It appears that a nearby solar system closely resembles our own solar system, raising the possibility it could harbor Earth-like planets. NASA astronomers reported that the triple-ringed star has an asteroid belt and a Jupiter-like giant planet in roughly the same orbits as in our own solar system. Moreover, the presence of these three rings of material implies that unseen planets confine and shape them.
Only 850 million years old, a fifth the age of Earth's sun and 10 light-years away, Epsilon Eridani resembles a younger twin to our solar system. The star's asteroid belts were found using the Spitzer space telescope.
"Studying Epsilon Eridani is like having a time machine to look at our solar system when it was young," said Smithsonian astronomer Massimo Marengo of Harvard-Smithsonian’s Center for Astrophysics. Marengo is a co-author of the discovery paper, which will appear in the January 10 issue of The Astrophysical Journal.
Asteroid belts are rocky and metallic debris left over from the early stages of planet formation. Their presence around other stars signals that rocky planets like Earth could be orbiting in the system's inner regions, with massive gas planets circling near the belts' rims. Our solar system has a rocky asteroid belt between Mars and Jupiter, about 3 astronomical units from the Sun.
The popular star was also one of the first to be searched for signs of advanced alien civilizations using radio telescopes in 1960. At that time, astronomers did not know of the star's young age.
One of the two possible planets previously identified around Epsilon Eridani was discovered in 2000. The planet is thought to orbit at an average distance of 3.4 astronomical units from the star, just outside the innermost asteroid belt identified by Spitzer.