Word: light
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Dates: during 2000-2000
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That's not all. While each of these instruments trumps the Hale in light-gathering power, many are poised to outshine even the Hubble Space Telescope, which has been delivering astonishing snapshots of deepest space since it was refurbished in 1993. The orbiting observatory's nearly 2.5-m (8-ft.) mirror isn't all that powerful, but since it floats above Earth's constantly roiling atmosphere, the Hubble has been unrivaled in the sharpness of its images. No more. Using an ingenious technological trick to eliminate atmospheric blur, most of the new telescopes will soon achieve Hubble-quality focus...
...also been a long time coming. Impressive as the Hale telescope was for its day, it represented a technological dead end. The Hale, like its smaller predecessors, was powered by a mirror that's essentially a huge hockey puck of glass ground into a concave, light-focusing curve on one face and coated with reflective metal. To keep from sagging under its own weight and distorting the curve, the mirror had to be a bulky 26 in. thick, and it weighed 20 tons. That enormous heft called for an even more massive support structure to hold the whole thing...
During the 1960s, astronomers' lust for light was temporarily satisfied by the development of electronic light detectors. Because these detectors are up to 100 times as sensitive as photographic plates--the standard recording medium since the turn of the 20th century--every telescope on Earth saw its power boosted a hundredfold essentially overnight. That kept the scientists happy only for a while, however, and everyone agreed that telescopes needed some sort of radical new design. Unfortunately, says Matt Mountain, director of the Gemini Observatory, "nobody knew how to make the conceptual leap...
...right. The Hubble's forte is taking brilliantly sharp pictures. But the real meat of astronomical discovery comes not so much in pretty photos of celestial objects but in the detailed analysis of their light. By smearing that light into a spectrum--the rainbow of its component colors--scientists can identify the chemical makeup of a star or galaxy, how far away it is and how fast it's rotating, among other data. If the image of a star is going to be smeared anyway, sharp pictures don't matter much, so ground-based telescopes are at no disadvantage...
George Djorgovski is using the Keck as well, but where Marcy's quarries are no more than 200 light-years way, Djorgovski's are closer to 10 billion. A professor at Caltech, Djorgovski has lately been concentrating on gamma-ray bursts--mysterious flashes of high-energy radiation that have baffled astronomers for nearly 40 years. If these blips of electromagnetic energy can be seen from far across the universe, as some astronomers believe, then they must briefly shine as bright as the rest of the stars in the universe put together--a seemingly preposterous assertion...