The Herschel Space Observatory has uncovered a weird ring of dusty material while obtaining one of the sharpest scans to date of a huge cloud of gas and dust, called NGC 7538.
The gigantic ring structure is situated at the center-top of this image.
The odd ovoid possesses the mass of 500 suns, with its long axis spanning about 35 light-years and its short axis about 25 light-years.
Astronomers often see ring and bubble-like structures in cosmic dust clouds.
The strong winds cast out by the most massive stars, called O-type stars, can generate these expanding puffs, as can their explosive deaths as supernovas but no energetic source or remnant of a deceased O-type star, such as a neutron star, is apparent within the center of the ring.
It is possible that a big star blew the bubble and, because stars are all in motion, subsequently left the scene, escaping detection.
Early in the star-formation process, these clumps remain quite cold, just a few tens of degrees above absolute zero.
At these temperatures, the clumps emit the bulk of their radiation in the low-energy, submillimeter and infrared light that Herschel was specifically designed to detect.
Finding the mysterious ring came as an unexpected bonus during the Herschel observing run.
The red colours are 250-micron observations obtained from Herschel's Spectral and Photometric Imaging Receiver (SPIRE) instrument.
Posts
No comments:
Post a Comment