U Monocerotis
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Monoceros |
| Right ascension | 07h 30m 47.473s |
| Declination | −09° 46′ 36.79″ |
| Apparent magnitude (V) | 5.45 - 7.67 |
| Characteristics | |
| Spectral type | F8eIb - K0pIb |
| U−B color index | +0.47 - +1.22 |
| B−V color index | +0.81 - +1.27 |
| Variable type | RVb |
| Astrometry | |
| Radial velocity (Rv) | 32 km/s |
| Proper motion (μ) | RA: −10.124 mas/yr Dec.: 3.268 mas/yr |
| Parallax (π) | 0.9161±0.0915 mas |
| Distance | 3,600 ± 400 ly (1,100 ± 100 pc) |
| Absolute magnitude (MV) | −4.516 |
| Details | |
| Mass | 2.00+1.07 −0.72 M☉ |
| Radius | 100.3+18.9 −13.2 R☉ |
| Luminosity | 5,480+1,753 −882 L☉ |
| Surface gravity (log g) | 0.0 cgs |
| Temperature | 5,000 (4,930-5,830) K |
| Metallicity | −0.8 |
| Other designations | |
| U Mon, HIP 36521, 2MASS J07304746-0946366, BD−09°2085, HD 59693, TYC 5400-4699-1, GCRV 5005, AAVSO 0726-09, IRAS 07284-0940 | |
| Database references | |
| SIMBAD | data |
U Monocerotis (U Mon) is a pulsating variable star and spectroscopic binary in the constellation Monoceros. The primary star is an RV Tauri variable, a cool luminous post-AGB star evolving into a white dwarf.