All names: SDSS J084001.22+452933.3, US 1431, SDSS J084001.22+452933.8, J0840+4529, GALEX J084001.2+452933, Gaia EDR3 917539532801552640, Gaia DR3 917539532801552640, Gaia DR2 917539532801552640, SDSS J084001.23+452933.7
| Parameter | Unit | Gaia EDR3 | Pan-STARRS DR1 | SDSS DR12 | Coutu et al. 2019 | Gaia DR2 | Stilism | Vincent et al. 2024 | Simbad | Kleinman et al. 2013 | Vincent et al. 2023 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Right ascension | 08 40 01.21 (0.1) | 08 40 01.22 | 08 40 01.22 | 08 40 01.21 (0.2) | 08 40 01.21 | 08 40 01.22 (0.1) | 08 40 01.23 | ||||
| Declination | 45 29 33.18 (0.09) | 45 29 33.84 | 45 29 33.89 | 45 29 33.21 (0.1) | 45 29 33.18 | 45 29 33.89 (0.09) | 45 29 33.73 | ||||
| Spectral type | DQ | DQ | DQ | DQ | DQ | ||||||
| Effective temperature | [K] | 7798.0 (185) | 8021.0 (165) | 10094.0 (26) | |||||||
| log(g) | [cgs] | 7.98 | 8.01 (0.04) | 9.51 (0.4) | |||||||
| Mass | [M☉] | 0.5641 | 0.579 (0.03) | ||||||||
| log(Luminosity) | [L☉] | ||||||||||
| Cooling age | [Gyr] | 1.1600 | |||||||||
| log(H/He) | |||||||||||
| log(C/He) | -5.6595 (0.05) | ||||||||||
| log(Ca/He) | |||||||||||
| log(Ca/H) | |||||||||||
| log(N/He) | |||||||||||
| log(O/He) | |||||||||||
| log(Na/He) | |||||||||||
| log(Mg/He) | |||||||||||
| log(Al/He) | |||||||||||
| log(Si/He) | |||||||||||
| log(P/He) | |||||||||||
| log(S/He) | |||||||||||
| log(Cl/He) | |||||||||||
| log(Sc/He) | |||||||||||
| log(Ti/He) | |||||||||||
| log(V/He) | |||||||||||
| log(Cr/He) | |||||||||||
| log(Mn/He) | |||||||||||
| log(Fe/He) | |||||||||||
| log(Co/He) | |||||||||||
| log(Ni/He) | |||||||||||
| log(Cu/He) | |||||||||||
| log(Zn/He) | |||||||||||
| log(Ga/He) | |||||||||||
| log(Ge/He) | |||||||||||
| log(Sr/He) | |||||||||||
| Parallax | [mas] | 9.29 (0.2) | 9.52 | 9.52 (0.2) | 9.29 | 9.29 (0.2) | |||||
| Distance | [pc] | 107.61 (2) | 105.08 (2) | 105.08 (2) | 107.61 | 107.61 (2) | |||||
| Composition | He | ||||||||||
| Proper motion (right ascension) | [mas/yr] | -6.709906995 (0.1) | -6.555434749 (0.3) | -6.71 (0.1) | |||||||
| Proper motion (declination) | [mas/yr] | -43.9377968 (0.1) | -44.21934401 (0.2) | -43.938 (0.1) | |||||||
| Variability | |||||||||||
| Magnetic | |||||||||||
| Bd | [MG] | ||||||||||
| Infrared excess (disk) | |||||||||||
| Binarity | |||||||||||
| B magnitude | 18.50 | ||||||||||
| V magnitude | |||||||||||
| R magnitude | |||||||||||
| I magnitude | |||||||||||
| J magnitude | |||||||||||
| H magnitude | |||||||||||
| K magnitude | |||||||||||
| u magnitude | 18.60 (0.02) | 18.60 (0.02) | 18.60 (0.03) | ||||||||
| g magnitude | 18.30 (0.007) | 18.30 (0.007) | 18.29 (0.02) | ||||||||
| r magnitude | 18.26 (0.007) | 18.25 (0.007) | 18.25 (0.01) | ||||||||
| i magnitude | 18.35 (0.01) | 18.35 (0.01) | 18.35 (0.01) | ||||||||
| z magnitude | 18.49 (0.03) | 18.49 (0.03) | 18.49 (0.03) | ||||||||
| G magnitude | 18.22 (0.02) | 18.25 | 18.22 | 18.22 (0.003) | |||||||
| BP magnitude | 18.30 (0.02) | 18.26 | |||||||||
| RP magnitude | 18.03 (0.02) | 18.02 | |||||||||
| Pan g magnitude | 18.29 (0.003) | ||||||||||
| Pan r magnitude | 18.27 (0.002) | ||||||||||
| Pan i magnitude | 18.36 (0.005) | ||||||||||
| Pan z magnitude | 18.45 (0.009) | ||||||||||
| Pan y magnitude | 18.56 (0.02) | ||||||||||
| E(B-V) | 0.004 | ||||||||||
* Constant surface field
Spectra without link are available upon request
The Montreal White Dwarf Database is produced and maintained by Prof. Patrick Dufour (Université de Montréal) and Dr. Simon Blouin (University of Victoria). Please send database updates, corrections, suggestions or bug reports to patrick.dufour@umontreal.ca.