Astrophysicists 'weigh' galaxy's most massive star

Sep 19, 2008

Theoretical models of stellar formation propose the existence of very massive stars that can attain up to 150 times the mass of our Sun.

Until very recently, however, no scientist had discovered a star of more than 83 solar masses. Now an international team of astrophysicists, led by Université de Montréal researchers from the Centre de recherche en astrophysique du Québec (CRAQ), has found and "weighed" the most massive star to date.

Olivier Schnurr, Jules Casoli and André-Nicolas Chené, all graduates of the Université de Montréal, and professors Anthony F. J. Moffat and Nicole St-Louis, successfully "weighed" a star of a binary system with a mass 116 times greater than that of the Sun, waltzing with a companion of 89 solar masses, doubly beating the previous record and breaking the symbolic barrier of 100 solar masses for the first time.

Located in the massive star cluster NGC 3603, the supermassive star system, known under the name of A1, has a rotation period of 3.77 days. The masses were calculated by a combination of observations made with the SINFONI instrument, an integral field spectrograph operating on the Very Large Telescope on the site of the European Organisation for Astronomical Research in the Southern Hemisphere (ESO) in Chile, and infrared images coming from the Hubble Space Telescope.

The stars forming the A1 system are so massive and bright that the light they transmit shows characteristics that only "Wolf-Rayet" stars possess. Within the context of this work, a binary system transmitting X-rays at a power almost never seen in our Galaxy was also discovered near NGC 3603-A1.

Notes: NGC 3603 (entry number 3603 of the New General Catalogue) is a giant HII region in the Constellation Carina, in the Carina arm of our spiral Galaxy, the Milky Way, about 20,000 light years from the Sun. It was discovered by John Frederick William Herschel in 1834. NGC 3603 has an open cluster at its centre that contains approximately 2,000 bright and massive stars.

A Wolf-Rayet star is a hot, massive and evolved star exhibiting a very high loss of mass due to a strong stellar wind (similar to the solar wind).

Article: www3.interscience.wiley.com/journal/121358317/abstract?CRETRY=1&SRETRY=0

Source: University of Montreal

Explore further: Quest for extraterrestrial life not over, experts say

add to favorites email to friend print save as pdf

Related Stories

Candidate most massive binary star identified

Apr 17, 2013

Astronomers have observed a binary star that potentially weighed 300 to 400 solar masses at birth. The present day total mass of the two stars is between 200 and 300 times that of the Sun, depending on its ...

Stars: How big is big?

Dec 12, 2011

You may have seen one of these astronomical scale picture sequences, where you go from the Earth to Jupiter to the Sun, then the Sun to Sirius – and all the way up to the biggest star we know of VY Canis ...

Image: Starburst Cluster Shows Celestial Fireworks

Jul 06, 2010

(PhysOrg.com) -- Like a July 4 fireworks display, a young, glittering collection of stars looks like an aerial burst. The cluster is surrounded by clouds of interstellar gas and dust—the raw material for ...

Recommended for you

Quest for extraterrestrial life not over, experts say

6 hours ago

The discovery of an Earth-sized planet in the "habitable" zone of a distant star, though exciting, is still a long way from pointing to the existence of extraterrestrial life, experts said Friday. ...

Continents may be a key feature of Super-Earths

11 hours ago

Huge Earth-like planets that have both continents and oceans may be better at harboring extraterrestrial life than those that are water-only worlds. A new study gives hope for the possibility that many super-Earth ...

Exoplanets soon to gleam in the eye of NESSI

14 hours ago

(Phys.org) —The New Mexico Exoplanet Spectroscopic Survey Instrument (NESSI) will soon get its first "taste" of exoplanets, helping astronomers decipher their chemical composition. Exoplanets are planets ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

gopher65
not rated yet Sep 19, 2008
Does anyone else out there twitch everytime they remember that NGC stands for "New Galactic Catalogue"? "New" indeed.

More news stories

Impact glass stores biodata for millions of years

(Phys.org) —Bits of plant life encapsulated in molten glass by asteroid and comet impacts millions of years ago give geologists information about climate and life forms on the ancient Earth. Scientists ...

Researchers successfully clone adult human stem cells

(Phys.org) —An international team of researchers, led by Robert Lanza, of Advanced Cell Technology, has announced that they have performed the first successful cloning of adult human skin cells into stem ...