The Outburst of HST-1 in the M87 Jet

  title={The Outburst of HST-1 in the M87 Jet},
  author={D. E. Harris and Chak-chung Cheung and J. A. Biretta and William B. Sparks and William Junor and Eric S. Perlman and A. S. Wilson},
  journal={The Astrophysical Journal},
  pages={211 - 218}
The X-ray intensity of knot HST-1, 0.″85 from the nucleus of the radio galaxy M87, has increased by more than a factor of 50 during the last 5 yr. The optical increase is similar, and our more limited radio data indicate a commensurate activity. We give the primary results of our Chandra X-Ray Observatory monitoring program and consider some of the implications of this extreme variability in a relativistic jet. We find that the data support a "modest beaming synchrotron" model as indicated in… 

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