Our Milky Way
Formation of Stars
The large mosaic of 15 Hubble images showing the central part of the Orion complex is one of the most detailed images of a star-forming region ever made. It shows a very young star cluster blowing a 'bubble' in its remnant parent cloud of glowing gas so that the stars start to be seen in visible light - like the smoke in a forest fire being driven away by the heat. Hubble's high resolution has been crucial in the investigation of the dust discs, dubbed proplyds, around the newly born stars in the Orion Nebula. The 'proplyds' may very well be young planetary systems in the early phases of their creation. The details that are revealed are far finer than than can be seen with ground-based instruments and, thanks to Hubble, we today have visual proof that dusty discs around young stars are common.
Since star birth always seems to take place in dusty environments, Hubble's infrared capabilities have been a very important factor. The infrared instrument NICMOS can peer through much of the dust and reveal the complex processes taking place in star-forming regions. Otherwise invisible close double and multiple stars have been discovered, as well as faint substellar brown dwarf companions. With NICMOS and its visual counterpart WFPC2, Hubble has observed giant jets of material spewing out from infant stars surrounded by large discs of dust, giving a fantastic view into the dramatic first steps in the lives of newly born stars.
Hans Zinnecker
Astrophysicist, Astrophysical Institute Potsdam
"To astronomers and laymen alike the topic of star formation has always been a particularly appealing one. Important clues about our genesis lie hidden behind the veil of the dusty, and often very beautiful, star- forming molecular clouds. Our Earth and the Solar System were born 4.6 billion years ago and our knowledge of the event is sparse. Astronomers turn their eyes to the birth of other stars and stellar systems in neighbouring stellar 'maternity wards' and use these as a time machine to see a replay of the events that created our own Solar System."
"Hubble has had a major impact in two areas in the field of star formation. Firstly it has studied the formation of stars like our Sun and has literally seen dusty discs which may end up as planetary systems around those stars. Secondly Hubble has made an impact in the area one could call 'cosmological star formation', that is, the formation of stars all over the Universe. The Hubble Deep Field North for instance opened up the box and allowed us to follow the history of star formation through the entire Universe and in this way enabled us to study the 'cosmic evolution' of the stars."
 |
Stellar Evolution |
Last Update: 03 Jul 2003