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The Quest To Build a Telescope On the Moon
silverjacket writes: A feature for The New Yorker describes a plan to use robots to mine lunar materials and build a radio telescope on the far side of the moon that will help answer questions about the early universe. An excerpt from the story: he dream of a lunar telescope dates to the nineteen-sixties. The moon has the advantage of being hundreds of thousands of miles away from earthly electronics; on the far side of the moon, in particular, there's virtually no noise from human technology or the Earth's magnetosphere. After the Apollo landings, however, interest in the moon waned. Jack Burns, an astrophysicist who is now at the University of Colorado Boulder, has been advocating for a moon-based telescope since 1984. "I never, never would have guessed that it would take this long," he told me. "I just won't accept no for an answer." Today, Burns is the chief scientist of FarView, as well as the primary investigator of a sort of mini-FarView: FARSIDE, which would have one or two hundred antennas instead of a hundred thousand.
If FarView is built, it would be able to detect some of the oldest light in existence. The universe began 13.8 billion years ago as a dense, fast-expanding soup of matter and energy; around three hundred and eighty thousand years later, it had cooled enough for hydrogen atoms to hold together. After that came the Cosmic Dark Ages: millions of years without stars or galaxies, a period we know very little about. But hydrogen occasionally releases light with a wavelength of twenty-one centimetres -- radio waves. Some of that light is still around.
Because twenty-one-centimetre radiation is stretched by the steady expansion of the universe -- it's now tens to hundreds of metres long -- scientists can figure out how old it is, and how far away. (The longer the wavelength, the older the light and the more distant its source.) This means that if scientists can build a radio telescope on the moon, they will be able to create a three-dimensional picture of the early universe.
Read more of this story at Slashdot.
