to users worldwide who need accurate positioning, navigation, and timing services.

Thanks to a team of engineers from the NASA Goddard Space Flight Center in Greenbelt, Md., spacecraft operating in weak-signal areas — such as geosynchronous orbits where communications and weather satellites typically operate — will be able to acquire and track the weak GPS signals to determine their locations, much like motorists who use GPS to determine where they are. For their work developing the Navigator GPS receiver, the Goddard team was nominated for the coveted NASA "Invention of the Year" award, a prize reserved for NASA employees who have secured patents for their inventions. An announcement is expected shortly.

Although millions of people rely on GPS receivers today for terrestrial applications, onboard GPS navigation for spaceflight operations has been much more challenging — particularly for spacecraft operating above the GPS constellation, which is about 20,200 kilometers (12,727 miles) above Earth in an area normally referred to as high-Earth orbit. That is because existing GPS receivers could not adequately pick up the GPS signal, which is transmitted toward Earth, not away from it. As a result, spacecraft above the constellation could not reliably use GPS for tracking and navigational purposes, forcing them to use more expensive ground-tracking assets.

Seeing an opportunity to help lower mission costs, the Navigator team, led by Goddard engineer Luke Winternitz, used Research and Development (R&D) funding to develop algorithms and hardware for a prototype spacecraft GPS receiver that would allow spacecraft to acquire and track weak GPS signals at an altitude of 100,000 km (62,137 miles) — well above the GPS constellation, roughly one quarter of the distance to the moon.

"The R&D investment allowed us to develop the weak-signal Navigator GPS receiver and bring it to fruition," Winternitz says. "Proof of the value of this investment lies in the explosion of flight opportunities and commercialization ventures that have followed."

Since its development, the technology has secured flight opportunities on several new missions. Navigator will serve as the primary navigation sensor on NASA’s Global Precipitation Measurement Mission (GPM), which will study global rain and snowfall when it launches in 2013.

It is considered the enabling navigation technology for another Goddard-managed project, the Magnetospheric MultiScale (MMS) mission. The mission is made up of four identically instrumented spacecraft that will fly in formation in a very high-altitude Earth orbit, while measuring the 3-D structure and dynamics of Earth’s protective magnetosphere. The mission will rely on the Navigator GPS receiver’s improved sensitivity to help the satellites maintain their precise orbital position.

The Air Force Research Laboratory (AFRL) at Kirtland Air Force Base, N.M. is planning to use a Navigator engineering test unit in its "Plug-and-Play" spacecraft, an experimental satellite that can be developed and launched within days because it uses components that hook together in a manner similar to how a computer adds drives or printers via a Universal Serial Bus interface.

The Navigator team also has delivered an engineering test unit to the next-generation weather satellite called GOES-R, which the National Oceanic and Atmospheric Administration plans to launch in 2015. The contractor developing the spacecraft may use Navigator's signal-processing design in the spacecraft’s GPS receiver.

Broad Reach Engineering, an aerospace engineering firm that operates offices in Colorado and Arizona, meanwhile, is pursuing a commercial license for the Navigator signal-processing technology. It plans to use the technology to build a GPS unit for a U.S. government program currently under development. The company also plans to use Navigator to develop other products that could be used in potential commercial satellite programs or scientific missions, says Dan Smith, a Broad Reach project manager.

And if those successes weren't enough, Navigator proved its mettle during a first-of-its-kind experiment carried out during STS-125, the Hubble Space Telescope Servicing Mission last year. While astronauts rendezvoused with and grappled the telescope, the experiment used radar measurements of GPS signals that were reflected off the Hubble to provide range estimates during docking and undocking, proving a key relative navigation sensing technology that could potentially be used in a robotic rendezvous with the Hubble in the future.

"No question. The Navigator team has experienced an incredible level of success," says John Carl Adams, an assistant chief of technology for Goddard’s Applied Engineering and Technology Directorate’s mission engineering and systems analysis division. "I attribute their accomplishment to technical know-how, but also to a healthy entrepreneurial spirit. These guys saw a need and developed a solution, which is now driving down mission costs for civilian and military space programs and extending the range of spacecraft GPS sensing to geosynchronous orbits and beyond."

More Advances Planned

The team is now looking to further improve the technology.

Winternitz and his team are developing the next-generation Navigator receiver — one that can acquire the GPS signal even if the spacecraft carrying the receiver is located at lunar distances. Such a capability would reduce mission operational costs because ground controllers could track spacecraft via GPS rather than with expensive ground stations.

"We expect that the evolution of Navigator’s capabilities will open up a host of new applications and funding sources, including exploration and high-altitude science missions," Winternitz says. "Navigator’s selling points will continue to be that it can offer better navigation performance in weak-signal and highly dynamic environments

."source :www.nasa.gov/topics/technology/features/navigator-gps.html#googtrans/en/ar

Students Bring Fresh Perspective and New Technology to Webb Telescope

2010-04-24T10:38:00.000-07:00

Deep inside Building 5 at NASA's Goddard Space Flight Center in Greenbelt, Md., graduate students are on the front lines of technology development adjusting lasers and mirrors and spending long hours at a computer terminals. University partnerships are playing key roles in developing new and innovative technologies for NASA missions while creating a pathway for future NASA scientists and engineers.

"Investments in students today help us build what comes after the Webb telescope," said Lee Feinberg, Webb telescope Optical Telescope Element Manager at NASA Goddard. "University professors serve on our advisory boards. It allows us to tap the brightest minds in the country."

Past experience bears out Feinberg's observations.

Six years ago, Matthew Bolcar was a graduate student from the University of Rochester, N.Y. when he started working at NASA Goddard. He has been exploring interesting problems and developing risk-reduction techniques related to aligning segmented mirrors on the Webb telescope.

The Webb telescope primary mirror is composed of 18 segments that will unfold to create a single 6.5-meter (21-foot) mirror system once the observatory reaches orbit and begins operations. To work properly, the mirrors must be perfectly aligned. "If there were a problem, the telescope's operators could adjust the mirrors from the ground to correct for any possible misalignments," said Bruce Dean, group leader of the Wavefront Sensing and Control (WFSC) group at NASA Goddard.

Dean's group was charged with developing the software to compute the optimum position of each of the 18 mirrors, and then adjusting and aligning them, if necessary. The work was funded by the Webb telescope technology development program and was patented by Goddard in 2009. Goddard worked together with Ball Aerospace & Technologies Corp. in 2005, to develop this flight software for the Webb Space Telescope.

In 2006-2007, a team of engineers from both Goddard and Ball Aerospace & Technologies Corp., successfully tested the WFSC algorithms on a laboratory model of the Webb Telescope, proving they are ready to work in space.

Today, Bolcar is a full-time optical engineer for the Goddard WFSC group. Currently, he is working on the Thermal InfraRed Sensor (TIRS) instrument that will fly on the Landsat Data Continuity Mission (LDCM), the next in a series of satellites that have remotely sensed Earth’s continental surfaces for more than 30 years. He's also working on an experimental instrument, called the Visible Nulling Coronagraph (VNC) that would be used for exoplanet detection.

The graduate fellowship and co-op programs give NASA time to train students for optical engineering. "It takes four to five years to really train someone in wavefront-sensing technology," Dean added.

University partnerships are a great way to get young engineers and scientists interested in NASA, Bolcar agreed. "When you're a graduate student, wherever the funding is, you are going to develop partnerships and relationships," he added. "There is a potential to go beyond graduate school. It's good for the university and its good for attracting young talent to NASA."

Alex Maldonado, a University of Arizona graduate student in optical engineering, is following in Bolcar's footsteps. He spends half his time working at Goddard as a co-op student and the other half taking classes at the university in Tucson, Ariz. When at Goddard, he researches new techniques for polishing optical lenses to prevent light scattering.

Astronomers need bigger and smoother mirrors that will collect more light to allow scientists to see faint objects farther into the distant universe. A common and effective technique for shaping optical lenses is called diamond-turning, where a diamond tip cuts away the lens material. However, this technique also introduces flaws that can deflect light. Maldonado spends much of his time designing and executing testing procedures to see if new polishing techniques reduce this effect -- efforts that will be applied to the Near Infrared Camera (NIRCam), a Webb telescope imager.

The University of Arizona is providing the Near Infrared Camera (NIRCam) to the Webb Space Telescope, an imager with a large field of view and high angular resolution. Prof. Marcia Rieke at the University is the lead for that instrument.

The James Webb Space Telescope is the next-generation premier space observatory, exploring deep space phenomena from distant galaxies to nearby planets and stars. The Webb Telescope will give scientists clues about the formation of the universe and the evolution of our own solar system, from the first light after the Big Bang to the formation of star systems capable of supporting life on planets like Earth.

"In addition to the students, we work with the professors," according to Dean. Bolcar's graduate professor, James R. Fienup, is a world-renowned expert in optics. "We asked him to help us cover high-risk areas on the Webb telescope," said Dean.

"This is a win-win for the schools and NASA," said Feinberg. "We fund their graduate students, and in return, we get really bright, fresh minds working on NASA's most challenging missions.

Expected to launch in 2014, the telescope is a joint project of NASA, the European Space Agency and the Canadian Space Agency.

For more information about the James Webb Space Telescope, visit:

http://www.jwst.nasa.gov

source :www.nasa.gov/topics/technology/features/partnerships.html#googtrans/en/ar

NASA to Launch Human-Like Robot to Join Space Station Crew

2010-04-24T10:34:00.000-07:00

NASA will launch the first human-like robot to space later this year to become a permanent resident of the International Space Station. Robonaut 2, or R2, was developed jointly by NASA and General Motors under a cooperative agreement to develop a robotic assistant that can work alongside humans, whether they are astronauts in space or workers at GM manufacturing plants on Earth.

The 300-pound R2 consists of a head and a torso with two arms and two hands. R2 will launch on space shuttle Discovery as part of the STS-133 mission planned for September. Once aboard the station, engineers will monitor how the robot operates in weightlessness.

R2 will be confined to operations in the station's Destiny laboratory. However, future enhancements and modifications may allow it to move more freely around the station's interior or outside the complex.

"This project exemplifies the promise that a future generation of robots can have both in space and on Earth, not as replacements for humans but as companions that can carry out key supporting roles," said John Olson, director of NASA's Exploration Systems Integration Office at NASA Headquarters in Washington. "The combined potential of humans and robots is a perfect example of the sum equaling more than the parts. It will allow us to go farther and achieve more than we can probably even imagine today."

The dexterous robot not only looks like a human but also is designed to work like one. With human-like hands and arms, R2 is able to use the same tools station crew members use. In the future, the greatest benefits of humanoid robots in space may be as assistants or stand-in for astronauts during spacewalks or for tasks too difficult or dangerous for humans. For now, R2 is still a prototype and does not have adequate protection needed to exist outside the space station in the extreme temperatures of space.

Testing the robot inside the station will provide an important intermediate environment. R2 will be tested in microgravity and subjected to the station's radiation and electromagnetic interference environments. The interior operations will provide performance data about how a robot may work side-by-side with astronauts. As development activities progress on the ground, station crews may be provided hardware and software to update R2 to enable it to do new tasks.

R2 is undergoing extensive testing in preparation for its flight. Vibration, vacuum and radiation testing along with other procedures being conducted on R2 also benefit the team at GM. The automaker plans to use technologies from R2 in future advanced vehicle safety systems and manufacturing plant applications.

"The extreme levels of testing R2 has undergone as it prepares to venture to the International Space Station are on par with the validation our vehicles and components go through on the path to production," said Alan Taub, vice president of GM's global research and development. "The work done by GM and NASA engineers also will help us validate manufacturing technologies that will improve the health and safety of our GM team members at our manufacturing plants throughout the world. Partnerships between organizations such as GM and NASA help ensure space exploration, road travel and manufacturing can become even safer in the future."

source:www.nasa.gov/topics/technology/features/robonaut.html#googtrans/en/ar

NASA Scientists Monitor Ocean Temperatures to Understand Weather

2010-04-24T10:30:00.000-07:00

Earth's oceans and atmosphere are engaged in a complex dance, continually exchanging heat and moisture. Ocean conditions directly influence the conditions of the atmosphere. To predict our weather, forecasters need the best information they can get about the state of affairs in the sea. That's where the Short-term Prediction Research and Transition, or SPoRT, project at the Marshall Space Flight Center steps in. The SPoRT team uses NASA Earth observation satellite sensors to provide ocean temperature updates to the National Weather Service four times daily. The SPoRT scientists recently enhanced their ability to detect changes in sea surface temperatures -- a variable that greatly affects weather in coastal regions -- and the public will benefit.

The SPoRT project is expanding its reach too. The previous sea surface temperature product covered the Gulf of Mexico and the southern and eastern coastlines of the U.S. The new coverage region will include all of the ocean areas surrounding North America, from the Hawaiian Islands to the middle of the Atlantic, and from Hudson's Bay and the Gulf of Alaska to the equator, including the tropical oceans where hurricanes form.

"Our enhanced sea surface temperature product brings in more data, allowing more up-to-date and accurate inputs into weather forecasts," explains Dr. Gary Jedlovec, satellite meteorologist and SPoRT principal investigator. "We're also expanding the coverage area, benefiting more communities along the coastal regions."

"Much of the energy for weather systems comes from the ocean," adds Frank LaFontaine, a SPoRT meteorologist. "That's why the sea surface temperature is so critical to forecasters. Many storm systems like to form and/or intensify over warm water, where there's a lot of potential energy for them to tap."

LaFontaine says that the new product will help even help researchers detect thermal currents and eddies, which are important because clouds tend to form along those lines.

"For instance, tropical depressions often start forming out at sea and strengthen over the warm tropical waters," explains LaFontaine. "Variations in sea surface temperatures in coastal regions can further strengthen or weaken the storm as it makes landfall."

The SPoRT team says the data provided by their new product could help forecasters predict how intense hurricanes or tropical storms will be.

"A hurricane can ramp up offshore in intensity level so quickly, there's not enough time to warn the public," says LaFontaine. "Our product could help with predicting that intensity surge."

The enhanced product achieves its improved level of detail by adding microwave readings from the Advanced Microwave Scanning Radiometer, or AMSR, a sensor aboard NASA's Aqua satellite, to the data already in use by the previous version of the SPoRT product. That version incorporated only infrared data from the MODerate-resolution Infrared Spectrometer, also known as MODIS, aboard the Aqua and Terra satellites. The microwave data complements the infrared data in an important way.

"Microwaves can penetrate the clouds, allowing us to take data over both clear and cloudy areas," says Jedlovec. "The old version of our product left gaps where the clouds were."

The data allows the scientists to resolve small changes in the temperatures at the ocean's surface at 1-kilometer, or 0.62 mile, intervals. To put it simply, if the water temperature varies 0.2 degrees Celsius, or 0.36 Fahrenheit, between a 1 kilometer square area and the next, they can detect that difference. This level of detail improves the models used to predict weather.

Kim Newton, 256-544-0034
Marshall Space Flight Center, Huntsville, Ala.
Kimberly.D.Newton@nasa.gov

source:www.nasa.gov/topics/earth/features/sport.html

Puerto Rico and Germany Sport Fastest Buggies in NASA's 17th Annual Great Moonbuggy Race04.12.10

2010-04-24T10:27:00.000-07:00

Through flips and spills over a simulated moon surface, two veteran contenders finally found their time to shine in NASA’s 17th annual Great Moonbuggy Race. The team representing the International Space Education Institute of Leipzig, Germany, won the high school division; and racers from the University of Puerto Rico in Humacao took first place in the college division.

The teams bested more than 70 teams from 18 states, Puerto Rico, Canada, Germany, India and Romania. More than 600 drivers, engineers and mechanics -- all students -- gathered with their team advisors and cheering sections to take part in the matchup of wits and wheels at the U.S. Space & Rocket Center April 9-10 in Huntsville, Ala.

The race is organized by NASA's Marshall Space Flight Center in Huntsville. It challenges students to design, build and race lightweight, human-powered buggies that tackle many of the same engineering challenges dealt with by Apollo-era lunar rover developers at the Marshall Center in the late 1960s.

The International Space Education Institute, known among moonbuggy racers as "Team Germany," has been a prominent contender in the competition since they debuted in 2007 as the German Space Education Institute. Their team this year included two Russian students, reflecting the school's expanded international scope.

The University of Puerto Rico in Humacao -- the only school in the world to enter a moonbuggy in every race since the event was founded in 1994 -- won the second-place prize in 2009, and finally took home first place in this, their 17th appearance.

The winning teams posted the fastest vehicle assembly and race times in their divisions and received the fewest on-course penalties. The International Space Education Institute finished the roughly half-mile course -- twisting curves, treacherous gravel pits and other obstacles simulating lunar surface conditions -- in just 3 minutes 37 seconds. The University of Puerto Rico at Humacao posted a time of 4 minutes 18 seconds.

source: www.nasa.gov/topics/moonmars/moonbuggy2010/winning_teams_2010.html

No Peep from Phoenix in Third Odyssey Listening Stint

2010-04-24T10:24:00.000-07:00

Mars Odyssey and Phoenix Status Report

PASADENA, Calif. -- NASA's Mars Odyssey orbiter heard no signal from the Phoenix Mars Lander when it listened from orbit while passing over Phoenix 60 times last week.

Odyssey had also listened for a signal from Phoenix during periods in January and February. During the third campaign, April 5 through April 9, the sun stayed above the horizon continuously at the arctic site where Phoenix completed its mission in 2008.

The solar-powered lander examined ice, soil and atmosphere at the site for two months longer than its planned three-month mission before succumbing to seasonal decline in sunlight. It was not designed to withstand winter conditions. However, in case it did, NASA has used Odyssey to listen for the signals that Phoenix would have transmitted if abundant spring sunshine revived the lander.

"In the unlikely event that Phoenix had survived the harsh Martian arctic winter and been able to achieve a power-positive state with the return of continuous sunshine, there is a very high likelihood that one or more of these 60 overflights would have overlapped with a transmission attempt by the lander," said Chad Edwards, chief telecommunications engineer for the Mars Exploration Program at NASA's Jet Propulsion Laboratory, Pasadena, Calif.

"This was the last of our three planned Phoenix search campaigns. The Mars program will evaluate the results in hand to assess whether further action is warranted," Edwards said.

Media contact: Guy Webster 818-354-6278
Jet Propulsion Laboratory, Pasadena, Calif.
guy.webster@jpl.nasa.gov

2010-126

source :www.nasa.gov/mission_pages/phoenix/news/phx20100413.html

Space Shuttle Atlantis Moves to Launch Pad for Final Planned Flight

2010-04-24T10:17:00.000-07:00

posted: 22 April 2010
05:15 pm ET

CAPE CANAVERAL, Fla. — Space shuttle Atlantis held the spotlight late on Wednesday night into early Thursday morning as it rolled out of Kennedy Space Center's Vehicle Assembly Building (VAB) in Florida, on its way to the launch pad for what is planned to be its last flight.

The black-and-white winged-orbiter, mounted to an orange external fuel tank and twin white solid rocket boosters, left the voluminous building— the largest one-story building in the world — just before midnight atop a mobile launcher platform and crawler transporter tracked vehicle.

Atlantis' trip to the launch pad came just a day after the successful landing of its sister ship Discovery on Tuesday to wrap up a 15-day flight to the International Space Station.

"One of my favorite shots, almost as fantastic as launch, is coming out here in the middle of the night, watching it clear the VAB doors. When it moves out into the xenon lights and they're shining on it, there's just something very special about that," former astronaut and Kennedy Space Center director Bob Cabana told collectSPACE.com. "The beginning of this journey into space, it all starts when the whole stack rolls out."

Atlantis' first moves at 11:31 p.m. EDT Wednesday were also slated to be among its last.

source:www.space.com/missionlaunches/shuttle-atlantis-final-launch-pad-trip-cs-100422.html#googtrans/en/ar

Why Are Space Telescopes Better Than Earth-Based Telescopes?

2010-04-24T10:07:00.000-07:00

By Remy Melina Staff Writer posted: 24 April 2010 03:31 am ET

The Hubble Space Telescope has beamed hundreds of thousands of images back to Earth over the past two decades. One might call it the most skilled paparazzo, snapping countless images of the stars.

Thanks to these images, scientists have been able to determine the age of the universe and shed light on the existence of dark energy. These extraordinary advancements have been possible because the Hubble images surpass those taken by Earth-based telescopes.

While ground-based observatories are usually located in highly elevated areas with minimal light pollution, they must contend with atmospheric turbulence, which limits the sharpness of images taken from this vantage point. (The effects of atmospheric turbulence are clear to anyone looking at the stars – this is why they appear to twinkle.)

In space, however, telescopes are able to get a clearer shot of everything from exploding stars to other galaxies.

Another disadvantage for ground-based telescopes is that the Earth's atmosphere absorbs much of the infrared and ultraviolet light that passes through it. Space telescopes can detect these waves.

Newer ground-based telescopes are using technological advances such as adaptive optics to try to correct or limit atmospheric distortion, but there's no way to see the wavelengths that the atmosphere blocks from reaching Earth, according to the Space Telescope Science Institute (STScI), which manages the Hubble research program.

One downside to space telescopes like the Hubble is that they are extremely difficult tomaintain and upgrade. The Hubble is the first telescope specifically designed to be repaired in space by astronauts, while other space telescopes cannot be serviced at all.

NASA scientists estimate that the telescope will only be able to keep taking pictures for five more years.

source :www.space.com/scienceastronomy/why-space-telescopes-are-better-100424.html

Hubble Telescope Spies Majestic Space Mountains

2010-04-24T03:53:00.000-07:00

By SPACE.com Staff posted: 23 April 2010 02:42 pm ET

The prolific Hubble Space Telescope will hit an important milestone this weekend – the 20th anniversary of its launch. Hubble scientists are celebrating the iconic space telescope's milestone with a stunning new photo of pillar-like mountains of dust in a well-known nebula.

The stunning Hubble photo shows just a small part of the Carina Nebula, one of the largest seen star-birth regions in our galaxy. It captures the top of a 3 light-year-tall pillar of gas and dust that is being eaten away by the brilliant light from nearby bright stars.

The pillar is also being pushed apart from within, as infant stars buried inside emit jets of gas that can be seen streaming from the towering peaks.

source :www.space.com/scienceastronomy/why-space-telescopes-are-better-100424.html