Centaurus A Composite Image Gallery
Centaurus A, or Cen A is a radio galaxy in the constellation Centaurus,
approximately 10 million light years from Earth. These images show Cen A as
viewed by four different types of telescopes.
You can view composited images by selecting the combinations you would like to
see from the pull down menu on the right and then clicking the "Get Composite"
button.
Cen A in the X-ray range of the
spectrum. The X-ray image shows a bright source in the nucleus of the
galaxy, which is probably due to a supermassive black hole. The bright jet
extending out from the nucleus to the upper left is due to explosive or highly
energetic activity around the black hole which ejects matter at high speeds from
the vicinity of the black hole.
Cen A in the optical range of the
spectrum. Optical image shows that Cen A is an elliptical galaxy with huge
dust lanes across the middle of the galaxy. This has led astronomers to speculate
that Cen A was the site of a merger between a small spiral galaxy and a large
elliptical galaxy several hundred million years ago. The optical radiation is
primarily from stars.
Cen A in the infrared range of the
spectrum. The infrared image gives a better view of the dust lanes, as
well as the brilliance of the central source. The infrared radiation is produced
by cool stars with temperatures of "only" a few thousand degrees Celsius, and by
dust that has been heated to a few hundred to a thousand degrees.
Cen A in the radio range of the
spectrum. The radio image shows striking jet-like structures that flare
out from the center of the galaxy. These structures have been traced well beyond
the galaxy out to distances of 600,000 years. The total length of the radio jet
shown here is about ten arc minutes, or about 30,000 light years in length. The
radio emission is produced by the synchrotron process, in which high-energy
electrons radiate as they spiral around the magnetic field of the galaxy.
