M 83 is often called the "Southern Pinwheel" because of its
long, distinct spiral arms (the other "Pinwheel" being M 101).
The nucleus and central "bar" contain a population of older, yellow
stars. Along the arms of the galaxy are knots of red hydrogen nebula
where new stars are forming, and blue knots of young star clusters.

M 83 is 15 million light years away in the constellation Hydra.

Image data:
Telescope: Planewave 17"
Camera: SBIG STXL-11002
Exposure: Red, Green, Blue: 20 minutes x 15 each
Luminance: 20 minutes x 21
Hydroden-alpha: 30 minutes x 3
(total exposure = 23 1/2 hours)
Location: Heaven's Mirror Observatory, New South Wales, Australia