Plan to build giant liquid telescope on Moon

Even by astronomical standards, Roger Angel thinks big. Angel, a leading astronomer at the University of Arizona, is proposing an enormous liquid-mirror telescope on the moon that could be hundreds of times more sensitive than the Hubble Space Telescope.Using a rotating dish of reflective liquid as its primary mirror, Angel's telescope would the largest ever built, and would permit astronomers to study the oldest and most distant objects in the universe, including the very first stars."It's an idea that's been around, and we decided to flesh it out," Angel says.Angel, a member of the National Academy of Sciences, a MacArthur Fellow and a Fellow of the Royal Society, is currently concluding a study to determine the feasibility of constructing a lunar liquid mirror telescope, or LMT, for NASA Institute for Advanced Concepts, an NASA-funded space think tank.LMT's have been built on Earth -- the Large Zenith Telescope in British Columbia is the third largest telescope in North America -- but the moon's low gravity and lack of atmosphere would allow for a truly gigantic instrument.

Angel dreams of a 100-meter mirror, which would be larger than two side-by-side football fields and would collect 1,736 times more light than the Hubble.Even a 20-meter instrument, which is more likely in the near term, would be 70 times more sensitive than the Hubble and could detect objects 100 times fainter than those that will be seen with the James Webb Space Telescope, a next-generation orbiting observatory scheduled for launch in 2013."At first, it sort of sounds like a crazy idea," says Paul Hickson of the University of British Columbia, one of two Canadian LMT experts who collaborated with Angel on the study. "But when you go through it in some detail, you realize it could actually work."NIAC director Bob Cassanova agrees. "It's quite feasible," he says. "The debate about this is about some of the details."