Once upon a time, shiny surfaces and mirrors were credited with magical powers that could look into the future. Now two centuries later, NASA is relying on them to look into the past.
The agency is developing a primary mirror 21.3 feet across, for use on the James Webb Space Telescope, to tell us about our beginning in the universe.
The primary mirror will serve as the telescope's eye and peer through dusty clouds to see stars forming planetary systems, connecting the Milky Way to our own solar system.
Handling delicate space hardware holds no superstitious myths for NASA, but it's still a delicate task that requires careful preparation.
On Friday, six of the 18 Webb telescope mirror segments will be moved into the X-ray and Cryogenic Facility, or XRCF, at NASA's Marshall Space Flight Centre in Huntsville, to experience mercury dipping to minus 414 degrees F to ensure they can withstand the extreme space environments.
When the primary mirror is assembled in space, it will include three different shapes of mirror segments: 6 are "A" segments, 6 are "B" segments and 6 are "C" segments.
This upcoming test in the XRCF will collect data from all three sizes "A, B and C" -- a first for these in the cryogenic facility.
This test will also include the engineering development unit, the first primary mirror segment of the Webb telescope that has met flight specifications at ambient temperatures.
"By the time testing in the XRCF concludes in 2011, all 18 flight segments will have been through multiple measurements while experiencing the extreme temperatures of space," said Helen J. Cole, James Webb Project Manager at NASA-Marshall.
"This process has been six years in the making and we're excited that we can support the Webb telescope development with our world class cryogenic test facility," Cole added, according to a NASA release
Marshall's X-ray and Cryogenic Facility is the world's largest X-ray telescope test facility and a unique, cryogenic, clean room optical test location.
Saturday, January 9, 2010
NASA develops mirror to look into galactic past
Wednesday, January 6, 2010
NASA's Kepler finds five planets
Nasa's Kepler Space Telescope has detected its first five exoplanets, or planets beyond our Solar System. The observatory, which was launched last year to find other Earths, made the discoveries in its first few weeks of science operations. Although the new worlds are all bigger than our Neptune, the US space agency says the haul shows the telescope is working well and is very sensitive. The exoplanets have been given the names Kepler 4b, 5b, 6b, 7b and 8b. They were announced at an American Astronomical Society meeting in Washington DC.
Friday, October 9, 2009
NASA to bomb Moon in search for water
Just weeks after ISRO and NASA announced discovery of evidence of water on the lunar surface, the US Space agency is all set to bomb the Moon tomorrow in search for hidden water in a controversial mission.
Scientists will see two spacecraft slamming into the moon's south pole at 9,000 kmph kicking up a 10-km-high shower of debris that National Aeronautics and Space Administration (NASA) hopes will confirm the presence of enough water necessary to supply future visits by astronauts.
Amateur astronomers in parts of the world may be able to view the impact through a telescope; for everyone else, the crash will be broadcast live on the NASA website along with early pictures of the lunar dust cloud during the dramatic mission. Within an hour of the impact, scientists will know whether water was hiding there or not.
The Indian Space Research Organisation(ISRO) announced last month that the country's first unmanned lunar mission Chandrayaan-I found evidence of water on the moon within a month after it was launched in October last year to make the first such discovery. NASA had also announced last month that it found evidence of water.
The crashing spaceship was launched in June along with an orbiter that is now mapping the lunar surface. LCROSS, short for Lunar Crater Observation and Sensing Satellite and pronounced L-Cross, is on a collision course with the moon, attached to an empty 2.2-tonne rocket that helped get the probe off the ground.
NASA is carrying out this mission to see if any water, ice or vapour is revealed in the cloud of debris. Discovering sub-surface ice is important because the ice could be used as a source of water for efforts to build a colony on the moon’s surface.
The mission itself continues to be controversial.
Questions have been raised as to whether the crash-landing on the moon was necessary for science or will it be worth the damage done to the moon. Critics say the bombing mission interferes with natural forces.
But NASA says the bombing isn’t an act of hostility and it’s all part of our search for water in space.
According to reports, the spacecraft will hit that part of the moon where scientists believe billions of tonnes of trapped ice may be held.
In the early hours of Friday(GMT) LCROSS and its empty rocket will separate. At 1131 GMT(1701) the larger empty rocket will crash into a permanently dark crater and kick up a 6.2 mile high spray of debris. Railing just behind that rocket is the LCROSS satellite itself, beaming back to Earth live pictures of the impact and the debris plume using colour cameras.
It will scour for ice, fly through the debris cloud and then just four minutes later take the fatal plunge itself, triggering a dust storm one-third the size of the first hit.
The mission is a set-the-stage venture dreamed up by the NASA office that has been working on a 75 billion dollars plan to eventually return astronauts to the moon.
The two spaceships will smash into the moon at 9,000 km per hour, more than seven times the speed of sound. The explosion will have the force of 1.5 tonnes of TNT and throw 350,000 kgs of lunar dirt out of the crater. It will create a new crater inside an old one about half the size of an Olympic swimming pool.
Friday, April 24, 2009
NASA's Spitzer Telescope casts new light on search for alien life
n the search for alien life, the big question has always been, where to look? After all, the universe is a big place.
In recent years, some experts have argued that we ought to concentrate our search on stars cooler than our sun, where it would be easier to spot nearby planets that might be suitable habitat. But new results from NASA's Spitzer Space Telescope raise questions about whether the chemistry on such planets would let life blossom.
After breaking down the light of these stars with a spectrograph, the researchers found hydrogen cyanide in 30% of the yellow, sun-like stars. They found none around cooler, smaller stars, such as M-dwarfs and brown dwarfs.
"Around cooler stars, there might not be enough hydrogen cyanide" to kick-start the complex chemical reactions necessary to form life, said Ilaria Pascucci of Johns Hopkins, lead author of the research, which is appearing this week in the Astrophysical Journal.
Most are gas giants orbiting so close to the stars that life-forms, at least the kind we know, could not gain a foothold.
In recent years, a number of scientists trying to find extraterrestrial life have suggested concentrating on relatively cool, dim stars.
This is because a key method of finding planets is to observe the dimming of a star's light caused by a planet crossing in front of it, a process known as a transit. The zone of habitability around cool stars would be close to the star, making it easier to spot transits.
In their research, the team focused on young stars from 1 million to 3 million years old, which are surrounded by what are known as "planet-forming disks" of dust and gas. These disks supply the raw material from which the planets are made.
The fact that the disks around cooler stars contain no hydrogen cyanide isn't the first evidence that those stars might not be the right place to look for planets where life can grow. M-dwarfs are prone to extreme magnetic outbursts that could interfere with developing life-forms.
"Although scientists have long been aware that the tumultuous nature of many cool stars might present a significant challenge for the development of life," said a statement by Douglas Hudgins, the Spitzer program scientist at NASA headquarters in Washington, "this result begs an even more fundamental question: Do cool stars even contain the necessary ingredients for the formation of life?"
Compounding the challenge of finding life elsewhere in the universe is the fact that we don't know for sure how life got started on our own planet.
The possibility that the recipe for life was delivered in a neat package from space is only one theory. Other theories suggest that under the right conditions, the planet itself could cook up its own stew of living organisms.
Before excluding cooler stars from the search for life, Pascucci said, she would like to do more studies of planetary disks to find out how they vary. Klik disini untuk melanjutkan »»
