HD 133131
Binary star in the constellation Libra
From Wikipedia, the free encyclopedia
HD 133131 is a binary star in the constellation of Libra. It is 168 light-years (51.5 parsecs) away from the Sun.[3] It consists of two G-type main-sequence stars;[3] neither are bright enough to be seen with the naked eye. The star was first catalogued as a binary in 1972.[11][3]
Both components, HD 133131 A and B, are very similar to the Sun but are far older, about 6 billion years old. They also have low metallicities (50% of solar abundance), and HD 133131A is additionally depleted in heavy elements compared to HD 133131B, indicating a possibly past planetary engulfment event for HD 133131 B.[6]
Planetary system
In 2016, two planets orbiting HD 133131A and one planet orbiting HD 133131B were discovered utilizing the radial velocity method. All three are long-period giant planets.[3]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination (°) |
Radius |
|---|---|---|---|---|---|---|
| b | ≥1.43 MJ | 1.44 | 649 | 0.32 | — | — |
| c | ≥0.63 MJ | 4.79 | 3925 | 0.20 | — | — |
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination (°) |
Radius |
|---|---|---|---|---|---|---|
| b | ≥2.50 MJ | 6.40 | 6119 | 0.62 | — | — |