A Noble 'QUEST'
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What do you do when that old telescope of yours has seen its day? Throw it away? Barter over it in a garage sale? Convert it into a new water heater? May it never be! You breathe into it the breath of new life and turn it into the world's largest astronomical camera.
And that's precisely what a team of astrophysicists from Caltech, Yale University, the Jet Propulsion Laboratory, and Indiana University has done with the 56-year-old Oschin Telescope on nearby Palomar Mountain.
Built at the same time as the famous 200-inch Hale Telescope, the 48-inch Samuel Oschin Telescope saw first light in 1948 and has been a sturdy workhorse for more than half a century, scanning the heavens in various sky surveys.
But now a group of astronomers has made it even better by hooking up to it a kind of super science surveillance camera that can study the universe from our solar system all the way out to the farthest reaches of space --- over 10 billion light years away.
Called QUEST (Quasar Equatorial Survey Team), this Mother of All Digital Cameras is a masterful coordination of 112 charged-coupled devices (CCDs), the same critters capturing images inside digital cameras nowadays. But this camera is bigger --- a whole lot bigger.
But why not use Palomar's legendary 200-inch Hale telescope to do this? A 200-inch mirror can pick up a whole lot more light than one just 48 inches across. Scott Kardel, Palomar Public Affairs Director explains, "Yes, the 200-inch can see deeper, but the 48-inch can see a field of view that is more than 31 times wider, about the width of your hand at arm's length. It gives astronomers a much bigger net that they can cast to find interesting things in the universe."
Oschin's wide field of view coupled with that large array of CCDs allows astronomers to collect a massive amount of data, the very lifeblood of science. How much data? Would the equivalent of about two million books per month impress you?
But wait! There's more.
The way the whole new-fangled contraption is set up allows astronomers to put together successive images of the sky and perform a little observing magic.
"Previous sky surveys provided essentially digital snapshots of the sky," says S. George Djorgovski, professor of astronomy at Caltech. "Now we are starting to make digital movies of the universe."
The Palomar-QUEST survey, as it is officially called, is like an all-sky spy movie camera on the constant lookout for all kinds of mysterious celestial objects. The enormity of its wide field array and the ability to make what are essentially motion pictures of the night sky mean that astronomers can easily pick out suspects that move clandestinely in the heavens or vary in their brightness. What sort of perpetrators might these include?
Close to home, QUEST will be used to hunt down rogue asteroids. These give themselves away by moving slowly and dimly through the background stars. Once discovered, their orbits can be plotted to determine whether or not they might be headed this way anytime soon in a collision course with our planet. Discovering these scoundrels quickly may allow us to actually do something about them before they strike.
Other astronomers will use QUEST to look for flotsam and jetsam in a distant icy swarm of objects beyond the orbit of Pluto called the Kuiper Belt. Mike Brown and Chad Trujillo of Caltech used the pre-QUEST Oschin telescope two years ago to discover Quaoar, the largest object found in our solar system since Pluto in 1930. With the newly bedecked Oschin, Brown hopes to discover in the Belt what he believes are objects the size of Mars.
The latest bombshell from the realm of astronomy is that our universe is not just expanding; it's actually speeding up as it expands. All indications are that we live in an accelerating universe. But there are a lot of unanswered question to this bizarre scientific dilemma. Acting as a sort of "first alert" system, QUEST will quickly and accurately find normal everyday exploding stars called supernovae, which are used to measure how fast we are expanding.
The most devastating explosions in the universe, gamma ray bursts, are elusive to say the least. Possibly the results of freakishly big supernova explosions called hypernovae, they are very unpredictable and last just seconds. QUEST's quick response eyes-on-the-sky will be used to find and identify the brutes.
At the near farthest reaches of space lie terrifying monsters, young galaxies possessed by supermassive black holes at their very core. These beasts, called quasars, are also on the list of QUEST's Most Wanted. QUEST will work together with the Big Scopes to help solve riddles of what happened in the infancy of our universe, shortly after the Creation Event.
Adds Scott Kardel, "George Djorgovski has been using the QUEST data as a part of the search for high red shift (very distant) quasars. The 200-inch armed with a spectrograph, is used to confirm if the objects are indeed quasars. The Keck in Hawaii is then used to take more detailed follow-up observations."
It's an elegant and mysterious universe we live in. The new Oschin Telescope/Palomar-QUEST survey should make it a little less mysterious, and prove it even more beautifully elegant than we imagined.
Mark Ritter teaches astronomy at Temecula Valley High School and can be reached at mritter@firstlightastro.com.
Posted by Administrator at 2004.02. 7 12:48 PM | Comments (0)
