Astronomy Picture of the Day Index - Stars: Stellar Nurseries

APOD: 2005 April 24 - M16: Stars from the Eagle's EGGs
Explanation: Newborn stars are forming in the Eagle Nebula. This image, taken with the Hubble Space Telescope in 1995, shows evaporating gaseous globules (EGGs) emerging from pillars of molecular hydrogen gas and dust. The giant pillars are light years in length and are so dense that interior gas contracts gravitationally to form stars. At each pillars' end, the intense radiation of bright young stars causes low density material to boil away, leaving stellar nurseries of dense EGGs exposed. The Eagle Nebula, associated with the open star cluster M16, lies about 7000 light years away.

APOD: 1999 June 4 - NGC 3603: From Beginning To End
Explanation: >From beginning to end, different stages of a star's life appear in this exciting Hubble Space Telescope picture of the environs of galactic emission nebula NGC 3603. For the beginning, eye-catching "pillars" of glowing hydrogen at the right signal newborn stars emerging from their dense, gaseous, nurseries. Less noticeable, dark clouds or "Bok globules" at the top right corner are likely part of a still earlier stage, prior to their collapse to form stars. At picture centre lies a cluster of bright hot blue stars whose strong winds and ultraviolet radiation have cleared away nearby material. Massive and young, they will soon exhaust their nuclear fuel. Nearing the end of its life, the bright supergiant star Sher 25 is seen above and left of the cluster, surrounded by a glowing ring and flanked by ejected blobs of gas. The ring structure is reminiscent of Supernova 1987a and Sher 25 itself may be only a few thousand years from its own devastating finale. But what about planets? Check out the two teardrop-shaped objects below the cluster toward the bottom of the picture. Although larger, these emission nebulae are similar to suspected proto-planetary disks (proplyds) encompassing stars in the Orion Nebula.

APOD: 2004 July 13 - Orion Nebula in Oxygen, Hydrogen, and Sulfur
Explanation: The Great Nebula in Orion, an immense, nearby starbirth region, is arguably the most famous of all astronomical nebulae. The Orion Nebula, also known as M42, is shown above through ultraviolet and blue filters augmented with three exact colours specifically emitted by hydrogen, oxygen, and sulphur. In addition to housing a bright open cluster of stars known as the Trapezium, the Orion Nebula contains many stellar nurseries. These nurseries contain glowing gas, hot young stars, proplyds, and stellar jets spewing material at high speeds. Many of the filamentary structures visible in this image are actually shock waves - fronts where fast moving material encounters slow moving gas. The Orion Nebula spans about 40 light years and is located about 1500 light years away in the same spiral arm of our Galaxy as the Sun.