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Google Sky is a feature for Google's Google Earth and an online sky/outer space viewer at www.google.com/sky. It shows the sky view made up of a collaboration of Hubble Telescope space photographs. It was created on August 27, 2007.
Google Earth version
The first Google Sky version to be created was on the virtual globe program called Google Earth. It features a number of layers, similar to the earth mode. It is mapped with images on the inside of the Google Earth sphere, with the north and south poles lining up with the two poles in Google Sky, it is viewed from the inside looking out from the center.  It is currently facing competition from Microsoft's WorldWide Telescope.
- Welcome to Sky: An introduction to the Sky mode.
- Current Sky Events
- Our Solar System: Shows locations, orbits and information of the Solar System.
- Backyard Astronomy: Shows information about constellations and other space sights visible from a backyard telescope.
- Featured Observatories
- Education Center
- Historical Sky Maps
- Rumsey Star Maps
- Hevelius Constellations
- Sky Community: Posted KML files in the Sky forum in the Google Earth Community.
Google also runs an internet version of Sky, which was created in response to the popularity of the Google Earth application. 
Google Sky Website was launched on March 13, 2008 as posted in Google Lat Long Blog in an article by Google Software Engineer Michael Weiss-Malik. It's accessible from any web browser and operating system and available in 26 languages (the first Google Maps product to support right-to-left languages). It was coded by Diego Gavinowich, a Latin America Code Jam finalist from Buenos Aires who joined Google for a winter internship, with the help of other engineers on their 20% time .
- Galleries highlighting
- Selected images from Hubble and other telescopes.
- Chandra X-Ray Showcase
- GALEX Ultraviolet Showcase
- Spitzer Infrared Showcase
- Current planet positions and constellations.
- Overlays of custom KML content.
- Earth & Sky podcasts gallery.