Astronomy:NGC 6993

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NGC 6993
NGC 6993 imaged by Pan-STARRS
Observation data (J2000 epoch)
ConstellationCapricornus
Right ascension 20h 53m 54.0499s[1]
Declination−25° 28′ 20.920″[1]
Redshift0.020277±0.00000900[1]
Helio radial velocity1,733±9 km/s[1]
Distance280.2 ± 19.6 Mly (85.91 ± 6.02 Mpc)[1]
Apparent magnitude (V)14.5[1]
Characteristics
TypeSB(r)cd[1]
Size~204,500 ly (62.69 kpc) (estimated)[1]
Apparent size (V)1.3′ × 1.1′[1]
Other designations
ESO 529- G 011, IRAS 20509-2539, MCG-04-49-007, PGC 65671[1]

NGC 6993 is a large barred spiral galaxy in the constellation of Capricornus. Its velocity with respect to the cosmic microwave background is 5,824±18 km/s, which corresponds to a Hubble distance of 280.2 ± 19.6 Mly (85.91 ± 6.02 Mpc).[1] It was discovered by American astronomer Francis Leavenworth on 8 July 1885.[2]

NGC 6993 has a possible active galactic nucleus, i.e. it has a compact region at the center of a galaxy that emits a significant amount of energy across the electromagnetic spectrum, with characteristics indicating that this luminosity is not produced by the stars.[3][4]

Galaxy group

NGC 6993 is a member of a small group of three galaxies known as [CHM2007] LDC 1426. The other two galaxies are MCG -04-49-005 and MCG -04-49-004.[5][6]

Supernova

One Supernova has been observed in NGC 6993:

  • SN 2020pvb (Type IIn, mag. 21.04) was discovered by Pan-STARRS on 18 July 2020.[7] This supernova was initially detected during a pre-explosion outburst, with the actual supernova occurring several weeks later.[8] Spectral signatures and a plateau-like light curve led scientists to classify SN 2020pvb as Type IIn-P, similar to SN 1994W, SN 2009kn, and SN 2011ht.[8]

See also

References

  1. 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 "Results for object NGC 6993". NASA and Caltech. https://ned.ipac.caltech.edu/byname?objname=NGC+6993. 
  2. Seligman, Courtney. "New General Catalogue Objects: NGC 6993". https://cseligman.com/text/atlas/ngc69a.htm#6993. 
  3. Asmus, D.; Greenwell, C. L.; Gandhi, P.; Boorman, P. G.; Aird, J.; Alexander, D. M.; Assef, R. J.; Baldi, R. D. et al. (2020). "Local AGN survey (LASr): I. Galaxy sample, infrared colour selection, and predictions for AGN within 100 MPC". Monthly Notices of the Royal Astronomical Society 494 (2): 1784. doi:10.1093/mnras/staa766. Bibcode2020MNRAS.494.1784A. 
  4. "NGC 6993". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=NGC+6993. 
  5. Crook, Aidan C.; Huchra, John P.; Martimbeau, Nathalie; Masters, Karen L.; Jarrett, Tom; Macri, Lucas M. (2007). "Groups of Galaxies in the Two Micron All Sky Redshift Survey". The Astrophysical Journal 655 (2): 790. doi:10.1086/510201. Bibcode2007ApJ...655..790C. 
  6. "[CHM2007 LDC 1426"]. SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=%5BCHM2007%5D+LDC+1426. 
  7. "SN 2020pvb". IAU. https://www.wis-tns.org/object/2020pvb. 
  8. 8.0 8.1 Elias-Rosa, N. et al. (2024). "SN 2020pvb: A Type IIn-P supernova with a precursor outburst". Astronomy & Astrophysics 686: A13. doi:10.1051/0004-6361/202348790. https://doi.org/10.1051/0004-6361/202348790. 

Coordinates: Sky map 20h 53m 54.0499s, −25° 28′ 20.920″