Clear New View of a Classic Spiral

Clear New View of a Classic Spiral (5/19/10)

The galaxy Messier 83 is located about 15 million light-years away in the constellation of Hydra (the Sea Serpent). It spans over 40 000 light-years, only 40 percent the size of the Milky Way, but in many ways is quite similar to our home galaxy, both in its spiral shape and the presence of a bar of stars across its centre. Messier 83 is famous among astronomers for its many supernovae: vast explosions that end the lives of some stars. Over the last century, six supernovae have been observed in Messier 83 — a record number that is matched by only one other galaxy. Even without supernovae, Messier 83 is one of the brightest nearby galaxies, visible using just binoculars.

Messier 83 has been observed in the infrared part of the spectrum using HAWK-I, a powerful camera on ESO’s Very Large Telescope (VLT). When viewed in infrared light most of the obscuring dust that hides much of Messier 83 becomes transparent. The brightly lit gas around hot young stars in the spiral arms is also less prominent in infrared pictures. As a result much more of the structure of the galaxy and the vast hordes of its constituent stars can be seen. This clear view is important for astronomers looking for clusters of young stars, especially those hidden in dusty regions of the galaxy.

M83 – click for 1600×1200 image

Another view of M83: here

More: here