Tatooine's Got Nothing On This Star System
A very compact star system, composed of 2 stars and 3 exoplanets, has been found proving just how diverse and weird our galaxy can be.
Image: Artist's conception of a binary star system with three huge planets; one star has two planets associated with it, and the other star has one planet. Credit: Robin Dienel We've found a lot of Tatooine-like planets -- that is, planets with two stars. In some cases we've even found multiple planets around these systems. But with every new discovery, we find something new that we didn't know was possible in nature.
Take the latest find: two stars, three planets, all happily in harmony with no gravitational preturbances throwing bodies out of the system. What's exciting scientists about the configuration around these stars (HD 133131A and HD 133131B) is just how tightly everything is packed. The team says this is the tightest configuration of stars and planets they have ever seen.
WATCH VIDEO: Can Two-Star Systems Like Tatooine's Exist?
In general, the system could help us better understand the influence of huge planets like Jupiter. According to lead author Johanna Teske of the Carnegie Institution for Science, scientists are trying to figure out if the orbits of planets like Jupiter are long and eccentric. This could affect how other planets are formed.
"The most-common exoplanets detected are so-called super-Earths, which are larger than our planet but smaller than Neptune or Uranus. Given current statistics, Jupiter-sized planets seem fairly rare-having been detected only around a small percentage of stars," the team said in a press release.
"This is of interest because Jupiter's gravitational pull was likely a huge influence on our solar system's architecture during its formative period. So the scarcity of Jupiter-like planets could explain why our home system is different from all the others found to date."
The stars are about 360 Earth-sun distances (or astronomical units) from each other, which is very close for a binary star system with planets. The next-closest star set is about 1,000 AU apart.
There are other mysteries as well: Why the star system has so much hydrogen and helium, instead of elements such as iron and oxygen (which is common in stars that host planets.) And why the stars are not identical twins, but have different compositions -- which could show that one star gobbled baby planets early in its childhood.
A study based on the research will be published in The Astronomical Journal.