SDSS J1228+1040

SDSS J1228+1040

Doppler imaging of the calcium gas around SDSS J1228+1040. The map is "inside-out", with the outer part being closer to the white dwarf
Credit: University of Warwick/C. Manser/ESO
Observation data
Epoch J2000      Equinox J2000
Constellation Virgo
Right ascension 12h 28m 59.93s
Declination +10° 40 33.05
Characteristics
Evolutionary stage white dwarf
Spectral type DAZ
Apparent magnitude (G) 16.4
Astrometry
Proper motion (μ) RA: -50.254 ±0.069 mas/yr
Dec.: -24.729 ±0.049 mas/yr
Parallax (π)7.7634±0.0662 mas
Distance420 ± 4 ly
(129 ± 1 pc)
Details
Mass0.705 ±0.051 M
Radius0.01169 ±0.00078 R
Surface gravity (log g)8.150 ±0.089 cgs
Temperature20,713 ±281 K
Agecooling age: 100 ±5 Myr
total age: 170 Myr
Other designations
GALEX J122859.9+104032, WD 1226+110, WD 1226+109, LAMOST J122859.93+104032.9, SDSS J122859.93+104032.9, WIRED J122859.93+104032.9, WISE J122859.87+104032.8
Database references
SIMBADdata

SDSS J1228+1040 (SDSS J122859.93+104032.9, WD 1226+110) is a white dwarf with a debris disk around it. The disk formed when a planetary body was tidally disrupted around the white dwarf. It is the first gaseous disk discovered around a white dwarf.

SDSS J1228+1040 was first identified as a white dwarf in 2006 from SDSS spectroscopic data. These observations identified it as a DA white dwarf, which indicates the detection of hydrogen.