domingo, 31 de julio de 2011

[Image] The Unbearable Beauty of the Milky Way's Hidden Star-Birth Regions

Stars-milky-way-cfht

Astronomers Bania and Loren Anderson of the Astrophysical Laboratory of Marseille in France have discovered about 450 hidden stellar nurseries in the Milky Way where rare colossal stars many times bigger than the sun are being born. The discovery doubles the number of known sites in the northern reaches of the galaxy where massive stars are born, said Tom Bania of Boston University, who estimats that there could be another 4,000 or so fainter massive-star birth regions awaiting discovery throughout the galaxy.



Locating regions that form massive stars is like "putting pins on a map" to reveal the full structure of the Milky Way's spiral arms, according to  Patrick Thaddeus of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. Gas and dust make the regions impossible to see in visible light, so astronomers have to resort to other wavelengths to trace them out.

The researchers inferred the existence of the star birth sites by observing them in both infrared and radio wavelengths using NASA's Spitzer Space Telescope and ground-based observatories in West Virginia and New Mexico that were able to detect the effects on surrounding hydrogen gas of the intense ultraviolet light emitted by newborn massive stars.

The new-found regions could provide new information about the chemical composition and evolution of the Milky Way. Massive stars are likely to die in supernova explosions seeding nearby regions of space with the building blocks of solar systems and, ulltimately, life.



Mwspitzer

Provided by The Daily Galaxy