| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Taurus |
| Right ascension | 03h46m 46.517s[1] |
| Declination | +24° 56′ 02.67″[1] |
| Apparent magnitude (V) | 19.0[2] |
| Characteristics | |
| Evolutionary stage | white dwarf |
| Spectral type | DX13[3] |
| U−B color index | +0.30[2] |
| B−V color index | +1.44[2] |
| Astrometry | |
| Proper motion (μ) | RA: 520.177[1] mas/yr Dec.: −1,157.434[1] mas/yr |
| Parallax (π) | 25.2941 ± 0.2085 mas[1] |
| Distance | 129 ± 1 ly (39.5 ± 0.3 pc) |
| Absolute magnitude (MV) | 16.80[3] |
| Details | |
| Mass | 0.553±0.031[4] M☉ |
| Radius | 0.011±0.001[4] R☉ |
| Luminosity | 0.000048[4] L☉ |
| Temperature | 4,197±83[5] K |
| Age | 11.49±1.51[4] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
WD 0343+247 is a white dwarf in the ecliptic constellationofTaurus. It was discovered in 1997 when examination of photographs taken for a survey of brown dwarfs in the Pleiades revealed a faint star with high proper motion. It is one of the coolest white dwarfs known, with an effective temperature estimated to be approximately 3,800 K, equivalent to a spectral type of M0.[7] Although referred to as WD 0346+246 in the discovery paper, it is more correctly designated WD 0346+247.[3]
Recent studies using NASA's Spitzer Space Telescope and MDM Observatory's 2.4-meter telescope (near Tucson, Arizona, USA) shows that this white dwarf (together with another one: SDSS J110217.48+411315.4) has a low (for white dwarfs) surface temperature between 3,700 and 3,800 K due to it being 11 to 12 billion years old.[5]
