Jonckheere 320
| Emission nebula | |
|---|---|
| Planetary nebula | |
Image by the Hubble Space Telescope | |
| Observation data: J2000 epoch | |
| Right ascension | 05h 05m 34.32s[1] |
| Declination | +10° 42′ 22.7″[1] |
| Distance | ~6,881[2]-19,569 ly |
| Apparent diameter | 11" x 8" |
| Constellation | Orion |
| Designations | PK 190-17 1, PN G190.3-17.7, IRAS 05028+1038, SCM 3[1] |
Jonckheere 320 (J320) is an extremely small, bright, elongated planetary nebula with two or three bipolar lobes. It was discovered by French astronomer R. Jonckheere in 1911 and was initially classified as a binary star system. In 1916, R. Jonckheere revisited J320 using the Royal Observatory, Greenwich and realized it was not a binary star system.[3]
Characteristics
[edit]J320 is a Type II low-excitation PN[4] and a polypolar planetary nebula.[5] The distance of J320 is uncertain, with estimates ranging form ~2.11[2] and ~6 kpc.[6]
The apparent size of the nebula is exceptionally small at only 11" x 8" and 7.7" x 4.8" for the inner halo. The physical diameter is estimated to be ~0.7 ly across its main axis.[7]
The central core is surrounded by high-velocity knots.[5]
Central Star
[edit]The nebula was originally mistaken for a binary system.[3] The central star is a hot, evolved white dwarf precursor with a T_eff = 85,000 K and a mass = 0.79 M⊙. The star was classified as a weak emission line star.[8] The star has an apparent magnitude of ~13.5 and the luminosity is 40x of the Sun.[5]
References
[edit]- 1 2 3 "Jonckheere 320". simbad.cds.unistra.fr.
- 1 2 Phillips, J. P. (2002). "The Distances of Planetary Nebulae: A Scale Based upon Nearby Sources". The Astrophysical Journal. 139 (1): 199–217. Bibcode:2002ApJS..139..199P. doi:10.1086/338028.
- 1 2 Jonckheere, R. (March 1916). "A new stellar nebula". The Observatory. 39: 134–135. Bibcode:1916Obs....39..134J.
- ↑ Martins, L. P.; Viegas, S. M. (June 2002). "Gas temperature and excitation classes in planetary nebulae". Astronomy & Astrophysics. 387 (3): 1074–1082. Bibcode:2002A&A...387.1074M. doi:10.1051/0004-6361:20020469.
- 1 2 3 Harman, D. J.; Bryce, M.; López, J. A.; Meaburn, J.; Holloway, A. J. (March 2004). "J320 (PN G190.3—17.7) as a poly-polar planetary nebula surrounded by point-symmetric knots". Monthly Notices of the Royal Astronomical Society. 348 (3): 1047–1054. Bibcode:2004MNRAS.348.1047H. doi:10.1111/j.1365-2966.2004.07427.x.
- ↑ Cahn, J. H.; Kaler, J. B.; Stanghellini, L. (September 1992). "A catalogue of absolute fluxes and distances of planetary nebulae". Astronomy & Astrophysics. 94: 399–452. Bibcode:1992A&AS...94..399C.
- ↑ McCarthy, J. K.; Mendez, R. H.; Kudritzki, R.-P.; Habinge, H. J.; Lamers, H. J. G. L. M. (1997). Proc. IAU Symp. 180, Planetary Nebulae. Dordrecht: Kluwer Academic Publishers. p. 122.
- ↑ Aller, L. H.; Keyes, C. D. (December 1985). "A survey of the central-star characteristics of mostly faint planetary nebulae". Publications of the Astronomical Society of Japan. 97: 1142–1148. Bibcode:1985PASP...97.1142A. doi:10.1086/131677.