  | |
 Recurrent nova RS Ophiuchi in eruption of February 2006 | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Ophiuchus |
| Right ascension | 17h 50m 13.2s |
| Declination | −06° 42′ 28″ |
| Apparent magnitude (V) | 9.6 – 13.5 (quiet), < 5 (burst) |
| Characteristics | |
| Spectral type | K5.5/M0IIIe / White dwarf |
| Variable type | Recurrent nova |
| Astrometry | |
| Distance | 3,900 – 6,500 ly (1,200 – 2,000[1] pc) |
| Other designations | |
| Database references | |
| SIMBAD | data |
RS Ophiuchi (RS Oph) is a recurrent nova system approximately 5,000 light-years away in the constellation Ophiuchus. In its quiet phase it has an apparent magnitude of about 12.5. It has been observed to erupt in 1898, 1933, 1958, 1967, 1985, 2006 and 2021 and reached about magnitude 5 on average. A further two eruptions, in 1907 and 1945, have been inferred from archival data. The recurrent nova is produced by a white dwarf star and a red giant in a binary system. About every 15 years, enough material from the red giant builds up on the surface of the white dwarf to produce a thermonuclear explosion. The white dwarf orbits close to the red giant, with an accretion disc concentrating the overflowing atmosphere of the red giant onto the white dwarf.
- ^ Barry, R. K.; Mukai, K.; Sokoloski, J. L. (2008). "On the Distance of RS Ophiuchi". RS Ophiuchi (2006) and the Recurrent Nova Phenomenon. ASP Conference Series. 401: 52. Bibcode:2008ASPC..401...52B.