Posted on by Fraser Cain

Sea Launch Prepares for DIRECTV Launch

Image credit: Sea Launch
The Sea Launch team arrived at the launch site on the equator yesterday in preparation for the launch of the DIRECTV 7S broadcast satellite for DIRECTV Inc. on Tuesday, May 4, at 5:22am PDT (12:22:00 GMT), at the opening of a two-hour launch window. All systems are proceeding on schedule.

With launch site operations now underway, the marine crew has ballasted the Odyssey Launch Platform about 65 feet to ensure stability. The Sea Launch Commander (Assembly and Command Ship), will be stationed alongside the Odyssey, throughout the weekend, frequently connected by a link bridge that enables foot traffic between the two vessels.

The team will initiate a 72-hour launch countdown on Saturday, May 1. On the day before launch, the platform will be evacuated, with all personnel safely stationed on the ship, three miles from the platform, throughout launch operations. The rocket will be rolled out of its environmentally-protected hangar and automatically erected on the launch pad at L-27 hours.

Sea Launch?s Zenit-3SL vehicle will lift the 5,483 kg (12,063 lb.) DIRECTV 7S satellite to geosynchronous transfer orbit, on its way to a final orbital position at 119 degrees West Longitude. DIRECTV 7S, the second spot beam satellite in the DIRECTV fleet, will use highly focused spot beam technology to provide DIRECTV with the capacity to deliver local channels to 42 additional markets, expanding local channel coverage to a total of 106 markets. The satellite is also capable of operating from 101 degrees West Longitude, the primary orbital slot for DIRECTV. Built by Space Systems/Loral (SS/L) at their state-of-the-art manufacturing facility in Palo Alto, Calif., the 1300-series spacecraft is one of several high capacity direct-to-home (DTH) broadcast satellites SS/L has produced for DIRECTV, the leading U.S. digital television provider.

Sea Launch will carry a live satellite feed and streaming video of the entire mission, beginning at 5:00 am PDT (12:00:00 GMT). To downlink the broadcast, transponder coordinates are posted at: www.boeing.com/nosearch/sealaunch/broadcast.html
A simultaneous webcast will be posted at:
www.sea-launch.com/current_index_webcast.html

Sea Launch Company, LLC, headquartered in Long Beach, Calif., and marketed through Boeing Launch Services ( www.boeing.com/launch ), is the world?s most reliable commercial launch services provider. With the advantage of a launch site on the Equator, the proven Zenit-3SL rocket can lift a heavier spacecraft mass or provide longer life on orbit, yielding best value plus schedule assurance. Sea Launch offers the most direct and cost-effective route to geostationary orbit. For additional information, visit the Sea Launch website at: www.sea-launch.com

Original Source: Boeing News Release

Posted on by Fraser Cain

Binary Pulsar System Confirmed

Image credit: NASA/JPL
The only known gravitationally bound pair of pulsars — extremely dense, spinning stars that beam radio waves — may be pirouetting around each other in an intricate dance.

“Pulsars are intriguing and puzzling objects. They pack as much mass as the Sun crammed into an object with a cross-sectional area about as large as Boston,” said Fredrick Jenet of NASA’s Jet Propulsion Laboratory, Pasadena, Calif. Jenet and Scott Ransom of McGill University, Montreal, Quebec, Canada, have developed a theoretical model to explain the behavior of this one-of-a-kind set of pulsars.

“The physics of radio pulsar emission has eluded researchers for more than three decades,” Jenet said. “This system may be the ‘Rosetta stone’ of radio pulsars, and this model is one step toward its translation.”

The research appears in the April 29 issue of the journal Nature. Jenet and Ransom studied the recently-discovered double pulsar system, in which two spinning pulsars orbit each other.

The discovery of the two-star system, officially named PSR J0737- 3039B, was announced in 2003 by a multinational team of researchers from Italy, Australia, the United Kingdom and the United States. Those researchers proposed that the duo contained one spinning pulsar and a neutron star. Later in 2003, scientists working at the Parkes Observatory in New South Wales, Australia, determined that both stars are actually pulsars. This discovery marked the first known example of a “binary,” or double, pulsar system. The stars are referred to as A and B.

Pulsars emit high-intensity radio radiation into a narrow beam. As the pulsar rotates, this beam moves in and out of our line of sight. Hence, we see periodic bursts of radio radiation. In this sense, a pulsar works like a lighthouse, in which the light may be on all the time, but it appears to blink on and off. Scientists were surprised to find that the B pulsar is on only at certain locations in its orbit. “It’s as though something is turning B on and off,” Jenet said.

According to Jenet and Ransom, this “something” is closely related to the radio emission beam emanating from the A pulsar. They believe that B becomes bright when it is illuminated by emission from A. Jenet and Ransom used Einstein’s Theory of General Relativity to predict the future evolution of this pulsar system. The theory implies that gravitational effects will change the emission pattern of A, which will then alter the exact orbital locations where B becomes bright.

The double pulsar system is located about 2,000 light years, or 10 million billion miles, from Earth. Jenet and Ransom based their research on observations made at the Green Bank Telescope in West Virginia.

Original Source: NASA/JPL News Release

Posted on by Fraser Cain

Wallpaper: Bug Nebula

Image credit: Hubble
The Bug Nebula, NGC 6302, is one of the brightest and most extreme planetary nebulae known. At its centre lies a superhot dying star smothered in a blanket of ?hailstones?. A new Hubble image reveals fresh detail in the wings of this ?cosmic butterfly?.

This image of the Bug Nebula, taken with the NASA/ESA Hubble Space Telescope (HST), shows impressive walls of compressed gas. A torus (?doughnut?) shaped mass of dust surrounds the inner nebula (seen at the upper right).

At the heart of the turmoil is one of the hottest stars known. Despite an extremely high temperature of at least 250 000 degrees Celsius, the star itself has never been seen, as it shines most brightly in the ultraviolet and is hidden by the blanket of dust, making it hard to observe.

Chemically, the composition of the Bug Nebula also makes it one of the more interesting objects known. Earlier observations with the European Space Agency’s Infrared Space Observatory (ISO) have shown that the dusty torus contains hydrocarbons, carbonates such as calcite, as well as water ice and iron. The presence of carbonates is interesting. In the Solar System, their presence is taken as evidence for liquid water in the past, because carbonates form when carbon dioxide dissolves in liquid water and forms sediments. But its detection in nebulae such as the Bug Nebula, where no liquid water has existed, shows that other formation processes cannot be excluded.

Albert Zijlstra from UMIST in Manchester, UK, who leads a team of astronomers probing the secrets of this extreme object, says: ?What caught our interest in NGC 6302 was the mixture of minerals and crystalline ice – hailstones frozen onto small dust grains. Very few objects have such a mixed composition.?

The dense, dark dust torus around the central star contains the bulk of the measured dust mass and is something of a mystery to astronomers. They believe the nebula was expelled around 10 000 years ago, but do not understand how it formed or how long the dust torus can survive evaporation by the very hot central star.

Original Source: ESA News Release

Posted on by Fraser Cain

NASA’s X-Prize Looking for Ideas

The NASA program that offers cash prizes for the development of new capabilities to help meet the agency’s exploration and program goals is conducting its first workshop June 15-16 at the Hilton Hotel, Washington.

Centennial Challenges is a novel program of challenges, competitions, and prizes. NASA plans to tap the innovative talents of the nation to make revolutionary, breakthrough advances to support Vision for Space Exploration and other NASA priorities.

“Centennial Challenges is a small but potentially high-leverage investment by NASA to help address some of our most difficult hurdles in research and exploration,” said NASA Administrator Sean O’Keefe. “I look forward to stimulating competitions and very innovative wins that advance the nation’s Vision for Space Exploration,” he added.

The goal of Centennial Challenges is to stimulate innovation in fundamental technologies, robotic capabilities, and very low-cost space missions by establishing prize purses for specific achievements in technical areas of interest to NASA. By making awards based on achievements, not proposals, NASA hopes to bring innovative solutions from academia, industry, and the public to bear on solar system exploration and other technical challenges.

“From 18th century seafaring, early 20th century aviation to today’s private sector space flight, prizes have played a key role in spurring new achievements in science, technology, engineering, and exploration,” said Craig Steidle, NASA’s Associate Administrator for Exploration Systems. “The Centennial Challenges Program is modeled on the successful history of past prize contests, and I am proud the Office of Exploration Systems is shepherding this path-finding program for NASA,” he added.

“This workshop will help NASA develop challenges that are of high value to the agency,” said Brant Sponberg, Centennial Challenges Program Manager. “The workshop also will provide input into what challenges NASA announces this year and next year and what the rules for those competitions will be. It should be an invigorating way to lay the groundwork for this exciting program,” he said.

NASA invites individuals and organizations interested in competing to attend the 2004 Centennial Challenges Workshop. The agenda and registration information for the workshop is available on the Internet at:

http://www.tisconferences.com/nasa_centennial/

NASA plans annual Centennial Challenges workshops. For information about the program on the Internet, visit:

centennialchallenges.nasa.gov

Original Source: NASA News Release

Posted on by Fraser Cain

Mars Express Radar Deployment Delayed

Image credit: ESA
The MARSIS team has advised ESA to delay the deployment of the MARSIS radar instrument on board Mars Express, scheduled for this week.

New and improved computer models suggest that, during deployment, the radar booms may swing back and forth with larger amplitudes than previously expected. If this happened, the booms might come too close to delicate components of the spacecraft body. Further simulations and tests are under way to better understand the situation.

The two main radar booms are 20-metre long hollow cylinders, of 2.5 centimetres diameter, folded up in a box like a concertina (accordion). When the box is opened, the elastic energy of the compressed glass-fibre booms will let them unfold like a jack-in-the-box.

After the booms spring out, they will eventually lock in a straight line, taking up the shape that they had before being folded into the box. The deployment procedure of each boom is expected to last about 10 minutes.

Simulations carried out four years ago by the radar boom’s manufacturer, Astro Aerospace, California, USA, indicated that the deployment should be smooth, without significantly swinging back and forth. However, the radar team has now advised ESA that a new and refined analysis of the boom dynamics indicates that a sort of “backlash” might take place before the boom locks into its position.

Although a successful deployment is not in question, Mars Express mission managers want to make sure that the booms are not subjected to excessive mechanical stress and that they do not interfere with the spacecraft as they deploy.

The MARSIS team and their industrial contractors are now performing further tests and simulations to confirm that the deployment will have no impact on the safety of the spacecraft. These simulations will then be reviewed by ESA’s experts. Based on the results, expected within a few weeks, ESA will decide when and how to activate MARSIS.

MARSIS will study the sub-surface of Mars to a depth of a few kilometres. The instrument’s antennas will send radio waves towards the planet and analyse how they are reflected by any surface that they encounter. In this way, MARSIS can investigate the sub-surface mineralogical composition and will reveal the presence of any underground reservoir of water or ice.

Original Source: ESA News Release

Posted on by Fraser Cain

Saturn in Full Colour

Image credit: NASA/JPL/Space Sciences
Saturn and its rings completely fill the field of view of Cassini’s narrow angle camera in this natural color image taken on March 27, 2004. This is the last single `eyeful’ of Saturn and its rings achievable with the narrow angle camera on approach to the planet. From now until orbit insertion, the rings will be larger than the camera’s field of view. The image is a composite of three exposures in red, green, and blue, taken when the spacecraft was 47.7 million kilometers (29.7 million miles) from the planet. The image scale is 286 kilometers (178 miles) per pixel.

Color variations between atmospheric bands and features in the southern hemisphere of the planet, as well as subtle color differences across Saturn’s middle B ring, are now more distinct than ever. Color variations generally imply different compositions. The nature and causes of any compositional differences in both the atmosphere and the rings are major questions to be investigated by Cassini scientists as the mission progresses.

The bright blue sliver of light in the northern hemisphere is sunlight passing through the Cassini Division in Saturn’s rings and being scattered by the cloud-free upper atmosphere.

Two faint dark spots are visible in the southern hemisphere. These spots are close to the latitude where Cassini saw two storms merging in mid-March. The fate of the storms visible here is unclear. They are getting close and will eventually merge or squeeze past each other. Further analysis of such dynamic systems in Saturn’s atmosphere will help scientists understand their origins and complex interactions.

Moons visible in this image are (clockwise from top right): Enceladus (499 kilometers, 310 miles across), Mimas (398 kilometers, 247 miles across), Tethys (1060 kilometers, 659 miles across), and Epimetheus (116 kilometers, 72 miles across). Epimetheus is dim and appears just above the left edge of the rings. Brightnesses have been exaggerated to aid visibility.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA’s Office of Space Science, Washington, D.C. The imaging team is based at the Space Science Institute, Boulder, Colorado.

For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org.

Original Source: CICLOPS News Release

Posted on by Fraser Cain

ESO Images Cosmic Collision

Image credit: ESO
Stars like our Sun are members of galaxies, and most galaxies are themselves members of clusters of galaxies. In these, they move around among each other in a mostly slow and graceful ballet. But every now and then, two or more of the members may get too close for comfort – the movements become hectic, sometimes indeed dramatic, as when galaxies end up colliding.

ESO shows an example of such a cosmic tango. This is the superb triple system NGC 6769-71, located in the southern Pavo constellation (the Peacock) at a distance of 190 million light-years.

This composite image was obtained on April 1, 2004, the day of the Fifth Anniversary of ESO’s Very Large Telescope (VLT). It was taken in the imaging mode of the VIsible Multi-Object Spectrograph (VIMOS) on Melipal, one of the four 8.2-m Unit Telescopes of the VLT at the Paranal Observatory (Chile). The two upper galaxies, NGC 6769 (upper right) and NGC 6770 (upper left), are of equal brightness and size, while NGC 6771 (below) is about half as bright and slightly smaller. All three galaxies possess a central bulge of similar brightness. They consist of elderly, reddish stars and that of NGC 6771 is remarkable for its “boxy” shape, a rare occurrence among galaxies.

Gravitational interaction in a small galaxy group
NGC 6769 is a spiral galaxy with very tightly wound spiral arms, while NGC 6770 has two major spiral arms, one of which is rather straight and points towards the outer disc of NGC 6769. NGC 6770 is also peculiar in that it presents two comparatively straight dark lanes and a fainter arc that curves towards the third galaxy, NGC 6771 (below). It is also obvious from this new VLT photo that stars and gas have been stripped off NGC 6769 and NGC 6770, starting to form a common envelope around them, in the shape of a Devil’s Mask. There is also a weak hint of a tenuous bridge between NGC 6769 and NGC 6771. All of these features testify to strong gravitational interaction between the three galaxies. The warped appearance of the dust lane in NGC 6771 might also be interpreted as more evidence of interactions.

Moreover, NGC 6769 and NGC 6770 are receding from us at a similar velocity of about 3800 km/s – a redshift just over 0.01 – while that of NGC 6771 is slightly larger, 4200 km/s.

A stellar baby-boom
As dramatic and destructive as this may seem, such an event is also an enrichment, a true baby-star boom. As the Phoenix reborn from its ashes, a cosmic catastrophe like this one normally results in the formation of many new stars. This is obvious from the blueish nature of the spiral arms in NGC 6769 and NGC 6770 and the presence of many sites of star forming regions.

Similarly, the spiral arms of the well-known Whirlpool galaxy (Messier 51) may have been produced by a close encounter with a second galaxy that is now located at the end of one of the spiral arms; the same may be true for the beautiful southern galaxy NGC 1232 depicted in another VLT photo (PR Photo 37d/98).

Nearer to us, a stream of hydrogen gas, similar to the one seen in ESO PR Photo 12/04, connects our Galaxy with the LMC, a relict of dramatic events in the history of our home Galaxy. And the stormy time is not yet over: now the Andromeda Galaxy, another of the Milky Way neighbours in the Local Group of Galaxies, is approaching us. Still at a distance of over 2 million light-years, calculations predict that it will collide with our galaxy in about 6,000 million years!

Original Source: ESO News Release

Posted on by Fraser Cain

Spirit Closes in on Columbia Hills

Image credit: NASA/JPL
NASA’s Mars Exploration Rover Spirit took more panoramic camera images of the “Columbia Hills” as it continued its long trek across the Gusev Crater floor. Spirit is still approximately 2 kilometers (1.2 miles) and 52 sols away from its destination at the western base of the hills.

Once Spirit reaches the base, scientists and rover controllers will re-analyze the terrain and determine whether to send the rover up the mountain. Another option will be to send Spirit south along the base where she may encounter outcrops as indicated by orbital images from the Mars Orbiter Camera on the Mars Global Surveyor spacecraft.

Finding outcrops has become a surprise target for some mission scenarios, mainly because they can represent the geological timeline of an area if exposing bedrock. Unlike other parts of the surface, bedrock shows materials not transported from somewhere else by dust and wind.

Meanwhile on the other side of the planet, the Mars Exploration Rover Opportunity has broken another mission record, this time drilling the deepest hole ground into a rock on another planet. While only 7.2-millimeter (about 0.28-inch) deep into the rock “Pilbara,” the rover’s grinding power has proven valuable to getting at least below the first weathered layer.

The now familiar “blueberries,” or spherules, are present in this rock, however, they do not appear in the same manner as other berries examined during this mission. Reminiscent of a golf tee, the blueberries sit atop a “stem,” thus making them even more of an obstacle through which to grind.

The plains appear to be uniform in character from the rover’s current position all the way to Endurance Crater. Granules of various sizes blanket the plains. Those same spherical granules fancifully called blueberries are present – some intact and some broken. Larger granules pave the surface, while smaller grains, including broken blueberries, form small dunes. Randomly distributed 1-centimeter (0.4 inch) sized pebbles make up a third type of feature on the plains. The pebbles’ composition remains to be determined.

Examination of this part of Mars by NASA’s Mars Global Surveyor orbiter revealed the presence of hematite, which led NASA to choose Meridiani Planum as Opportunity’s landing site. The rover science conducted on the plains of Meridiani Planum serves to integrate what the rovers are seeing on the ground with what orbital data have shown.

The hole left by the rock abrasion tool after two hours and 16 minutes of grinding was 7.2 millimeters (about 0.28 inches) deep and 4.5 centimeters (about 1.8 inches) in diameter. The tool swept the hole clean after grinding, leaving the ring of cuttings around the hole.

The team has developed a new approach to commanding the rock abrasion tool that allows for more aggressive grinding parameters. The tool is now programmed, in the event of a stall, to retreat from its target and attempt to grind again. This allows the grinder to essentially reset itself instead of aborting its sequence altogether and waiting for further commands from rover planners.

Original Source: Astrobiology Magazine

Posted on by Fraser Cain

Space Station Gyro Breaks Down

A gyroscope failed on board the International Space Station Wednesday evening, but NASA says that it doesn’t pose a risk to astronaut safety. The gyroscope failed only hours after the hatch was opened between the station and the Soyuz capsule carrying three astronauts. The station’s four gyroscopes are designed to keep it oriented properly in space, but it can still work with only one functioning gyro. Even if that fails, the station can use maneuvering jets on the attached Soyuz capsules for keeping position. A previous gyro broke a year ago, and it was supposed to have been repaired, but the Columbia disaster put this on hold.

Posted on by Fraser Cain

Gravity Probe B is Working Fine

Image credit: NASA
Gravity Probe B ? a NASA mission to test two predictions of Albert Einstein’s Theory of General Relativity ? is orbiting 400 miles above Earth, and all spacecraft systems are performing well. Its solar arrays are generating power, and all electrical systems are powered on. The spacecraft is communicating well with its supporting satellite relay and ground stations. Launched April 20 from Vandenberg Air Force Base, Calif., Gravity Probe B is managed by the Marshall Center.

At 9:57:24 am Pacific Daylight Time on Tuesday, April 20, 2004, the Gravity Probe B spacecraft had a picture-perfect launch from Vandenberg Air Force Base in South-central California. The Boeing Delta II rocket hit the exact center of the bull’s eye in placing the spacecraft in its target polar orbit, 400 miles above the Earth.

“The Gravity Probe B Mission Operations Team has performed very well during this critical spacecraft activation period,” said Tony Lyons, Gravity Probe B NASA Deputy Program Manager from Marshall Space Flight Center in Huntsville, Ala.

“We’re ecstatic,” said Stanford Gravity Probe B Program Manager, Gaylord Green. “We couldn’t have asked for a better or more beautiful launch-nor a more perfect orbit insertion.”

At approximately one hour eleven minutes, the spacecraft’s solar arrays deployed, and shortly thereafter, the on-board cameras treated all viewers, via NASA TV, to the extraordinary sight of the separation of the spacecraft from the second stage rocket, with a portion of the Earth illuminated in the background.

After two days in orbit, all Gravity Probe B systems are performing as planned. The solar arrays are generating power, and all electrical systems are powered on. The spacecraft is communicating well with the Tracking and Data Relay Satellite System (TDRSS) and supporting ground stations.

All four Gyro Suspension Systems have now been activated. In addition, a lift check was successfully accomplished for gyros #2 and #3. “We’ve successfully achieved the first of many upcoming steps in preparing these four gyroscopes for science data collection,” said Rob Brumley, Stanford Gravity Probe B Deputy Program Manager, Technical. “We are all extremely gratified with the initial performance of these gyroscopes in space, including the first ever levitation of a Gravity Probe B gyro on orbit.”

The spacecraft’s Attitude Control System is maintaining initial attitude control. Fine attitude control should be achieved when thruster calibrations have been completed. After that, the ultra-precise science telescope will be locked onto the Gravity Probe B guide star, IM Pegasi, to within a range of 1/100,000th of a degree.

“All of us on the GP-B team are very grateful for the tremendous support we have received from NASA, Lockheed Martin, Boeing, and many others,” said Francis Everitt, Gravity Probe B Principal Investigator at Stanford University. “We’re off to a fine start, but we now have a great sense of responsibility to make sure we do the science in the best possible way.”

The spacecraft is being controlled from the Gravity Probe B Mission Operations Center, located at Stanford University. The Initialization & Orbit Checkout (IOC) phase of the Gravity Probe B mission is planned to last 45-60 days, after which the 12-month science data collection will begin. This will be followed by a two-month final calibration of the science instrument assembly.

NASA’s Gravity Probe B mission, also known as GP-B, will use four ultra-precise gyroscopes to test Einstein’s theory that space and time are distorted by the presence of massive objects. To accomplish this, the mission will measure two factors — how space and time are warped by the presence of the Earth, and how the Earth’s rotation drags space-time around with it.

NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Gravity Probe B program for NASA’s Office of Space Science. Stanford University in Stanford, Calif., developed and built the science experiment hardware and operates the science mission for NASA. Lockheed Martin of Palo Alto, Calif., developed and built the GP-B spacecraft.

For supporting materials for this news release – such as photographs, fact sheets, video and audio files and more – please visit the NASA Marshall Center Newsroom Web site at:

Marshall Space Flight Center

Original Source: NASA News Release