Astronomers all over planet Earth invite you to experience the night sky as part of the International Year of Astronomy 2009. This year was picked by the International Astronomical Union and the United Nations Educational, Scientific, and Cultural Organization because it occurs 400 years after Galileo turned one of the first telescopes toward the heavens.

As twilight sweeps around planet Earth tonight (April 4), many amateur astronomers will set up their telescopes for a 24-hour global star party. The planetwide star party is part of 100 Hours of Astronomy (100HA), a project of the International Year of Astronomy 2009.