Scientists Discover A Super-Compact Star System

By Rudie Obias | 9 years ago

Astronomers and researchers using NASA’s pioneering Kepler space observatory have discovered what they are describing as the most “crowded” alien planetary system yet found. All five planets in the solar system surround a star called “KOI-500,” and orbit at least twelve times closer to their sun than the Earth does to ours.

As reported by, the system is approximately 1,100 light-years away, in the constellation Lyra, the harp. While KOI-500’s mass is about the same as that of our Sun, but only three quarters of its diameter. The star is about 1 billion years old, which is less than one-quarter of our home star’s age.

The planets in this super-packed star system vary from 1.3 to 2.6 times the size of Earth. The “years” on each planet are understandably short as well. Relative to the Earth, each planet only takes a few days to make a complete circuit around KOI-500. Astronomers have calculated each planet’s “yearly” duration in Earth days, which are 1.0, 3.1, 4.6, 7.1, and 9.5 days long, respectively.

Darin Ragozzine, the lead author of the NASA planetary study and a scientist at the University of Florida at Gainesville, explained:

All five planets zip around their star within a region 150 times smaller in area than the Earth’s orbit, despite containing more material than several Earths. At this rate, you could easily pack in 10 more planets, and they would still all fit comfortably inside the Earth’s orbit.

Ragozzine notes that the most interesting thing about the compact solar system is its four outer planets, which seem to have a synchronized orbit like no other solar system NASA astronomers have discovered. “These four planets come back to a similar orbital configuration about every 191 days,” says Ragozzine. NASA Astronomers have called this occurrence “four-body resonance.”

Below is a handy infographic that illustrates the planets of KOI-500 and their closely clustered system.