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Cygnus A: Radio Galaxy

Type of Object:  Cygnus A is a powerful radio galaxy.  At 1420 MHz it looks like a double source and is thought to be an active galaxy.  It’s energy output is equivalent to that of 10 billion Crab Nebulas!

Distance: 700 Million light years
Size: About 500,000 light years across
Coordinates (Epoch J2000):
         Right Ascension:         
19 59 28.4
         Declination:                  +40 44 01.0

Other Names:

Radio Brightness at 1420 MHz (21 cm): 1260 Jy

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Location on the sky: The active galaxy Cyg A is located near the star delta Cygni in the constellation Cygnus. The location of Cyg A is shown in the figure to the right.

Images shown below, at different wavelengths, cover a
0.5 degree x 0.5 degree area of the sky centered on the nebula.  The images are taken from  the SKYVIEW Virtual Observatory maintained under NASA ADP Grant NAS5-32068 with P.I.
Thomas A. McGlynn under the auspices of the High Energy Astrophysics Science  Archive Research Center (HEASARC) at the GSFC Laboratory for High Energy Astrophysics. SKYVIEW contains catalogs and surveys from x-ray to radio observations. The site is located at http://skyview.gsfc.nasa.gov/

Visible image from the digitized Palomar Sky Survey E plates.  Doesn’t show much visible nebulosity.

Far-Infrared Image at 100 microns taken by the Infrared Astronomical Satellite (IRAS) Survey. Shows the dust component of the nebulosity

Image taken at the radio emission of neutral hydrogen at 1420 MHz by the NRAO VLA Sky Survey.  Shows the double gas component of the galaxy.

Image taken at the radio emission frequency of 4850 MHz.  Image shows the gas component, but not the double structure seen in the 1420 MHz image. Image is from a Green Bank survey from 0° to +75° declination).

[Orion Nebula] [crab_nebula] [W3] [cas_a] [cygnus_a] [her_a] [vir_a] [galactic_center] [sgp] [ngp]