M87: A Misaligned BL Lacertae Object?

  title={M87: A Misaligned BL Lacertae Object?},
  author={Zlatan I. Tsvetanov and George F. Hartig and Holland C. Ford and Michael A. Dopita and Gerard A. Kriss and Yichuan C. Pei and Linda Lou Dressel and Richard J. Harms},
  journal={The Astrophysical Journal Letters},
  pages={L83 - L86}
The nuclear region of M87 was observed with the Faint Object Spectrograph (FOS) on the Hubble Space Telescope (HST) at six epochs, spanning 18 months, after the HST image quality was improved with the deployment of the corrective optics (COSTAR) in 1993 December. From the FOS target acquisition data, we have established that the flux from the optical nucleus of M87 varies by a factor of ~2 on timescales of ~2.5 months and by as much as 25% over 3 weeks and remains unchanged (≲2.5%) on… 

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