Image Credit: X-ray: NASA/CXC/SAO; Optical: NASA/STScI; Radio: NSF/NRAO/AUI/VLA
Last month, to kickstart the
International Year of Light (IYL), NASA released this stunning remastered image of Cygnus A: a galaxy that can be found approximately 600 million light-years from Earth, in a constellation of the same name (Cygnus). While it truly is the most stunning image taken to date, it's also pretty educational.
You see,
Cygnus A has a reputation for being one of the most active radio galaxies in the local universe. When viewed from non-optical wavelengths, one can see the various mechanisms secretly at work. Take x-ray wavelengths, for instance. In this color-composite, x-ray activity — pictured in blue — overpowers pretty much everything else; sources are believed to be binary star systems, supernovae, gamma-ray bursts, and, of course, a supermassive black hole hiding out in the galaxy's central core.
Pinkish-red is also a prominent color in this specific image. It maps the galaxy's emission at the radio portion of the electromagnetic spectrum. Specifically, it shows the two large jets emanating from the poles of Cygnus A's central black hole; this heavyweight sends high-energy particles, traveling at relativistic speeds (speeds that are comparable to that of light), more than 300,000 light-years past the central core.
Radio data, which was compiled by NSF's 'Very Large Array,' also reveals the location of several
galactic "hot spots." Simply put, these are regions in which superheated gas meets the cooler, more dense material outside the galaxy's walls. The shock of it jolts the jets to a screeching halt.
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