 Visual band light curves for the 1973 and 1991 eruptions of V1017 Sagittarii, adapted from Salazar et al. (2017) [1] | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Sagittarius |
| Right ascension | 18h 32m 04.4738s [2] |
| Declination | −29° 23′ 12.5935″ [2] |
| Apparent magnitude (V) | 4.5±2Max. 13.5 Min. [3] |
| Characteristics | |
| Spectral type | G5IIIp / white dwarf |
| Variable type | eclipsing recurrent nova (NR+E) |
| Astrometry | |
| Radial velocity (Rv) | 15 km/s |
| Proper motion (μ) | RA: 5.241±0.086 [2] mas/yr Dec.: −10.392±0.066 [2] mas/yr |
| Parallax (π) | 0.7892±0.0437 mas [2] |
| Distance | 1269+84 −60 [3] pc |
| Other designations | |
| Nova Sagittarii 1919, AAVSO 1825-29, Gaia DR2 4048251562703375488, 2MASS J18320447-2923125 [4] | |
| Database references | |
| SIMBAD | data |
V1017 Sagittarii is a cataclysmic variable star system in the constellation Sagittarius. Ida E. Woods discovered the star on Harvard College Observatory photographic plates, in 1919. [5] During that eruption, the star reached magnitude 7. Its other eruptions in 1901, 1973 and 1991 only reached magnitude 10, leading it to be reclassified from a recurrent nova to a dwarf nova. [6]
After the eruption of 1919, the orbital period of the binary system has decreased by 0.0273±0.0061%, to the 5.786290±0.000032 days. [1] Physical models cannot explain the orbital change of such sign and magnitude as in 2019. [7]
