All names: WD 1644+424, SDSS J164615.60+422349.2, [SGR2010] J1646+4223, Gaia DR2 1356644653998341248, SDSS J164615.60+422349.3, Gaia DR3 1356644653998341248, [HHD2009] SDSS J1646+4223, SBC9 3393, WIRED J164615.60+422349.2, Gaia EDR3 1356644653998341248
| Parameter | Unit | Gaia EDR3 | Pan-STARRS DR1 | SDSS DR12 | Gaia DR2 | Stilism | sdss-wdms.org (29/04/2016) | Tremblay et al. 2011 | Simbad | Eisenstein et al. 2006 | White Dwarf Catalog (McCook & Sion 1999) | Kleinman et al. 2013 | Vincent et al. 2023 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Right ascension | 16 46 15.60 (0.08) | 16 46 15.61 | 16 46 15.60 (0.1) | 16 46 15.60 | 16 46 15.61 (0.08) | 16 46 15.61 | 16 46 14.88 | 16 46 15.60 | |||||
| Declination | 42 23 48.98 (0.1) | 42 23 49.28 | 42 23 48.99 (0.2) | 42 23 49.20 | 42 23 49.28 (0.1) | 42 23 49.24 | 42 23 45.96 | 42 23 49.29 | |||||
| Spectral type | DA+M | DA | DA+M | DA+M | DA+ME | DA+M | DA | ||||||
| Effective temperature | [K] | 17707.0 (516) | 18410.0 (620) | 8853.0 (56) | 8551.0 (73) | ||||||||
| log(g) | [cgs] | 7.83 (0.1) | 7.89 (0.1) | 7.99 (0.07) | 7.59 (0.1) | ||||||||
| Mass | [M☉] | 0.53 (0.06) | 0.56 (0.06) | ||||||||||
| log(Luminosity) | [L☉] | ||||||||||||
| Cooling age | [Gyr] | 0.0891 | |||||||||||
| log(H/He) | |||||||||||||
| log(C/He) | |||||||||||||
| log(Ca/He) | |||||||||||||
| log(Ca/H) | |||||||||||||
| log(C/H) | |||||||||||||
| log(N/H) | |||||||||||||
| log(O/H) | |||||||||||||
| log(Na/H) | |||||||||||||
| log(Mg/H) | |||||||||||||
| log(Al/H) | |||||||||||||
| log(Si/H) | |||||||||||||
| log(P/H) | |||||||||||||
| log(S/H) | |||||||||||||
| log(Sc/H) | |||||||||||||
| log(Ti/H) | |||||||||||||
| log(Cr/H) | |||||||||||||
| log(Mn/H) | |||||||||||||
| log(Fe/H) | |||||||||||||
| log(Ni/H) | |||||||||||||
| Parallax | [mas] | 2.84 (0.1) | 2.90 (0.2) | 2.84 (0.1) | |||||||||
| Distance | [pc] | 352.60 (12) | 344.74 (19) | 560.00 (59) | 352.60 (12) | ||||||||
| Composition | H | ||||||||||||
| Proper motion (right ascension) | [mas/yr] | -6.926090385 (0.1) | -6.735817298 (0.3) | -6.926 (0.1) | -4.5 | ||||||||
| Proper motion (declination) | [mas/yr] | -18.54991814 (0.1) | -17.80099084 (0.4) | -18.55 (0.1) | -21.4 | ||||||||
| Variability | |||||||||||||
| Magnetic | |||||||||||||
| Bd | [MG] | ||||||||||||
| Infrared excess (disk) | |||||||||||||
| Binarity | WDMS | WDMS | WDMS | ||||||||||
| B magnitude | |||||||||||||
| V magnitude | |||||||||||||
| R magnitude | |||||||||||||
| I magnitude | |||||||||||||
| J magnitude | |||||||||||||
| H magnitude | |||||||||||||
| K magnitude | |||||||||||||
| u magnitude | 18.67 (0.02) | 18.75 | 18.75 (0.02) | 18.75 (0.02) | 18.74 | 18.73 (0.02) | |||||||
| g magnitude | 18.43 (0.007) | 18.43 | 18.39 (0.01) | 18.43 (0.01) | 18.41 | 18.41 (0.01) | |||||||
| r magnitude | 18.55 (0.008) | 18.55 | 18.55 (0.01) | 18.55 (0.02) | 18.56 | 18.54 (0.02) | |||||||
| i magnitude | 17.95 (0.008) | 17.96 | 17.95 (0.01) | 17.96 (0.01) | 17.95 | 17.95 (0.01) | |||||||
| z magnitude | 17.25 (0.01) | 17.22 | 17.23 (0.02) | 17.22 (0.02) | 17.21 | 17.22 (0.02) | |||||||
| G magnitude | 18.17 (0.02) | 18.18 | 18.17 (0.003) | ||||||||||
| BP magnitude | 18.50 (0.02) | 18.48 | |||||||||||
| RP magnitude | 17.50 (0.01) | 17.49 | |||||||||||
| Pan g magnitude | 18.45 (0.006) | ||||||||||||
| Pan r magnitude | 18.57 (0.004) | ||||||||||||
| Pan i magnitude | 18.00 (0.004) | ||||||||||||
| Pan z magnitude | 17.42 (0.008) | ||||||||||||
| Pan y magnitude | 17.05 (0.007) | ||||||||||||
| E(B-V) | 0.020 | ||||||||||||
* 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.