* Astronomy

Members Login
Username 
 
Password 
    Remember Me  
Home -> Astronomy News -> Stars/galaxy News -> A1 binary system
Post Info TOPIC: A1 binary system
Blobrana


L

Posts: 131433
Date:
RE: A1 binary system
Permalink  
 

Des astrophysiciens de lUniversité de Montréal «pèsent» létoile la plus massive connue à ce jour
Les modèles théoriques de formation stellaire proposent lexistence détoiles très massives pouvant atteindre jusquà 150 fois la masse de notre Soleil. Pourtant, jusquà tout récemment, aucune étude navait été en mesure de découvrir une étoile de plus de 83 masses solaires.

Read more

__________________
Blobrana


L

Posts: 131433
Date:
Permalink  
 

Université de Montréal astrophysicists "weigh" galaxy's most massive star
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 scientists had discovered a star of more than 83 solar masses. Now an international team of astrophysicists, led by researchers from the Université de Montréal's Centre de recherche en astrophysique du Québec (CRAQ), have found and "weighed" the most massive star to date.

Read more

__________________
Blobrana


L

Posts: 131433
Date:
Permalink  
 

Astronomers have found a handful of stars in the 85-solar-mass range. But the data have everyone wondering: are there any 100-solar-mass stars?
A team at the University of Montreal now answers a tentative yes. Looking deep into NGC 3603, one of the youngest and most massive star clusters in the Milky Way, the scientists studied five extremely luminous stars. One is an only child, and the others are in two binary pairs. For one of the binaries, the team used shifts in the two stars spectral lines caused by the stars speeding around each other to calculate a rough mass for each companion. They came up with 85 to 145 solar masses for one, 75 to 105 solar masses for the other.

Read more

__________________
Blobrana


L

Posts: 131433
Date:
NGC3603-A1
Permalink  
 

Title: The very massive binary NGC3603-A1
Authors: O. Schnurr, A. F. J. Moffat, N. St-Louis, J. Casoli, A.-N. Chené

Using VLT/SINFONI, we have obtained repeated AO-assisted, NIR spectroscopy of the three central WN6ha stars in the core of the very young (~1 Myr), massive and dense Galactic cluster NGC3603. One of these stars, NGC3603-A1, is a known 3.77-day, double-eclipsing binary, while another one, NGC3603-C, is one of the brightest X-ray sources among all known Galactic WR stars, which usually is a strong indication for binarity. Our study reveals that star C is indeed an 8.9-day binary, although only the WN6ha component is visible in our spectra; therefore we temporarily classify star C as an SB1 system. A1, on the other hand, is found to consist of two emission-line stars of similar, but not necessarily of identical spectral type, which can be followed over most the orbit. Using radial velocities for both components and the previously known inclination angle of the system, we are able to derive absolute masses for both stars in A1. We find M_1 = (116 \pm 31) Mo for the primary and M_2 = (89 \pm 16) Mo for the secondary component of A1. While uncertainties are large, A1 is intrinsically half a magnitude brighter than WR20a, the current record holder with 83 and 82 Mo, respectively; therefore, it is likely that the primary in A1 is indeed the most massive star weighed so far.

Read more (114kb, PDF)

__________________
Blobrana


L

Posts: 131433
Date:
RE: A1 binary system
Permalink  
 

Thousands of sparkling young stars are nestled within the giant nebula NGC 3603, one of the most massive young star clusters in the Milky Way Galaxy. NGC 3603, a prominent star-forming region in the Carina spiral arm of the Milky Way about 20,000 light-years away, image reveals stages in the life cycle of stars. Powerful ultraviolet radiation and fast winds from the bluest and hottest stars have blown a big bubble around the cluster.
IMAGE (2247 x 2493)

Read more

-- Edited by Blobrana at 10:00, 2008-06-18

__________________
Blobrana


L

Posts: 131433
Date:
NGC 3603
Permalink  
 

Title: The Massive Star Content of NGC 3603
Authors: Nicholas W. Melena, Philip Massey, Nidia I. Morrell, Amanda M. Zangari

We investigate the massive star content of NGC 3603, the closest known giant H II region. We have obtained spectra of 26 stars in the central cluster using the Baade 6.5-m telescope (Magellan I). Of these 26 stars, 16 had no previous spectroscopy. We also obtained photometry of all of the stars with previous or new spectroscopy, primarily using archival HST ACS/HRC images. We use these data to derive an improved distance to the cluster, and to construct an H-R diagram for discussing the masses and ages of the massive star content of this cluster.

Read more (423kb, PDF)

__________________
Blobrana


L

Posts: 131433
Date:
RE: A1 binary system
Permalink  
 



__________________
Blobrana


L

Posts: 131433
Date:
NGC 3603
Permalink  
 

Thousands of sparkling young stars are nestled within the giant nebula NGC 3603. This stellar "jewel box" is one of the most massive young star clusters in the Milky Way Galaxy. NGC 3603 is a prominent star-forming region in the Carina spiral arm of the Milky Way, about 20,000 light-years away. This latest image from NASA's Hubble Space Telescope shows a young star cluster surrounded by a vast region of dust and gas. The image reveals stages in the life cycle of stars.

Source

Position (J2000): R.A. 11h 15m 9s.10 Dec. -61° 16' 17".00

__________________
Blobrana


L

Posts: 131433
Date:
Permalink  
 

One of the galaxy's most massive young star clusters is revealed in a stunning new image from the Hubble Space Telescope.
The cluster of thousands of stars lies 20,000 light years from Earth in the Carina spiral arm of our galaxy. It is embedded in a star-forming nebula called NGC 3603, a cloud of gas and dust with enough material to form 400,000 stars like the Sun. Watch a video zooming in on the star cluster's location in the sky by clicking on the image at right.
Most of the bright stars in the image are very hot and massive. Their radiation and stellar winds have blown out a large cavity in the nebula around them.
The three brightest ones at the heart of the cluster had previously appeared to be more massive than theory allows. But the Hubble investigation, led by Jesús Maíz Apellániz of the Instituto de Astrofísica de Andalucía in Granada, Spain, hints that each of these objects may actually be a blurring of light from two or more individual stars that are too close together to be observed as separate objects.
Previous measurements by Hubble and the Very Large Telescope (VLT) in Chile had come to the same conclusion for two of these star systems, indicating that the heaviest star involved is as massive as 114 Suns, which is at the borderline of what some theoretical models allow.

NGC3603
Expand (229kb, 1024 x 768)
Credit NASA/ESA/STScI/AURA

Read more

__________________
Blobrana


L

Posts: 131433
Date:
RE: A1 binary system
Permalink  
 

Two of the heftiest Stars found are found in the star cluster NGC 3603.
The double super heavyweights are actually in orbit around each other, and both break the record 83 times the suns mass for the most massive stars found to date.
The heavier of the two weighs in at a whopping 114 "solar masses," while its little brother is 84 solar masses. The discovery was presented June 7, 2007, at the meeting of the Canadian Astronomical Society at the Royal Military College of Canada in Kingston, Ontario. The two stars, which form a binary system called A1, are not only large, they are quite young. This makes sense since it is the largest and brightest of stars that live the briefest, according to stellar theory.
They are found at the position labelled "A1" in the overlay.

Position(2000): RA 11 15 7.12 Dec -61 15 34.15

A1 binary.kmz
Google Sky File

-- Edited by Blobrana at 18:41, 2008-01-11

__________________
1 2  >  Last»  | Page of 2  sorted by
Quick Reply

Please log in to post quick replies.
Home -> Astronomy News -> Stars/galaxy News -> A1 binary system


Create your own FREE Forum
Report Abuse 		Powered by ActiveBoard