QR Andromedae
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Right ascension00h 19m 49.9253s[2]
Declination+21° 56′ 52.167″[2]
Apparentmagnitude(V)12.16 – 13.07 variable[3]
 The visual band light curve of QR Andromedae (adapted from Matsumoto (1996)), The phase is with respect to the 15.85 hour orbital period.[1] | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Andromeda |
| Right ascension | 00h 19m 49.9253s[2] |
| Declination | +21° 56′ 52.167″[2] |
| Apparent magnitude (V) | 12.16 – 13.07 variable[3] |
| Characteristics | |
| Spectral type | pec(e)[3] |
| Apparent magnitude (B) | 12.38[4] |
| Apparent magnitude (R) | 11.86[4] |
| Apparent magnitude (G) | 12.2395[2] |
| Apparent magnitude (J) | 12.432[5] |
| Apparent magnitude (H) | 12.295[5] |
| Apparent magnitude (K) | 12.092[5] |
| Variable type | Algol[3] |
| Astrometry | |
| Proper motion (μ) | RA: 18.469±0.071 [2] mas/yr Dec.: −5.529±0.079[2] mas/yr |
| Parallax (π) | 0.4993±0.0452 mas[2] |
| Distance | 6,500 ± 600 ly (2,000 ± 200 pc) |
| Orbit | |
| Period (P) | 0.6604 days[4] |
| Semi-amplitude (K1) (primary) | 61.8±4.4[6] km/s |
| Other designations | |
| 2MASS J00194992+2156521, AAVSO 0014+21 | |
| Database references | |
| SIMBAD | data |
QR Andromedae (often abbreviated to QR And) is an eclipsing binary star in the constellation Andromeda. Its maximum apparent visual magnitude is 12.16, but its light curve shows clearly eclipsing events where its brightness can drop to a magnitude of 13.07.[6] This leads to its classification as an Algol variable star.[3]
The optical spectrum of QR Andromedae is not of a typical stellar blackbody, but is peculiar with many emission lines,[3] the strongest being the HeII line. Balmer series and OVI lines are also present. It was also one of the super soft X-ray sources discovered by ROSAT satellite, one of the few source of this kind observed so far in the Milky Way.[6]
