Peanut-Star System - In a repeating cycle, one star moves to the front and blocks our view of the other. From Earth, the star system brightens and dims, as we see light from two stars, then only one star. The two stars in this system appear to be nearly identical, each 15 to 20 times the mass of our sun. Image Credit: Still frame excerpted from Ohio State University Research News animation videoPeanut-Stars New Discovery Of Double Star Systems
Through the measurement of the wavelength of light, and other confirming methods, astronomers using the Large Binocular Telescope (LBT) on Mt. Graham in Arizona, have discovered a unique star formation. In fact, with the information the astronomers developed, they were able to confirm a second such double star formation in a closer galaxy to our Oblate Spheroid.
What is unique about this discovery (and its seconding confirmation), is that it proved the existence of two massive stars that emit light in the yellow spectrum are closely orbiting each other in a stable system (for now). In fact, the stars are so close together that a large amount of stellar material is shared between them, so that the shape of the system resembles that of a peanut.
Through the measurement of the wavelength of light, and other confirming methods, astronomers using the Large Binocular Telescope (LBT) on Mt. Graham in Arizona, have discovered a unique star formation. In fact, with the information the astronomers developed, they were able to confirm a second such double star formation in a closer galaxy to our Oblate Spheroid.
What is unique about this discovery (and its seconding confirmation), is that it proved the existence of two massive stars that emit light in the yellow spectrum are closely orbiting each other in a stable system (for now). In fact, the stars are so close together that a large amount of stellar material is shared between them, so that the shape of the system resembles that of a peanut.
It is suspected that this may be a formation that signals an eventual supernovae event.
This excerpted from Ohio State University Research News -
TWO NEW STAR SYSTEMS ARE FIRST OF THEIR KIND EVER FOUND
By Pam Frost Gorder, Research News - Last updated 3/31/08
COLUMBUS, Ohio -- Astronomers have spied a faraway star system that is so unusual, it was one of a kind -- until its discovery helped them pinpoint a second one that was much closer to home.
In a paper published in a recent issue of the Astrophysical Journal Letters, Ohio State University astronomers and their colleagues suggest that these star systems are the progenitors of a rare type of supernova.
They discovered the first star system 13 million light years away, tucked inside Holmberg IX, a small galaxy that is orbiting the larger galaxy M81. They studied it between January and October 2007.
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The star system is unusual, because it’s what the astronomers have called a “yellow supergiant eclipsing binary”.
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In a repeating cycle, one star moves to the front and blocks our view of the other. From Earth, the star system brightens and dims, as we see light from two stars, then only one star.
Peanut-Star System - Side view of double star formation. Image Credit: Still frame excerpted from Ohio State University Research News animation video
The two stars in this system appear to be nearly identical, each 15 to 20 times the mass of our sun.
José Prieto, Ohio State University graduate student and lead author on the journal paper, analyzed the new star system as part of his doctoral dissertation.
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To his surprise, he uncovered another one a little less than 230,000 light years away in the Small Magellanic Cloud, a small galaxy that orbits our own Milky Way.
The star system had been discovered in the 1980s, but was misidentified.
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The stars were even the same size -- 15 to 20 times the mass of the sun -- and melded together in the same kind of peanut shape. The system was clearly a yellow supergiant eclipsing binary.
“We didn’t expect to find one of these things, much less two,” said Kris Stanek, associate professor of astronomy at Ohio State. “You never expect this sort of thing. But I think this shows how flexible you have to be in astrophysics.
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“It shows that there are still valuable discoveries hidden in plain sight. You just have to keep your eyes open and connect the dots.”
The find may help solve another mystery. Of all the supernovae that have been studied over the years, two have been linked to yellow supergiants -- and that’s two more than astronomers would expect.
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“When two stars orbit each other very closely, they share material, and the evolution of one affects the other,” Prieto said. “It’s possible two supergiants in such a system would evolve more slowly, and spend more time in the yellow phase -- long enough that one of them could explode as a yellow supergiant.”
The discovery of this yellow supergiant binary system is just the first result of a long-term LBT project to monitor stellar variability in the nearby universe.
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The LBT is an international collaboration among institutions in the United States, Italy and Germany. The LBT Corporation partners are: the University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; Ohio State University; The Research Corporation, on behalf of The University of Notre Dame, University of Minnesota, and University of Virginia.
Reference Here>>
This excerpted from Ohio State University Research News -
TWO NEW STAR SYSTEMS ARE FIRST OF THEIR KIND EVER FOUND
By Pam Frost Gorder, Research News - Last updated 3/31/08
COLUMBUS, Ohio -- Astronomers have spied a faraway star system that is so unusual, it was one of a kind -- until its discovery helped them pinpoint a second one that was much closer to home.
In a paper published in a recent issue of the Astrophysical Journal Letters, Ohio State University astronomers and their colleagues suggest that these star systems are the progenitors of a rare type of supernova.
They discovered the first star system 13 million light years away, tucked inside Holmberg IX, a small galaxy that is orbiting the larger galaxy M81. They studied it between January and October 2007.
----
The star system is unusual, because it’s what the astronomers have called a “yellow supergiant eclipsing binary”.
----
In a repeating cycle, one star moves to the front and blocks our view of the other. From Earth, the star system brightens and dims, as we see light from two stars, then only one star.
Peanut-Star System - Side view of double star formation. Image Credit: Still frame excerpted from Ohio State University Research News animation videoThe two stars in this system appear to be nearly identical, each 15 to 20 times the mass of our sun.
José Prieto, Ohio State University graduate student and lead author on the journal paper, analyzed the new star system as part of his doctoral dissertation.
----
To his surprise, he uncovered another one a little less than 230,000 light years away in the Small Magellanic Cloud, a small galaxy that orbits our own Milky Way.
The star system had been discovered in the 1980s, but was misidentified.
----
The stars were even the same size -- 15 to 20 times the mass of the sun -- and melded together in the same kind of peanut shape. The system was clearly a yellow supergiant eclipsing binary.
“We didn’t expect to find one of these things, much less two,” said Kris Stanek, associate professor of astronomy at Ohio State. “You never expect this sort of thing. But I think this shows how flexible you have to be in astrophysics.
----
“It shows that there are still valuable discoveries hidden in plain sight. You just have to keep your eyes open and connect the dots.”
The find may help solve another mystery. Of all the supernovae that have been studied over the years, two have been linked to yellow supergiants -- and that’s two more than astronomers would expect.
----
“When two stars orbit each other very closely, they share material, and the evolution of one affects the other,” Prieto said. “It’s possible two supergiants in such a system would evolve more slowly, and spend more time in the yellow phase -- long enough that one of them could explode as a yellow supergiant.”
The discovery of this yellow supergiant binary system is just the first result of a long-term LBT project to monitor stellar variability in the nearby universe.
----
The LBT is an international collaboration among institutions in the United States, Italy and Germany. The LBT Corporation partners are: the University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; Ohio State University; The Research Corporation, on behalf of The University of Notre Dame, University of Minnesota, and University of Virginia.
Reference Here>>
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