Microsoft's WorldWide Telescope, a free tool that allows users to explore images of the sky at night, will be available at the end of May.

WorldWide Telescope was developed using the company's Visual Experience Engine and blends terabytes of images and data amassed from telescopes around the world including Hubble.

"The WorldWide Telescope takes very complex data gathered over many years from many telescopes and makes it accessible," said Microsoft chairman Bill Gates during a speech in Jakarta.

Described as "an observatory on your desktop", WorldWide Telescope is widely seen as a rival to Google Sky which launched in August 2007.

"It is going to change the way we do astronomy," said Dr Roy Gould from the Harvard Centre for Astrophysics.

According to Gould the WorldWide Telescope project currently holds information on around 300 solar systems.

"I think this will have as profound an impact on the way we view the universe as Galileo did with the telescope a long time ago," he said.