(Credit: figure and text from EXOSAT slide set)
The hard X-ray light curve of the BL Lac object PKS 2155-304, seen with
the medium energy detectors on board EXOSAT. The variability is so rapid
(a factor of 10 in 6 hours) and the luminosity so high that relativistic
bulk motions, nearly along the line of sight, are probably occurring.
This is direct evidence of relativistic beaming.
Additions or Comments:
Have we left anything out? Is there something you would like to have added
to this page (a link to your own group's research page, for example...)?
By Mission |
Cataclysmic Variables |
X-ray Binaries |
Supernova Remnants & Planetary Nebulae |
Active Galactic Nuclei |
Clusters and Groups of Galaxies |
X-ray/gamma-ray Background & Deep Fields |
Solar System Objects |
Gamma Ray Bursts
HEASARC Home |
Last modified: Thursday, 26-Jun-2003 13:48:46 EDT