World Library  
Flag as Inappropriate
Email this Article

Ngc 3115

Article Id: WHEBN0000970666
Reproduction Date:

Title: Ngc 3115  
Author: World Heritage Encyclopedia
Language: English
Subject: Herschel 400 Catalogue, Caldwell catalogue, NGC 3132, NGC 3242, NGC 3195
Collection:
Publisher: World Heritage Encyclopedia
Publication
Date:
 

Ngc 3115

NGC 3115
Composite image of NGC 3115 from the Chandra X-ray Observatory and the Very Large Telescope
Observation data (J2000 epoch)
Constellation Sextans
Right ascension 10h 05m 14.0s[1]
Declination −7° 43′ 07″[1]
Redshift 663 ± 4 km/s[1]
Distance 31.6 ± 1.3 Mly (9.7 ± 0.4 Mpc)[2]
Type S0[1]
Apparent dimensions (V) 7′.2 × 2′.5[1]
Apparent magnitude (V) 9.9[1]
Other designations
Spindle Galaxy, UGCA 199, PGC 29265,[1] Caldwell 53

NGC 3115 (also called the Spindle Galaxy or Caldwell 53) is a field lenticular (S0) galaxy in the constellation Sextans. The galaxy was discovered by William Herschel on February 22, 1787.[3][4] At about 32 million light-years away from us it is several times bigger than our Milky Way. It is a lenticular (S0) galaxy because it contains a disk and a central bulge of stars, but without a detectable spiral pattern. NGC 3115 is seen almost exactly edge-on, but was nevertheless mis-classified as elliptical. There is some speculation that NGC 3115, in its youth, was a quasar.

Contents

  • Star formation 1
  • Black hole 2
  • See also 3
  • References 4
  • External links 5

Star formation

NGC 3115 has consumed most of the gas of its youthful accretion disk. It has very little gas and dust left that would trigger new star formation. The vast majority of its component stars are very old.

Black hole

In 1992 John Kormendy of the University of Hawaii and Douglas Richstone of the University of Michigan announced what was observed to be a supermassive black hole in the galaxy.[5] Based on orbital velocities of the stars in its core, the central black hole has mass measured to be approximately one billion solar masses (M). The galaxy appears to have mostly old stars and little or no activity. The growth of its black hole has also stopped.

In 2011, NASA's Chandra X-ray Observatory examined the black hole at the center of the large galaxy. A flow of hot gas toward the supermassive black hole has been imaged, making this the first time clear evidence for such a flow has been observed in any black hole. As gas flows toward the black hole, it becomes hotter and brighter. The researchers found the rise in gas temperature begins at about 700 light years from the black hole, giving the location of the Bondi radius. This suggests that the black hole in the center of NGC 3115 has a mass of about two billion M, supporting previous results from optical observations. This would make NGC 3115 the nearest billion-solar-mass black hole to Earth.

See also

  • NGC 5866another lenticular galaxy sometimes referred to as the Spindle Galaxy

References

  1. ^ a b c d e f g "NASA/IPAC Extragalactic Database". Results for NGC 3115. Retrieved October 12, 2006. 
  2. ^ J. L. Tonry; A. Dressler; J. P. Blakeslee; E. A. Ajhar; et al. (2001). "The SBF Survey of Galaxy Distances. IV. SBF Magnitudes, Colors, and Distances". Astrophysical Journal 546 (2): 681–693.  
  3. ^ O'Meara, Stephen James (2002). The Caldwell Objects. Cambridge: Cambridge University Press. p. 211.  
  4. ^ Materne, J. (April 1979). "The structure of nearby groups of galaxies - Quantitative membership probabilities". Astronomy and Astrophysics 74 (2): 235–243.  
  5. ^ Kormendy, J. and Richstone, D. "Evidence for a supermassive black hole in NGC 3115", Astrophysical Journal, Part 1, vol. 393, no. 2, July 10, 1992, p. 559-578.

External links

  • Chandra Press Release
  • SEDS: NGC 3115
  • NGC 3115 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images

This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 



Copyright © World Library Foundation. All rights reserved. eBooks from Hawaii eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.