Starburst Galaxy
A starburst galaxy ( Starburst English. About "star burst") is a galaxy in which many more new stars are formed, as is typical for a galaxy of this size. The delimitation to normal galaxies is not sharply defined; Usually, starburst galaxies are only known as galaxies whose star formation rate is so high that it cannot be sustained for billions of years from the available gas supply.
The term starburst is sometimes also applied to parts of galaxies with spatially limited active star formation . However, it loses its meaning on the smaller scale of star formation regions , as they are also common in normal spiral galaxies .
The young stars of a starburst emit strongly in the ultraviolet range of electromagnetic radiation and ionize large parts of the interstellar matter in the galaxy. However, many starburst galaxies contain so much dust that most of the luminosity of their young stars is absorbed by the dust and over 90% of their total energy is re-emitted in the far infrared . Starbursts of various properties were therefore discovered in sky surveys in the ultraviolet (e.g. by Benjamin Markarjan and co-workers in the 1960s) or in the far infrared (especially by IRAS ). Many infrared galaxies are starburst galaxies. A well-known example is Messier 82 .
Interaction and merging of galaxies can stimulate starbursts, as can gas flows along the bars of barred spiral galaxies . Studies of starburst galaxies deal, among other things, with the mass distribution of the newly formed stars, the compact, massive star clusters formed in starbursts and with the feedback to the interstellar and intergalactic medium caused by radiation and stellar winds . By stellar winds and supernova explosions in a starburst galaxy part can their interstellar medium are heated so much that they in a Super Wind leaves.
The closest starburst galaxy to Earth is IC 10 .
Web links
- ESO: First detection of CH + molecules in distant starburst galaxies August 30, 2017
literature
- A. Unsöld, B. Baschek: The New Cosmos Introduction to Astronomy and Astrophysics . 7th revised and expanded edition. Springer Verlag, Berlin 2004, ISBN 978-3-540-42177-1 .
- Peter Schneider: Introduction to Extragalactic Astronomy and Cosmology . 1st edition. Springer Verlag, Berlin 2006, ISBN 978-3-540-25832-2 .