Odd trio may help astronomers test ideas about planet formation
Cheongho Han, Chungbuk National University, Republic of Korea
Astronomers have discovered a frozen, rocky planet orbiting one of a pair of faint red stars. Researchers reported the discovery in the July 4 Science.
It’s not the first planet found orbiting one star in a binary, but it is the first to be discovered with microlensing, the temporary brightening of light from a more distant star. This stellar pair is also much more compact than most other binary systems with planets. And it’s the first planet-hosting binary where both stars are M dwarfs, which make up roughly three-quarters of the stars in the galaxy.
Since roughly half of sunlike stars are part of a pair, such duos are a potentially fertile ground for planet hunters. Planets that orbit binary stars can also help astronomers understand how planets form in unusual environments.
The rocky planet is roughly twice as massive as Earth and is about 3,300 light-years away in the