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Massive stars in the Carina Nebula

auteur: Nasa/Esa/Novapix

référence: a-neb33-72111

Image Size 300 DPI: 32 * 33 cm

The image shows a pair of colossal stars, WR 25 and Tr16-244, located within the open cluster Trumpler 16. This cluster is embedded within the Carina Nebula, an immense cauldron of gas and dust that lies approximately 7500 light-years from Earth in the constellation of Carina, the Keel.
The Carina Nebula contains several ultra-hot stars, including these two star systems and the famous blue star Eta Carinae, which has the highest luminosity yet confirmed. As well as producing incredible amounts of heat, these stars are also very bright, emitting most of their radiation in the ultraviolet and appearing blue in colour. They are so powerful that they burn through their hydrogen fuel source faster than other types of stars, leading to a "live fast, die young" lifestyle. WR 25 is the brightest, situated near the centre of the image. The neighbouring Tr16-244 is the third brightest, just to the upper left of WR 25. The second brightest, to the left of WR 25, is a low mass star located much closer to the Earth than the Carina Nebula. Stars like WR 25 and Tr16-244 are relatively rare compared to other, cooler types. WR 25 is likely to be the most massive and interesting of the two. It is composed of at least two stars. The more massive is a Wolf-Rayet star and may weigh more than 50 times the mass of our Sun. It is losing mass rapidly through powerful stellar winds that have expelled the majority of its outermost hydrogen-rich layers, while its more mundane binary companion is probably about half as massive as the Wolf-Rayet star, and orbits around it once every 208 days. Hubble observations have revealed that the Tr16-244 system is actually a triple star. Two of the stars are so close to each other that they look like a single object. The third star takes tens or hundreds of thousands of years to orbit the other two. The brightness and proximity of the components of such massive double and triple stars makes it particularly challenging to discover the properties of massive stars. WR 25 and Tr16-244 are the likely sources of radiation that is causing a giant gas globule within the Carina Nebula to slowly evaporate away into space, while possibly inducing the formation of new stars within it.

Keywords for this photo:

2008 - ASTRONOMY - CARINA - HST - HUBBLE SPACE TELESCOPE - MASSIVE STAR - NEBULA - NGC 3372 - OPEN CLUSTER - SOUTHERN HEMISPHERE - STAR - STAR CLUSTER - TR16-244 - TRUMPLER 16 - WOLF-RAYET - WR 25 -