A0620-00

A0620-00
Observation data
Epoch J2000      Equinox J2000
Constellation Monoceros
Right ascension 06h 22m 44.503s[1]
Declination −00° 20 44.72[1]
Apparent magnitude (V) 11.2[1]
Characteristics
Spectral type K5 V + black hole[2]
Variable type X-ray nova, Ellipsoidal[3]
Astrometry
Radial velocity (Rv)−5 ± 12[4] km/s
Distance3460 ± 390 ly
(1060 ± 120[2] pc)
Orbit
Period (P)7.75234 ± 0.00010[4] hr
Inclination (i)50.98 ± 0.87[2]°
Periastron epoch (T)JD 2446082.7481 ± 0.0008[4]
Semi-amplitude (K1)
(primary)
457 ± 8[4] km/s
Details[2]
Black hole
Mass6.61 ± 0.25 M
K-type star
Mass0.40 ± 0.045 M
Other designations
1A 0620-00, INTREF 297, Nova Mon 1917, Nova Mon 1975, Mon X-1, V616 Mon[1]
Database references
SIMBADdata

A0620-00 (abbreviated from 1A 0620-00) is a binary star system in the constellation of Monoceros.

A0620-00 consists of two objects. The first object is a K-type main-sequence star with a spectral type of K5 V.[2] The second object cannot be seen, but based on its calculated mass of 6.6 M,[2] it is too massive to be a neutron star and must therefore be a stellar-mass black hole.[4] At a distance of about roughly 3,300 light-years (1,000 parsecs) away, this would make A0620-00 the nearest black hole to the Solar System, closer than GRO J1655-40.[5] The two objects orbit each other every 7.75 hours.[4]

A0620-00 has undergone two X-ray outbreaks. The first one was in 1917.[6] The second time, in 1975, the burst was detected by the Ariel 5 satellite.[7] During that time, A0620-00 was the brightest X-ray point source.[4] It is now classified as an X-ray nova.[4]

The black hole in A0620-00 pulls matter from the K-type star into an accretion disk.[2] The accretion disk emits significant amounts of visible light and X-rays. Because the K-type star has been pulled into an ellipsoidal shape, the amount of surface area visible, and thus the apparent brightness changes from the Earth's perspective. A0620-00 also bears the variable star designation V616 Monocerotis.[3]

Stephen Hawking memorial broadcast

On 15th June 2018, a signal was transmitted from the Esa big radio antenna at Cebreros (77km West of Madrid, Spain), in memory of Stephen Hawking, who died on 14 March 2018, and his work on the physics of black holes. The broadcast will travel the 3457 light year distance at the speed of light and will arrive in the year 5475; this will be the first ever human interaction with a black hole.[8] 1A 0620-00 was chosen for this broadcast as it is the closest black hole to Earth.[9]

See also

References

  1. 1 2 3 4 "1A 0620-00". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 26 August 2017.
  2. 1 2 3 4 5 6 7 Cantrell, Andrew G.; Bailyn, Charles D.; Orosz, Jerome A.; McClintock, Jeffrey E.; Remillard, Ronald A.; Froning, Cynthia S.; Neilsen, Joseph; Gelino, Dawn M.; Gou, Lijun (2010). "The Inclination of the Soft X-Ray Transient A0620-00 and the Mass of its Black Hole". The Astrophysical Journal. 710 (2): 1127–1141. arXiv:1001.0261. Bibcode:2010ApJ...710.1127C. doi:10.1088/0004-637X/710/2/1127.
  3. 1 2 Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/gcvs. Originally published in: 2009yCat....102025S. 1. Bibcode:2009yCat....1.2025S.
  4. 1 2 3 4 5 6 7 8 McClintock, J. E.; Remillard, R. A. (1986). "The black hole binary A0620-00". Astrophysical Journal. 308: 110–122. Bibcode:1986ApJ...308..110M. doi:10.1086/164482.
  5. Foellmi, Cédric (2009). "What is the closest black hole to the Sun?". New Astronomy. 14 (8): 674–691. arXiv:0812.4232. Bibcode:2009NewA...14..674F. doi:10.1016/j.newast.2009.04.003.
  6. Eachus, L. J.; Wright, E. L.; Liller, W. (1976). "Optical observations of the recurrent nova associated with A0620-00 - 1917-1975". Astrophysical Journal. 2. 203: L17–L19. Bibcode:1976ApJ...203L..17E. doi:10.1086/182009.
  7. Elvis, M.; Page, C. G.; Pounds, K. A.; Ricketts, M. J.; Turner, M. J. L. (1975). "Discovery of powerful transient X-ray source A0620-00 with Ariel V Sky Survey Experiment". Nature. 257: 656, 657. Bibcode:1975Natur.257..656E. doi:10.1038/257656a0.
  8. Stephen Hawking. [Prof Hawking: A fitting way to go https://www.bbc.co.uk/news/uk-england-cambridgeshire-44500291 "Stephen Hawking memorial"] "BBC", 15th June 2018.
  9. Kelly, Guy; Davies, Gareth (15 June 2018). "Stephen Hawking laid to rest between graves of Sir Isaac Newton and Charles Darwin". The Telegraph. ISSN 0307-1235. Retrieved 16 June 2018.
  • "A0620-00". Black Hole Encyclopedia. StarDate. 12 February 2012.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.