Space Science Reviews

, Volume 40, Issue 3–4, pp 675–679 | Cite as

EXOSAT observations of NGC 1399 and NGC 1404: Two elliptical galaxies in the center of the Fornax cluster

  • K. O. Mason
  • S. R. Rosen


Imaging X-ray observations of the Fornax cluster of galaxies centered on NGC 1399 and NGC 1404 are presented. NGC 1399 and NGC 1404, which are separated by about 10 arc minutes, are found to have an unusually high ratio of x-ray to optical flux. We consider the possibility that the x-radiation is produced by hot gas in the cores of the galaxies. Weak X-ray emission is also detected from a point almost exactly mid-way between NGC 1399 and NGC 1404. The combined emission from the galaxies is insufficient by over an order of magnitude to account for the the low-energy X-ray emission detected from this region by the HEAO-l satellite. It is suggested that the bulk of the HEAO-1 source is diffuse gas associated with the cluster as a whole, rather than individual galaxies.


High Ratio Elliptical Galaxy Individual Galaxy Optical Flux Fornax Cluster 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© D. Reidel Publishing Company 1985

Authors and Affiliations

  • K. O. Mason
    • 1
  • S. R. Rosen
    • 1
  1. 1.Mullard Space Science LaboratoryDorkingUK

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