XO-5
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Lynx |
| Right ascension | 07h 46m 51.9615s |
| Declination | +39° 05′ 40.461″ |
| Apparent magnitude (V) | 12.13 ± 0.03 |
| Characteristics | |
| Spectral type | G8V + M |
| Apparent magnitude (V) | 12.13 ± 0.03 |
| Apparent magnitude (R) | 11.844 |
| Apparent magnitude (J) | 10.774 ± 0.019 |
| Apparent magnitude (H) | 10.443 ± 0.021 |
| Apparent magnitude (K) | 10.345 ± 0.018 |
| Astrometry | |
| Radial velocity (Rv) | −9.47±0.65 km/s |
| Proper motion (μ) | RA: −21.509(18) mas/yr Dec.: −23.910(13) mas/yr |
| Parallax (π) | 3.6517±0.0173 mas |
| Distance | 893 ± 4 ly (274 ± 1 pc) |
| Absolute magnitude (MV) | 5.06 ± 0.12 |
| Details | |
| Mass | 1.04±0.03 M☉ |
| Radius | 1.13±0.03 R☉ |
| Luminosity | 0.88±0.09 L☉ |
| Surface gravity (log g) | 4.35±0.02 cgs |
| Temperature | 5430±70 K |
| Metallicity [Fe/H] | +0.05±0.06 dex |
| Rotational velocity (v sin i) | 0.7±0.5 km/s |
| Age | 7.0±7.0 Gyr |
| Other designations | |
| Absolutno, TOI-5373, TIC 9155187, GSC 02959-00729, 2MASS J07465196+3905404, UCAC2 45499774 | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
XO-5 is a likely binary star system, made up of a G-type dwarf and a red dwarf companion, located approximately 893 light-years away from Earth in the Lynx constellation. It has a magnitude of about 12 and cannot be seen with the naked eye but is visible through a small telescope.
XO-5 has a suspected red dwarf companion with a temperature of 3500+250
−150 K, on a wide orbit. A 2024 study also identified it as a very likely binary star, with 94% probability.
The star XO-5 is named Absolutno. The name was selected in the NameExoWorlds campaign by the Czech Republic, during the 100th anniversary of the IAU. Absolutno is a fictional miraculous substance in the sci-fi novel Továrna na absolutno (The Factory for the Absolute).