NGC 4293

NGC 4293
Partial image of NGC 4293 taken by the Hubble Space Telescope
Observation data (J2000 epoch)
ConstellationComa Berenices
Right ascension12h 21m 12.891s[1]
Declination+18° 22′ 56.64″[1]
Redshift0.002977[2]
Heliocentric radial velocity893[3]
Distance54 Mly (16.5 Mpc)[4]
Group or clusterVirgo Cluster
Apparent magnitude (V)10.4[5]
Characteristics
Type(R)SB(s)0/a[6]
Apparent size (V)5.293′ × 1.800′[1]
Other designations
2MASX J12211289+1822566, IRAS 12186+1839, LEDA 39907, UGC 7405, UZC J122112.6+182256, Z 99-23, VCC 460.[7]

NGC 4293 is a lenticular galaxy in the northern constellation of Coma Berenices. It was discovered by English astronomer William Herschel on March 14, 1784, who described it as "large, extended, resolvable, 6 or 7′ long". This galaxy is positioned to the north-northwest of the star 11 Comae Berenices and is a member of the Virgo Cluster of galaxies.[5] It is assumed to lie at the same distance as the Virgo Cluster itself: around 54 million light years away.[4] The galaxy spans an apparent area of 5.3 × 3.1 arc minutes.[5]

The morphological classification of NGC 4293 is (R)SB(s)0/a, with the SB0/a indicating this has just distinguishable tightly wound spiral arms with a bar structure at the nucleus. An '(s)' notation means that this galaxy does not have a ring-like structure around the nucleus.[6][8] Star formation within NGC 4293 is only taking place within a confined region at the center of the galaxy.[9] The outer stellar disk of the galaxy appears disturbed, suggesting some form of gravitational interaction.[10]

This is a common type of active galaxy known as a LINER, which means that the optical spectrum is dominated by emission lines from gases in low energy ionization states. The activity may be the result of a supermassive black hole (SMBH) in the nucleus that is undergoing a low rate of matter accretion. The estimated mass of such an SMBH is 5.9×107 M⊙.[11] Radio emission from thermal activity has been detected from the proximity of this object.[12]

  1. ^ a b c Cite error: The named reference ApJ131_1163 was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference apj560_2_566 was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference Crook2007 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference MNRAS413_2_813 was invoked but never defined (see the help page).
  5. ^ a b c Cite error: The named reference omeara2011 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference vaucoulerus1991 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference keel2015 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference pasp2009 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference rmaa2006 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference chiaberge2005 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference aa451_1_71 was invoked but never defined (see the help page).