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The year 2009 was named The International Year of Astronomy by the International Astronomical Union (IAU) and UNESCO. It was a celebration of astronomy around the world with 141 countries taking part. "The Universe, Yours to Discover" was the official slogan. The idea was to promote astronomy worldwide and get young people interested in it. The year 2009 is special to astronomers, as it is the 400th anniversary since the first astronomical telescope by Galileo Galilei was used.

Activities run during the year included observatory tours, shows, and photograph displays. People could get involved in many of these activities online with a computer.