V849 Ophiuchi or Nova Ophiuchi 1919 was a nova that erupted in 1919, in the constellation Ophiuchus, and reached a blue band brightness of magnitude 7.2.[4] Joanna C. S. Mackie discovered the star while she was examining Harvard College Observatory photographic plates. The earliest plate it was visible on was exposed on August 20, 1919, when the star was at magnitude 9.4. It reached magnitude 7.5 on September 13 of that year.[5][6] In its quiescent state it has a visual magnitude of about 18.8.[7] V849 Ophiuchi is classified as a "slow nova"; it took six months for it to fade by three magnitudes.[4]
 | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Ophiuchus |
| Right ascension | 18h 14m 07.3048s[1] |
| Declination | +11° 36′ 42.1398″[1] |
| Apparent magnitude (V) | 7.6 Max. 18.8 Min.[2] |
| Characteristics | |
| Variable type | Nova[2] |
| Astrometry | |
| Proper motion (μ) | RA: −1.515±0.325[1] mas/yr Dec.: −6.910±0.336[1] mas/yr |
| Parallax (π) | 0.1531 ± 0.2000 mas[1] |
| Distance | 2643+1531 −445[2] pc |
| Other designations | |
| Database references | |
| SIMBAD | data |
All novae are binary stars, and V849 is an eclipsing binary.[4] Its orbital period is 4.146128 hours.[8]
References edit
- ^ a b c d e Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c Schaefer, Bradley E. (2018). "The distances to Novae as seen by Gaia". Monthly Notices of the Royal Astronomical Society. 481 (3): 3033–3051. arXiv:1809.00180. Bibcode:2018MNRAS.481.3033S. doi:10.1093/mnras/sty2388. S2CID 118925493.
- ^ "V849 Ophiuchi". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-08-19.
- ^ a b c d Shafter, A. W.; Misselt, K. A.; Veal, J. M. (August 1993). "The Discovery of Unusual Eclipses in the Light Curves of the Classical Novae DO Aquilae and V849 Ophiuchi". Publications of the Astronomical Society of the Pacific. 105: 853–858. Bibcode:1993PASP..105..853S. doi:10.1086/133244.
- ^ Bailey, S. I. (22 October 1919). "Mackie's Nova". Harvard College Observatory Bulletin. 696: 1. Bibcode:1919BHarO.696....1B. Retrieved 3 February 2022.
- ^ "New Star Discovered at University Observatory". The Harvard Crimson. The Harvard Crimson, Inc. 8 January 1920. Retrieved 3 February 2022.
- ^ Strope, Richard J.; Schaefer, Bradley E.; Henden, Arne A. (July 2010). "Catalog of 93 Nova Light Curves: Classification and Properties". The Astronomical Journal. 140 (1): 34–62. arXiv:1004.3698. Bibcode:2010AJ....140...34S. doi:10.1088/0004-6256/140/1/34. S2CID 118537823. Retrieved 3 February 2022.
- ^ "V0849 Oph". The International Variable Star Index. AAVSO. Retrieved 3 February 2022.
External links edit
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