Fomalhaut C
Fomalhaut C, also designated LP 876-10, is the distant third star of the Fomalhaut system. It is about five degrees from Fomalhaut, roughly halfway between it and the Helix Nebula. It is currently 2.5 light-years (0.77 pc) from Fomalhaut (A), and 3.2 light-years away from Fomalhaut B (0.987 pc). The entire system is only around 25 light-years (7.7 pc) from the Solar System. It was originally catalogued as a lone red dwarf, until October 2013, when Eric Mamajek announced that the star had a distance, velocity and color-magnitude position consistent with it being part of the Fomalhaut system. It was most likely catalogued with no relation to Fomalhaut due to the fact that it is in the Aquarius constellation, while the rest of the system are in the Piscis Austrinus constellation.
Fomalhaut C Location of Fomalhaut C in the constellation Aquarius | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aquarius |
| Right ascension | 22h 48m 04.49285s |
| Declination | −24° 22′ 07.7178″ |
| Apparent magnitude (V) | 12.624 |
| Characteristics | |
| Spectral type | M4V |
| Astrometry | |
| Radial velocity (Rv) | 5.77±0.58 km/s |
| Proper motion (μ) | RA: 331.609 mas/yr Dec.: −183.805 mas/yr |
| Parallax (π) | 130.2707 ± 0.0325 mas |
| Distance | 25.037 ± 0.006 ly (7.676 ± 0.002 pc) |
| Absolute magnitude (MV) | 13.21 ± 0.02 |
| Details | |
| Mass | 0.18 ± 0.02 M☉ |
| Luminosity (visual, LV) | 0.004603 L☉ |
| Temperature | 3,132 ± 65 K |
| Metallicity [Fe/H] | −0.1 dex |
| Rotation | 0.466 days |
| Other designations | |
| Database references | |
| SIMBAD | data |