Arecibo Observatory: Watching for Asteroids, Waiting for E.T.
Arecibo Observatory, which is in Puerto Rico, is the location of the world’s largest single-dish radio telescope. Because radio telescopes can work at all times of day and in all kinds of weather, the observatory operates 24 hours a day. It celebrated its 50th anniversary of work in 2013.
While the observatory does a lot of astronomy work, it is perhaps most famous for being the site of the huge Search for Extra Terrestrial Intelligence (SETI) message directed at the globular cluster M13 in 1974.
These days, Arecibo is frequently used for finding asteroids that are swinging close to Earth. The observatory focuses on those that could pose a danger to the planet, making an effort to accurately measure their sizes to gauge the potential impact it could have.
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