Posted on 03/01/2005 9:32:59 PM PST by NormsRevenge
LOS ANGELES (AP) - NASA scientists used an infrared telescope to see past stardust and spot hidden galaxies more than 11 billion light-years from the Earth, according to a journal article published Tuesday.
Scientists used the Spitzer Space Telescope to find the galaxies, the most luminous in the universe. The galaxies shine with light equivalent to 10 trillion suns but were too far away and too drenched in cosmic dust to be seen - until now.
"We are seeing galaxies that are essentially invisible," said Professor Dan Weedman of Cornell University, in Ithaca, N.Y.
Weedman co-authored an article detailing the discovery in the latest issue of Astrophysical Journal Letters.
"Past infrared missions hinted at the presence of similarly dusty galaxies over 20 years ago, but those galaxies were closer. We had to wait for Spitzer to peer far enough into the distant universe to find these," he said.
Spitzer, a $670 million mission launched in August 2003, is managed by NASA's Jet Propulsion Laboratory in Pasadena. Science operations are conducted by the Spitzer Science Center at the California Institute of Technology.
There are still many unanswered questions.
Astronomers say the galaxies' brightness may stem from a new breed of quasars, which are powered by giant black holes, but scientists are unsure where all the dust comes from. They know stars churn it out, but they are trying to find out how the cosmic dust gets stirred through the galaxies.
They also want to know if galaxies like these will eventually grow as dim as the Milky Way.
"It's possible stars like our sun grew up in dustier, brighter neighborhoods, but we really don't know. By studying these galaxies, we'll get a better idea of our own galaxy's history," said Professor James Houck, also of Cornell, and lead author of the study.
The Cornell-led team identified 31 galaxies that can only be seen with the aid of Spitzer. The team also found that more than half of the galaxies have dust grain known as silicate, which helped astronomers determine how far away the galaxies are from Earth.
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On the Web: http://www.spitzer.caltech.edu
This artist's conception shows what a dusty and bright galaxy located billions of light-years away might look like close up if viewed in infrared light. Galaxies like these are so far away and so drenched in dust, they appear invisible to optical telescopes.
NASA's Spitzer Space Telescope uncovered a hidden population of dusty galaxies like these using its heat-seeking infrared eyes. The galaxies are among the brightest in the universe and are located 11 billion light-years away back to a time when the universe was 3 billion years old. The universe is currently believed to be 13.5 billion years old.
Astronomers are not sure what is lighting up these cosmic behemoths, but they speculate that quasars -- the most luminous objects in the universe -- may be lurking inside.
Ping!
psst!
And yet they can't find Jimmy Hoffa....
Pretty spectacular artiste conception there. What a wonderful world we live in that we have such great minds around. I am constantly amazed at our species to be able to do something positive for the human race. These guys are wonderful, the Oscar belongs to this sort of human being, if you ask me.
bttt
Dear Mr. Spitzer,
Are you Dr. Evil? You seem to be attempting to take over the world without having been asked and anti-trusting the profitable insurance and investment market? Beware.
Mojo Man
Not at the moment, but there aer some folks I can ask. :-)
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