Fierce stellar black hole


Pick of the pics

A fierce stellar black hole

To get this X-ray image, to be published in Nature tomorrow, NASA’s Chandra satellite stared at a galaxy 13 million light-years away in the Sculptor Constellation for a total of 14 hours. The tartan pattern of pixels is a symptom of the great distance. A stellar black hole, or microquasar, seen location-wise in blue (X-rays of 2-8 keV), is throwing out two huge jets of hot gas reaching to the yellow-red hot-spots (X-rays of lesser energy). The contour lines are for emissions from hydrogen atoms measured by the Cerro Tololo Inter-American Observatory. Other observations by the European Southern Observatory help to confirm that we’re seeing an exceptionally massive and greedy microquasar shedding much of its energy in the form of long jets of hot gas. From one jet end to the other is about 300 parsecs or 1000 light-years – roughly the distance from the Solar System to the bright stars of Orion.

Nigel Calder comments: Apologies for two brief “Pick of the pics” in a row. I’ve been busy with writing unrelated to this blog.


Manfred W. Pakull, Roberto Soria and Christian Motch, “A 300 parsec long jet-inflated bubble around a powerful microquasar in the galaxy NGC 7793”, Nature, 466, pp. 209–212, 8 July 2010. The text of the paper is available here: