Scientists have found the spectral imprints of water vapor in starlight filtered through the atmosphere of a giant gas planet outside our solar system.

Combined with a study announced earlier this year, the new finding provides strong evidence that extrasolar planets are as rich in water as the worlds in our solar system, scientists say.

The finding is detailed in the July 11 issue of the journal Nature.

First solid evidence

Called HD 189733b, the planet belongs to a class of gas giants called "hot Jupiters," which orbit their stars from a distance closer than Mercury is to our sun. The fiery world is about 15 percent bigger than Jupiter and orbits a sun-like star located 64 light-years away in the constellation of Vulpecula, the Fox. It has an average temperature of 1,340 degrees Fahrenheit (727 degrees Celsius) and zips around its star in just two days.

"We're thrilled to have identified clear signs of water on a planet

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