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."
Wobble vs. Lensing
The most common planet-hunting technique is known as the Doppler method.
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