Google have replaced their normal logo for a doodle of the Hubble telescope to celebrate its 20th anniversary.

Hovering your mouse pointer over the telescope brings up the words “20th Anniversary of Hubble Telescope Launch by NASA”. Clicking on it brings up the Google search page for “Hubble Telescope”, while clicking on “I’m feeling lucky” brings up the Hubble’s own website. What is much more interesting is if you click your mouse on one of the stars in the picture you are then directed to google sky, a space version of google street-view that allows you to zoom in to see the stars at a very high-resolution; nearly all of the articles covering this Google doodle have missed this.

Hubble is 20 years old today, it is due to be retired in 2013. It orbits Earth every 96 minutes, 360 miles above the surface of our planet, at a speed of five miles per second.

It has beamed hundreds of thousands of images back to Earth, it has allowed scientists to estimate that the universe is around 13 billion years old and has been key to understanding dark matter. 30,000 research projects have been successfully concluded as a result of Hubble.

Its replacement, the James Webb Space Telescope is expected to launch in 2014.