CHICAGO — A host of amateur astronomers have helped researchers discover a distant solar system remarkably similar to our own, according to a study released Thursday by Science magazine.
Initial observations found two planets orbiting a star some 5,000 light years away which appear to be slightly smaller versions of our own Jupiter and Saturn.
Just 25 multi-planet solar systems have been mapped so far and this is the first one that really seems to resemble our own, said lead author Scott Gaudi of Ohio State University.
"It's like a scaled-down version of our solar system," he said in a telephone interview.
These planets orbit a star which is "smaller, colder and dimmer than the sun," Gaudi said, adding that the planets are closer to their parent star than Jupiter and Saturn and a bit cooler.
"We don't know anything about them except their mass," he said.
One is roughly 70 percent of Jupiter's weight and the other about 90 percent of Saturn's mass. They are more than a thousand times farther away from Earth than the nearest star.
"We're pretty sure they're (made of) gas like Jupiter and Saturn, but we probably won't be able to find out, since they are so far away."
The two planets were revealed when the star they orbit passed in front of the orbit of a more distant star. This magnified the light of the more distant star as it was bent by the gravitation fields of the planets.
Gaudi and his team determined the mass of the planets by calculating how the light changed, a technique called gravitational microlensing.
But since there was just a two-week period from late March through early April of 2006 when this phenomenon could be observed, Gaudi and his team needed all the help they could get in collecting observations.
They enlisted the help of amateur astronomers in the southern hemisphere and professionals from 11 observatories in countries around the world, including Chile, Tasmania, New Zealand, the Canary Islands, Israel and the United States.
"It's more of a coordination effort than a technology effort," Gaudi said. "We use whatever we can get our hands on."
Many of the amateurs used small telescopes "that could fit on a desktop," Gaudi explained.
"What's more important for us (than size) is location," he said. "To see the center of the galaxy, you have to be in the southern hemisphere."
Jennie McCormick of Auckland, New Zealand, who helped collect the data, was happy to be of use.
"As an amateur astronomer working with a small telescope from her backyard at the bottom of the world, how does one truly describe being involved in such an exciting and important discovery as this? Fantastic!" McCormick wrote in an email.
"The thrill of the chase is better still, and working with the guys is a dream come true."
As for life on these planets? There's "almost certainly not life on them -- they're too far from their parent star," Gaudi said.