Peanut-Stars | New Discovery Of Double Star Systems

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 video

Peanut-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.

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.
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The Oblate Spheroid, An Earthworm's View - Fossil Forest Find

Trees Stuck In Time - Image Credit: St. Louis Post-Dispatch

The Oblate Spheroid, An Earthworm's View - Fossil Forest Find

Last week, geologists surveying a coalmine 250 feet below the current surface of the Earth's crust, came upon a preserved 300 million year old forest. Measuring over four-square miles in size, the discovery is the largest fossil forest ever to date (as mining continues, the size of the exposed fossil forest grows by the day).

The discovery of the fossil remains were in the ceiling of the coalmine and are unusual, in that the fossilized trees of a forest are still standing and preserved standing straight up, as if frozen in time.

This left lead study author Bill DiMichele, a pale botanist at the Smithsonian Institution, to observe, "We get to walk under it and look up at it," he said. "It's the earthworm's view."

Sunken Forest and Peat Cuttings - Submerged for thousands of years, and now very much visible, the Historic Sunken Forest and the Peat Cuttings on Tywyn Beach [Wales]. Not a lot is known why it is there but due to beach erosion more is showing than ever before. Image Credit: ria3 via Flickr Fossils

Excerpts from the St. Louis Post-Dispatch -

Geologists discover world's largest fossil forest in the ceiling of an Illinois coal mine
By Eric Hand - ST. LOUIS POST-DISPATCH - 04/24/2007

Illinois geologists have discovered the remains of one of the world's oldest tropical rainforests, preserved in the ceiling of a coal mine 250 feet below the surface.

The four-square-mile fossil forest — the largest find ever — is just south of Danville in Vermilion County, Ill., in the 300-million-year-old Herrin coal bed, a 6-foot-thick strip mined by a subsidiary of St. Louis-based Peabody Coal.

Plant fossils are common in coal beds. Coal, after all, is the compacted result of peaty plant material. But scientists are surprised by the size of this fossil bed, which they suspect came about because of a freak, fortuitous event: an earthquake that flooded and buried the forest. The vast extent of the fossil forest, which existed in a swampy time of giant dragonflies and tree ferns, has allowed the scientists to infer subtle ecological changes across the ancient landscape.

"This is almost as good as insects in amber," said Scott Elrick of the Illinois State Geological Survey and one of the authors of the study, which was published in the May issue of the journal Geology.
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These are the remnants of extinct plants from a geological period 300 million years ago, called the Carboniferous, when the world was covered in a riot of green. Illinois was near the equator and much warmer and wetter.

It was also a time before flowering plants had evolved, and so the plants would seem bizarre to modern eyes, said study co-author Howard Falcon-Lang, a geologist at the University of Bristol in the United Kingdom.

"These are some of the earliest known rainforests to evolve on our planet," he said. "It was like something out of Jules Verne."

Giant tree ferns would have formed a lower canopy 30 feet high. Poking up through the ferns would have been 100-foot-tall clubmosses — asparagus-like poles that sprouted crowns full of spores. It was the age of insects, with 6-foot-long millipedes and dragonflies with yard-long wingspans.

The photo "Fosilillos" was taken next to the Bay of Biscay on the North coast near Bilbao, Spain – Image Credit: Mr. Theklan via Flickr Fossils
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An earthquake preserved all this for posterity. Elrick says it was akin to the 1811-12 earthquakes near New Madrid, Mo., which dropped a block of earth containing the Mississippi River, creating a natural dam that made Reelfoot Lake in Tennessee.

When the ancient earthquake hit, a sudden flooding in the submerged block killed the rainforest. Mud and silt rushed into the depression, preserving the stumps and logs in a layer that eventually became shale.

And that was the state of things until, 300 million years later, miners noticed shiny, funnel-shaped concretions that occasionally fell from the shale layer above them. They called them "kettlebottoms." But they were really fossilized stumps, whose roots fingered the peaty layer that ultimately became the coal seam the miners were working in.
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Lead study author Bill DiMichele, a paleobotanist at the Smithsonian Institution, said the lateral extent of the fossils allowed him to notice subtle changes in species diversity as he did surveys.
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DiMichele is now doing inventories of ancient plants in two other actively mined Illinois coal seams, the Danville and the Springfield, which sit above and below the Herrin, respectively, and are separated by about a half-million years of geological time. Where most botanists do their work by walking through a forest, DiMichele takes elevators down mine shafts — to get beneath the forest.
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