A star just 10 light-years away may provide a fascinating glimpse into the beginnings of our own Solar System.
The star, called Epsilon Eridani, is similar to our Sun but about one-fifth the age, and contains debris disks that are the hallmark of the formation of a planetary system.
A new study by Iowa State University, published in The Astronomical Journal, examined the disks of debris around the star. They found that the star has separate inner and outer disk structures, similar to the asteroid belt between Earth and Mars and the Kuiper Belt beyond Neptune in our own Solar System.
“This star hosts a planetary system currently undergoing the same cataclysmic processes that happened to the Solar System in its youth, at the time in which the Moon gained most of its craters, Earth acquired the water in its oceans, and the conditions favorable for life on our planet were set,” co-author Massimo Marengo said in a summary of the study.
This period is known as the late heavy bombardment (LHB), when it’s thought that comets from the Kuiper Belt and possibly the Oort Cloud further out too were sent flying inwards. This is thought to have happened between 4.1 and 3.8 billion years ago in our Solar System, which is about 4.6 billion years old.
We can see evidence for this period today in the age of craters on the Moon and other bodies. Samples from the Apollo missions found that many lunar craters heralded from this time period. The migration of Jupiter and Saturn to different orbits is thought to have caused the event, kicking Neptune further out and sending comets inwards.
A model of epsilon Eridani compared to our own Solar System. NASA/SOFIA/Lynette Cook
It’s not clear what process is taking place in Epsilon Eridani. But we do know there’s a Jupiter-mass planet there, called Epsilon Eridani b, at the edge of an inner asteroid belt roughly at the same position as our own. A second asteroid belt is at about the same position as the orbit of Uranus in our system.
“The similarity of the structure of the Epsilon Eridani system to our Solar System is remarkable, although Epsilon Eridani is much younger than our Sun,” NASA said in a statement.
These latest findings were made using NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA), a plane equipped with a telescope that flies at about 13,700 meters (45,000 feet) to observe the universe.
“[W]e can now say with great confidence that there is a separation between the star’s inner and outer belts,” Marengo said in a statement. “There is a gap most likely created by planets. We haven’t detected them yet, but I would be surprised if they are not there.”