For the past two years, the United Kingdom Infra-Red Telescope in Hawaii has been scanning the heavens in the faint infrared region of the spectrum. It's the widest-ever infrared glimpse of the sky.
The new technology allows astronomers to penetrate dark clouds that hide star birth and to uncover stars much less massive and much cooler than our sun.
Our own Milky Way galaxy is transparent at infrared wavelengths, so infrared telescopes can see through to its core.
Finally, the movement of the expanding universe turns visible light from the youngest and most distant galaxies and quasars into infrared radiation. So with infrared telescopes, the youngest objects come into focus.
Warren said the infrared survey promises to yield many "serendipitous" discoveries. Already, it's revealed a brown dwarf—or very cool, low-mass star—100 degrees Celsius (180 degrees Fahrenheit) cooler than the previous record holder.
Called ULAS J0034, the star has an absolute temperature just over twice that of the Earth.
Parting the Curtains
Warren said the goal of the infrared work is to examine nearly the whole sky at the same resolution that revealed the brown dwarf. It's an ambitious project, with data releases planned every six months for the next five years.
Currently, studies of the visible universe—such as most of those made with the Hubble telescope—rule the day, having shown more about the universe than any other method.
But that may soon change.
"By 2012 we'll have detected a hundred million galaxies" using infrared methods, Warren said.
Another survey called the Sloan Digital Sky Survey, run by a team of astronomers from a wide consortium of universities and observatories, is using x-ray vision to cut through the glare of quasars—extremely bright, starlike objects—that have dominated many celestial views.
The team has found that very luminous quasars—the brightest of which outshine the Milky Way by more than a hundred times—have been stealing the show from dimmer quasars and from black holes.
It turns out that these hidden quasars make up at least half the quasars in the recent universe—and that most of the powerful black holes in our universal neighborhood have gone unseen.
With all the new surveys comes new territory for scientific study, said Shardha Jogee, who presented the study about the universe's midlife slowdown.
For example, there's a huge gap in the evolution of the universe that is yet to be described: "the gas component. We are tracing the stars, the dust even the dark matter. But the gas we don't have, and it's the gas from which you make stars," she said.
"It may be a quiet time for galaxies, but I don't think it's going to be a quiet time for astronomers."
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