A Solar System Rich in Planets
If you're looking for life outside of our solar system, it makes sense to look for solar systems and planets like our own. You'd want a solar system with a Sun like ours, with lots of planets orbiting around it. One of those planets should be the size of Earth and traveling at a distance around its star similar to the distance that we're traveling around our Sun. Scientists haven't found that perfect solar system or planet yet—we're still unique—but astronomers got a bit closer recently with the discovery of a Sun-like star that is particularly rich in planets.
The star HD 10180 is about 127 light years away. Astronomers using a telescope in Chile detected the signals of five Neptune-sized planets rotating around the star at periods ranging from 6 to 600 Earth days. They also suspect there may be two other planets, one that is similar to Saturn and orbiting HD 10180 every 2,200 days and another about 1.4 times the size of Earth and orbiting so close and fast to its sun that its year is only 1.18 Earth days long.
Astronomers know of at least 15 systems with three or more planets, but this is the first one to have so many large planets orbiting so close to its star, all in nearly circular paths, and it's the first to lack a Jupiter-like gas giant.