Messier 81

Messier 81
The HST's view of M81, with its open star clusters, globular star clusters, and regions of fluorescent gas.
Observation data (J2000 epoch)
ConstellationUrsa Major[1]
Right ascension09h 55m 33.2s[2]
Declination+69° 3′ 55″[2]
Redshift−0.000113
Heliocentric radial velocity−34
Galactocentric velocity73
Distance11.8 Mly (3.6 Mpc)
Apparent magnitude (V)6.94[3][4]
Characteristics
TypeSA(s)ab,[2] LINER[2]
Size29.44 kiloparsecs (96,000 light-years)
(diameter; 25.0 mag/arcsec2 B-band isophote)[2][5]
Apparent size (V)26.9 × 14.1 moa[2]
Other designations
NGC 3031, UGC 5318, MCG+12-10-010, PGC 28630, Bode's Galaxy[3]
Preview warning: Page using Template:Infobox galaxy with unknown parameter "z_err"
Preview warning: Page using Template:Infobox galaxy with unknown parameter "gv_err"
Preview warning: Page using Template:Infobox galaxy with unknown parameter "dist_err"
Preview warning: Page using Template:Infobox galaxy with unknown parameter "hrv_err"

Messier 81 (also known as NGC 3031 or Bode's Galaxy) is a grand design spiral galaxy about 12 million light-years away in the constellation Ursa Major. It has a D25 isophotal diameter of 29.44 kiloparsecs (96,000 light-years).[2][5] Because of its relative proximity to the Milky Way galaxy, large size, and active galactic nucleus (which harbors a 70 million M[6] supermassive black hole), Messier 81 has been studied extensively by professional astronomers. The galaxy's large size and relatively high brightness also makes it a popular target for amateur astronomers.[7] In late February 2022, astronomers reported that M81 may be the source of FRB 20200120E, a repeating fast radio burst.[8][9]

  1. ^ Dreyer, J. L. E. (1988). Sinnott, R. W. (ed.). The Complete New General Catalogue and Index Catalogue of Nebulae and Star Clusters. Sky Publishing Corporation / Cambridge University Press. ISBN 978-0-933346-51-2.
  2. ^ a b c d e f g h i j "NASA/IPAC Extragalactic Database". Results for Messier 081. Retrieved 6 November 2022.
  3. ^ a b "M 81". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 28 November 2009.
  4. ^ Armando, Gil de Paz; Boissier, Samuel; Madore, Barry F.; Seibert, Mark; Joe, Young H.; Boselli, Alessandro; Wyder, Ted K.; Thilker, David; Bianchi, Luciana; Rey, Soo-Chang; Rich, R. Michael; Barlow, Tom A.; Conrow, Tim; Forster, Karl; Friedman, Peter G.; Martin, D. Christopher; Morrissey, Patrick; Neff, Susan G.; Schiminovich, David; Small, Todd; Donas, José; Heckman, Timothy M.; Lee, Young-Wook; Milliard, Bruno; Szalay, Alex S.; Yi, Sukyoung (2007). "The GALEX Ultraviolet Atlas of Nearby Galaxies". Astrophysical Journal. 173 (2): 185–255. arXiv:astro-ph/0606440. Bibcode:2007ApJS..173..185G. doi:10.1086/516636. S2CID 119085482.
  5. ^ a b De Vaucouleurs, Gerard; De Vaucouleurs, Antoinette; Corwin, Herold G.; Buta, Ronald J.; Paturel, Georges; Fouque, Pascal (1991). Third Reference Catalogue of Bright Galaxies. Bibcode:1991rc3..book.....D.
  6. ^ Devereux, N.; Ford, H.; Tsvetanov, Z.; Jocoby, J. (2003). "STIS Spectroscopy of the Central 10 Parsecs of M81: Evidence for a Massive Black Hole". Astronomical Journal. 125 (3): 1226–1235. Bibcode:2003AJ....125.1226D. doi:10.1086/367595. S2CID 121093306.
  7. ^ O'Meara, S. J. (1998). The Messier Objects. Cambridge University Press. ISBN 978-0-521-55332-2.
  8. ^ Cite error: The named reference SA-20220223 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference NAT-20220223 was invoked but never defined (see the help page).