Jupiter and Saturn-like planets discovered

This video is called Evaporating Exoplanet hd209458b.

From National Geographic:

Smaller “Siblings” of Jupiter, Saturn Discovered

Anne Casselman
for National Geographic News

February 14, 2008

Two newfound extrasolar planets orbiting a star about 5,000 light years away resemble smaller versions of our own Jupiter and Saturn, an international team of astronomers reports.

These planetary “siblings” are about 80 percent as big as our gas giants and orbit a star that’s about half the size of the sun.

What’s more, the smaller planet lies about twice as far from its star as the larger one, just as Saturn is twice as far from the sun as Jupiter.

“The interesting thing about this system is that it looks very similar to our own solar system, but scaled down,” said team leader Scott Gaudi, an astronomer at Ohio State University. (Explore an interactive solar system.)

Gaudi and colleagues from 11 ground-based observatories describe the work in tomorrow’s issue of the journal Science.

The discovery is the first time that an alien planetary system with both Saturn and Jupiter analogues has been spotted, said Sara Seager, a planetary scientist at Massachusetts Institute of Technology, who was not involved in the study.

It’s also only the third time that a Jupiter-mass planet has been found using a technique called gravitational microlensing.

This method has been used to study dark matter and has only recently been applied to the search for so-called exoplanets.

“Until now microlensing has been kind of like a poor cousin in exoplanet sighting,” Seager said.

“So I think it’s a big discovery, because the true power of this technique is just becoming clear.”

First images taken of extrasolar planets: here.

Saturn’s moon Tethys: here.

Could flowers bloom on [Jupiter’s] icy moon Europa? Here.

Facts About Jupiter and Four of Its Moons: here.