Google has announced Google Sky, a new feature in
Google Earth that lets you browse the entire night sky. Download the latest version of
Google Earth, and you'll find a new button on the toolbar, which switches you to the sky view.
Sky mode includes clickable layers containing the complete
Yale Bright Star Catalogue,
Messier Catalogue and Dreyer's
New General Catalogue of nebulae. Deep sky objects, such as the
Horsehead Nebula, are accompanied by handy explanatory notes from
Wikipedia. Other layers include a showcase of photos from the
Hubble Space Telescope and a tour of stellar evolution, from star formation in a molecular cloud through to death as a planetary nebula.