GP Comae Berenices
An ultraviolet band light curve for GP Comae Berenices, adapted from Smak (1975). The error bar shown on the leftmost point applies to all points. | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Coma Berenices |
| Right ascension | 13h 05m 42.401s |
| Declination | +18° 01′ 03.76″ |
| Apparent magnitude (V) | 15.69 |
| Characteristics | |
| Evolutionary stage | White dwarf |
| Spectral type | DBe |
| Apparent magnitude (g) | 15.929 |
| Variable type | AM CVn |
| Astrometry | |
| Proper motion (μ) | RA: −344.92±0.06 mas/yr Dec.: 34.85±0.06 mas/yr |
| Parallax (π) | 13.7306±0.0452 mas |
| Distance | 237.5 ± 0.8 ly (72.8 ± 0.2 pc) |
| Details | |
| Mass | 0.59±0.09 M☉ |
| Temperature | 14,800±500 K |
| Other designations | |
| Gaia DR2 3938156295111047680, G 61-29, LTT 18284, WD 1303+18, 2MASS J13054243+1801039 | |
| Database references | |
| SIMBAD | data |
GP Comae Berenices, abbreviated to GP Com and also known as G 61-29, is a star system composed of a white dwarf orbited by a planetary mass object, likely the highly eroded core of another white dwarf star. The white dwarf is slowly accreting material from its satellite at a rate of (3.5±0.5)×10−11 M☉/year and was proven to be a low-activity AM CVn star. The star system is showing signs of a high abundance of ionized nitrogen from the accretion disk around the primary.
In 1971, Brian Warner discovered that the star, then known as G61-29, is a variable star. it was given its variable star designation, GP Comae Berenices, in 1975.