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NASA has deactivated the Stardust spacecraft two weeks after it jettisoned a space capsule to Earth with the first comet dust samples.
On Sunday, engineers powered down all of Stardust’s systems except for its solar panels and receiver antenna. The move was necessary to maintain the spacecraft’s health and save fuel for possible missions in the future.
Stardust has performed flawlessly these last seven years and it jettisoned the 100-pound capsule containing microscopic debris from comet Wild 2 and interstellar dust streaming through space.
The return samples were recently flown to a laboratory at the Johnson Space Center in Houston where scientists unlocked the canister containing the particles.
A preliminary investigation revealed that the Stardust capsule trapped thousands of cosmic debris samples, exceeding scientists’ expectations. Most of the particles were tinier than the width of a human hair, but a surprising number of particles were visible to the naked eye.
The $212 million project is managed by the Jet Propulsion Laboratory in Pasadena.
On 3 February 2006, astronauts onboard the International Space Station (ISS) will hurl an empty spacesuit overboard and it will become "SuitSat", one of the strangest satellites in the history of the space age.
Unlike a normal spacewalk, with a human inside the suit, SuitSat’s temperature controls will be turned off to conserve power. The suit, arms and legs akimbo, possibly spinning, will be exposed to the fierce rays of the sun with no way to regulate its internal temperature.
Will the suit overheat? How long will the batteries last? Can we get a clear transmission if the suit tumbles? These are some of the questions SuitSat will answer, laying the groundwork for SuitSats of the future.
SuitSat is a Russian brainstorm
Astronomers on Wednesday announced the discovery of what is possibly the smallest planet known outside our solar system orbiting a normal star.
Its orbit is farther from its host star than Earth is from the sun. Most known extrasolar planets reside inside the equivalent of Mercury’s orbit. The planet and star are separated by about 2.5 astronomical units. One AU is equal to the distance between the Earth and the sun. Until now, no small planet had been found farther than 0.15 AU from its parent star.
The planet is estimated to be about 5.5 times as massive as Earth and thought to be rocky. It orbits a red dwarf star about 28,000 light-years away. Earth-sized planets have been detected, but only around dying neutron stars.
With a surface temperature of 364 degrees below zero Fahrenheit (-220 degrees Celsius), the newfound planet, named OGLE-2005-BLG-390Lb, is probably too cold to support life as we know it, astronomers said.
It was discovered using a technique called "gravitational microlensing," whereby light from a distant star is bent and magnified by the gravitational field of a foreground star. The presence of a planet around the foreground star causes light from the distant star to become momentarily brighter.
More than 9,000 pieces of space debris are orbiting the Earth, a hazard that can only be expected to get worse in the next few years, according to NASA scientists.
The pieces of space junk measuring 4 inches or more total some 5,500 tons, according to a report.
Even if space launches were halted now the collection of debris would continue growing as items already in orbit collide with one another and break into more pieces.
The most debris-crowded area is between 550 miles and 625 miles above the Earth, meaning the risk is less for manned flights. The international space station operates at about 250 miles altitude and space shuttle flights tend to range between 250 miles and 375 miles. But the growing collection of junk can pose a risk to commercial and research flights and other space activities.
Much of the debris results from explosions of satellites, especially old upper stages left in orbit with leftover fuel and high pressure fluids.
A 2004 NASA report identified Russia as the source of the largest number of debris items, closely followed by the United States. Other sources were France, China, India, Japan and the European Space Agency.
After examining stardust capsule, the scientists estimate they have up to a million comet particles, with a dozen or so that are the thickness of a human hair, and maybe even one that is larger than a millimeter. But it will take some time to know exactly what the aerogel collector tray holds.
The opposite side of the collector tray holds samples of interstellar dust. Any tracks made by these miniscule particles are not readily apparent, so it will take some time to scan the aerogel tiles and find them. The scientists estimate they have collected up to two hundred interstellar dust grains, each no larger than a micron in size.
The Johnson Space Center will be sending out Stardust samples to about 150 scientists worldwide by next week.
The New Horizons probe lifted off from the Cape Canaveral Air Force Station at 2 p.m Thursday on a 3-billion mile journey to study Pluto, the solar system’s last unexplored planet, and examine a mysterious zone of icy objects at the outer edges of the planetary system.
It was the swiftest spacecraft ever launched and was expected to reach Earth’s moon in nine hours and Jupiter in just over a year. New Horizons will reach Pluto in 2015.
Scientists announced that Stardust sample exceeds all expectations with the big ones seen from 10 feet away..
A preliminary estimation is that there might be more than a million microscopic specks of dust embedded in Stardust’s aerogel-laden collector. Furthermore, it appears — from the size of the carrot-shaped impact tracks in the aerogel — that there are about 10 particles of 100 microns in size. (A typical human hair is about 100 microns thick.)
The largest is around a millimeter, Brownlee added, and the biggest track is nearly large enough to insert your little finger. In the largest aerogel tracks, investigators can see the black comet dust at the end of the track.
The research team will spend about a week photographing the collector and examining it under a microscope before they begin the painstaking process of extracting particles, most of which are less than one-fifth the diameter of a hair.
Pluto, discovered in 1930 by the astronomer Clyde Tombaugh, turns out to be the first known example of a new class of planetary bodies called ice dwarfs — the third class of planets: where the Earth, Mercury, Venus and Mars are rocky worlds, and Jupiter, Saturn, Uranus and Neptune are gas giants The ice dwarfs are believed to be embryo planets, formed in the early days of the solar system more than four billion years ago. While other planets went on to bigger things, the ice dwarfs stopped growing.
As well as being the furthest planet from the Sun although its orbit means it is sometimes closer than Neptune — Pluto is the oddball of the solar system.
Pluto also has a less circular orbit than the other planets, it orbits around its poles instead of its equator — a characteristic it shares with Uranus — and is orbiting on a tilt of 17 degrees, more than twice as great as the next highest, Mercury, which tilts at seven degrees.
Pluto is also one of only four objects in the solar system to possess a mainly nitrogen atmosphere, the others being Saturn’s moon Titan, Neptune’s moon Triton, and the Earth. Although its surface is about minus 223 degrees Centigrade, scientists believe its interior may be warm enough to house an ocean.
The surface of Pluto is roughly minus 223 degrees Centigrade. Pressure on the surface is between three and 100 millionths that on Earth, and if you stood on Pluto you would weigh approximately seven per cent of your weight on Earth.
Pluto orbits the Sun every 248 years, and turns on its own axis once every six and a half days. During daylight on Pluto, the Sun would appear almost 300 times as bright as the full moon on Earth, but 900 times dimmer than full daylight on Earth.
Pluto’s moon Charon was discovered in 1978. Charon is more than half the size of Pluto, leading to some suggestions that they are in fact binary planets, revolving around a point between them. Two further satellites were discovered late last year. Pluto is the only planet whose rotation is synchronized with its satellite, meaning Pluto and Charon continuously face each other.
Pluto is hundreds of times fainter than can be seen with the naked eye, but can be seen with an amateur telescope — as long as you know where to look and observe the sky over several days.
Members of the public are being asked to help study cosmic dust samples returned by the Stardust space mission. The particles are buried in gel that was exposed to the interstellar dust stream during the probe’s seven-year voyage around the Solar System. Scientists need volunteers to sift through millions of pictures of the gel to locate the few dozen tiny grains.
Scientists developed the technique that the US space agency (Nasa) will use to scan the ultra-light gel (aerogel) in which the interstellar dust grains are embedded. The gel - which is contained within a "honeycomb" of collector trays - will be scanned by an automated microscope at a clean room in Nasa’s Johnston Space Center in Houston shortly after landing.
Volunteers will be able to access the images via a web-based "virtual microscope". To take part, they need a reasonably up-to-date computer with Netscape or Internet Explorer, patience and some spare time. People who register will have to go through a web-based training session to see if they are suitable.
Once located, the particles will be extracted from the gel and analysed in research labs around the world.
As well as the satisfaction of taking part in the space project, volunteers have another incentive - the chance to name any dust grains they find.
If interested, please visit
http://stardustathome.ssl.berkeley.edu/
After a seven-year, 2.9 billion-mile round trip, NASA’s Stardust space capsule floated down to a landing in the Utah desert early Sunday, bringing back interstellar dust and comet samples that scientists hope will yield clues to the origins of the solar system.
The mission came to a climax in the middle of the night, starting with the sample return capsule’s release from its mothership when it was 69,000 miles (110,000 kilometers) away from Earth. The shuttlecock-shaped capsule streaked through the atmosphere at about 29,000 mph (46,000 kilometers per hour), representing the fastest re-entry of any human-made probe.
Parachutes eased the final phase of the descent, ending with the landing at a military test range about 3:10 a.m. MT (5:10 a.m. ET). A helicopter recovery team located the capsule and would bring it to a clean room at the Utah Test and Training Range for processing. From there, it will be flown to the Johnson Space Center in Houston for analysis.
The mission marked the first time a spacecraft flew into deep space and brought back tiny fragments of a comet.
Launched in 1999, the Stardust spacecraft flew through the Wild 2 comet’s coma in 2004, a fuzzy halo of gas and dust. Outfitted with armored bumpers, the spacecraft survived a hail of debris to trap comet dust with a collector mitt packed with aerogel, a porous material made up of mostly air. The cosmic particles were then tucked inside the capsule for the trip home. Along with the comet dust, the spacecraft also captured interstellar dust — tiny particles that stream through the solar system thought to be from ancient stars that exploded and died. The spacecraft also beamed back 72 black-and-white pictures showing broad mesas, craters, pinnacles and canyons with flat floors on the surface of Wild 2, a craggy comet about 500 million miles (800 million kilometers) from Earth at Stardust’s launch.
The Stardust mothership will remain in permanent orbit around the sun.
The mission cost $212 million.
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