Credit: NRAO and NASA's Goddard Space Flight Center
Jet Taking Off
Contrary to popular wisdom, you can escape from a black hole. In fact, evidence of narrow escapes from supermassive black holes in the centers of active galaxies can be commonly seen. The escaping material rides away on confined beams of particles fired from off the black hole. These so-called "radio jets" (since they are best detected by the radio radiation they emit) can extend for hundreds of thousands of light-years, somehow remaining confined in a narrow beam for that entire distance. Closer to home, similar jets have been found to be associated with smaller, stellar-mass black holes found circling normal stars in the Milky Way and in other nearby galaxies. But how material is able to escape from the voracious maw of a black hole is a puzzle. Thanks to intense study of one black hole system call H1743-322, we've now found an important piece of this puzzle. New observations with the Very Long Baseline Array of radio telescopes, coupled with high energy observations from the Rossi X-ray Timing Explorer, have given astronomers their best-ever look at how material being accreted by a black hole can make its timely escape along a radio jet. The radio emission from the system as seen by the VLBA over the period from May 28, 2009 to June 6, 2009 is shown in the top panel, while X-ray timing observations from RXTE are shown in the middle panel. The X-ray data show evidence of "quasi-periodic oscillations", a signal believed to originate in a bright blob of gas on a death spiral towards the event horizon of the black hole. Comparison of the VLBA radio observations with the X-ray timing signals indicate that a jet of material was fired from the system at just about the same time as the signals from the bright accreting blobs disappeared, as shown in the artist conception in the bottom panel. This may suggest that the spiralling material seen by RXTE entered a region of instability in the space-time continuum near the black hole, and was shot away in the form of the radio jet seen by the VLBA.
Published: January 16, 2012
HEA Dictionary * Archive
* Search HEAPOW
* Other Languages
* HEAPOW on Facebook
* Download all Images
Each week the HEASARC
brings you new, exciting and beautiful images from X-ray and Gamma ray
astronomy. Check back each week and be sure to check out the HEAPOW archive!
Page Author: Dr. Michael F. Corcoran
Last modified Thursday, 03-May-2012 14:23:53 EDT