Triggering the Birth of a New Generation of Stars

The birth of a new generation of stars is often triggered by the death of old stars. Both events are accompanied by much violence, as illustrated here by two examples -- the explosive death of a massive star and high-speed jets of gas from a young star.

The ejecta of a supernova explosion, which marks the death of a massive star, plows through the dark, dense gas and dust of an interstellar cloud. The blue-green filaments in the above image correspond to the material ejected by the supernova at speeds of several million miles per hour. The reddish filaments are cloud material that has been compressed and heated by the explosion. It is compressions such as these that trigger the formation of new generations of stars. The explosion of this supernova should have been visible on Earth around 1000 B.C.

The jet shown in this image burrowed through the dust of the cloud and now travels into interstellar space at more than half-a-million miles per hour. Narrowly focused, high-speed jets like this one are common phenomena in star birth. How they arise and how they get focused are open questions.