Black Holes Found to be Green

Astronomers using NASA's Chandra X-ray Observatory announce a fundamental discovery about black holes.
Audio of the event will be streamed live on the Web at:


  • Dr. Steve Allen, Assistant Professor of Physics, Stanford University and the Stanford Linear Accelerator Center

  • Dr. Chris Reynolds, Associate Professor of Astronomy at the University of Maryland, College Park

  • Dr. Kim Weaver, Associate Director for Science of the Exploration of the Universe Division, NASA's Goddard Space Flight Center


  1. Fuel for the Black Hole Engine (Illustration):
    labeled: (jpg | tif)
    unlabeled: (jpg | tif)

  2. Close-up of Black Hole Engine (Illustration): (jpg | tif)

  3. Centaurus, Chandra X-ray:
    labeled: jpeg
    unlabeled: jpeg | tiff

  4. Giant Cavities Caused by Black Hole Engine (Illustration): (jpg | tif)

  5. Black Hole Accretion disk/jet animation: mpg | mov

    Supplementary Figures

  1. Centaurus, X-ray/Radio/IR composite: jpeg | tiff

  2. 9-panel of galaxies, Chandra X-ray: jpeg | Labeled Version: jpeg

  3. Centaurus, X-ray/Radio: jpeg | tif


  • Full Author List: Steve Allen (KIPAC, Stanford), Robert Dunn (Cambridge), Andy Fabian (Cambridge), Greg Taylor (Univ. of Mexico), Chris Reynolds (Univ. of Maryland).
galaxy distance (light years) black hole mass (solar masses)
NGC 507 232 million 0.8 billion
NGC 4374 55 million 0.6 billion
NGC 4472 55 million 0.7 billion
NGC 4486 55 million 3.0 billion
NGC 4552 55 million 0.4 billion
NGC 4636 55 million 0.2 billion
NGC 4696 146 million 0.4 billion
NGC 5846 80 million 0.4 billion
NGC 6166 442 million 0.8 billion


Instant Replay Plus Information:
An instant replay of the media telecon will be available after the end of the telecon. Call: 800-219-6387 (toll free). This service will be available until 10:59 PM (CT) MAY-01-06.

NASA-TV Video File:
A video file about the discovery will air on NASA TV on April 24. NASA TV is carried on an MPEG-2 digital signal accessed via satellite AMC-6, at 72 degrees west longitude, transponder 17C, 4040 MHz, vertical polarization. It's available in Alaska and Hawaii on AMC-7 at 137 degrees west longitude, transponder 18C, at 4060 MHz, horizontal polarization.