R Serpentis
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Serpens |
| Right ascension | 15h 50m 41.73245s |
| Declination | +15° 08′ 01.0810″ |
| Apparent magnitude (V) | 5.2 - 14.4 |
| Characteristics | |
| Evolutionary stage | AGB |
| Spectral type | M5-8e |
| B−V color index | 1.500±0.510 |
| Variable type | Mira |
| Astrometry | |
| Radial velocity (Rv) | 23.8±0.8 km/s |
| Proper motion (μ) | RA: +2.387 mas/yr Dec.: −36.699 mas/yr |
| Parallax (π) | 3.5110±0.2966 mas |
| Distance | 930 ± 80 ly (280 ± 20 pc) |
| Details | |
| Mass | 3.6 M☉ |
| Radius | 79 R☉ |
| Luminosity | 758 L☉ |
| Surface gravity (log g) | 1.55 cgs |
| Temperature | 3,413 K |
| Other designations | |
| R Ser, BD+15°2918, HD 141850, HIP 77615, HR 5894, SAO 101771 | |
| Database references | |
| SIMBAD | data |
R Serpentis is a Mira variable type star in the equatorial constellation of Serpens. It ranges between apparent magnitude 5.16 and 14.4, and spectral types M5e to M8e, over a period of 356.41 days. When it is near maximum brightness, it can be seen with the naked eye under excellent observing conditions. The variability of this star was discovered in 1826 by Karl Ludwig Harding.