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IC-348-PIA12210.jpgCreation...104 visiteThis artist's conception shows a lump of material in a swirling, planet- forming disk. Astronomers using NASA's Spitzer Space Telescope found evidence that a companion to a star -- either another star or a planet -- could be pushing planetary material together, as illustrated here.
Planets are born out of spinning disks of gas and dust. They can carve out lanes or gaps in the disks as they grow bigger and bigger. Scientists used Spitzer's infrared vision to study the disk around a star called LRLL 31, located about 1000 LY away in the IC 348 Region of the constellation Perseus. Spitzer's new infrared observations reveal that the disk has both an inner and outer gap.
What's more, the data show that infrared light from the disk is changing over as little time as one week -- a very unusual occurrence. In particular, light of different wavelengths seesawed back and forth, with short-wavelength light going up when long-wavelength light went down, and vice versa.
According to astronomers, this change could be caused by a companion to the star (illustrated as a planet in this picture). As the companion spins around, its gravity would cause the wall of the inner disk to squeeze into a lump. This lump would also spin around the star, shadowing part of the outer disk. When the bright side of the lump is on the far side of the star, and facing Earth, more infrared light at shorter wavelengths should be observed (hotter material closer to the star emits shorter wavelengths of infrared light). In addition, the shadow of the lump should cause longer-wavelength infrared light from the outer disk to decrease. The opposite would be true when the lump is in front of the star and its bright side is hidden (shorter-wavelength light would go down, and longer- wavelength light up). This is precisely what Spitzer observed.
The size of the lump and the planet have been exaggerated to better illustrate the dynamics of the system.MareKromium02/16/16 at 10:52Anakin: Vediamo se ho capito qualcosa:
le onde gravitaz...
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IC-348-PIA12210.jpgCreation...104 visiteThis artist's conception shows a lump of material in a swirling, planet- forming disk. Astronomers using NASA's Spitzer Space Telescope found evidence that a companion to a star -- either another star or a planet -- could be pushing planetary material together, as illustrated here.
Planets are born out of spinning disks of gas and dust. They can carve out lanes or gaps in the disks as they grow bigger and bigger. Scientists used Spitzer's infrared vision to study the disk around a star called LRLL 31, located about 1000 LY away in the IC 348 Region of the constellation Perseus. Spitzer's new infrared observations reveal that the disk has both an inner and outer gap.
What's more, the data show that infrared light from the disk is changing over as little time as one week -- a very unusual occurrence. In particular, light of different wavelengths seesawed back and forth, with short-wavelength light going up when long-wavelength light went down, and vice versa.
According to astronomers, this change could be caused by a companion to the star (illustrated as a planet in this picture). As the companion spins around, its gravity would cause the wall of the inner disk to squeeze into a lump. This lump would also spin around the star, shadowing part of the outer disk. When the bright side of the lump is on the far side of the star, and facing Earth, more infrared light at shorter wavelengths should be observed (hotter material closer to the star emits shorter wavelengths of infrared light). In addition, the shadow of the lump should cause longer-wavelength infrared light from the outer disk to decrease. The opposite would be true when the lump is in front of the star and its bright side is hidden (shorter-wavelength light would go down, and longer- wavelength light up). This is precisely what Spitzer observed.
The size of the lump and the planet have been exaggerated to better illustrate the dynamics of the system.MareKromium02/12/16 at 17:29Ufologo: Ecco, anch'io desidererei saperne di pi? ... M...
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IC-348-PIA12210.jpgCreation...104 visiteThis artist's conception shows a lump of material in a swirling, planet- forming disk. Astronomers using NASA's Spitzer Space Telescope found evidence that a companion to a star -- either another star or a planet -- could be pushing planetary material together, as illustrated here.
Planets are born out of spinning disks of gas and dust. They can carve out lanes or gaps in the disks as they grow bigger and bigger. Scientists used Spitzer's infrared vision to study the disk around a star called LRLL 31, located about 1000 LY away in the IC 348 Region of the constellation Perseus. Spitzer's new infrared observations reveal that the disk has both an inner and outer gap.
What's more, the data show that infrared light from the disk is changing over as little time as one week -- a very unusual occurrence. In particular, light of different wavelengths seesawed back and forth, with short-wavelength light going up when long-wavelength light went down, and vice versa.
According to astronomers, this change could be caused by a companion to the star (illustrated as a planet in this picture). As the companion spins around, its gravity would cause the wall of the inner disk to squeeze into a lump. This lump would also spin around the star, shadowing part of the outer disk. When the bright side of the lump is on the far side of the star, and facing Earth, more infrared light at shorter wavelengths should be observed (hotter material closer to the star emits shorter wavelengths of infrared light). In addition, the shadow of the lump should cause longer-wavelength infrared light from the outer disk to decrease. The opposite would be true when the lump is in front of the star and its bright side is hidden (shorter-wavelength light would go down, and longer- wavelength light up). This is precisely what Spitzer observed.
The size of the lump and the planet have been exaggerated to better illustrate the dynamics of the system.MareKromium02/11/16 at 17:35Ivana Tognoloni: E allora Paolo, queste onde gravitazionali esiston...
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Kepler_10b-PIA13776.jpgExo-Planet "Kepler 10b"152 visiteCaption NASA:"Artist's concept of the first rocky world discovered by NASA's Kepler Mission. The Planet, called Kepler 10-b, is shown in front of its Host (Parent) Star".MareKromium04/19/14 at 20:35Ivana Tognoloni: Pensate a quelle creature che potrebbero vivere l?...
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Kepler_10b-PIA13776.jpgExo-Planet "Kepler 10b"152 visiteCaption NASA:"Artist's concept of the first rocky world discovered by NASA's Kepler Mission. The Planet, called Kepler 10-b, is shown in front of its Host (Parent) Star".MareKromium04/19/14 at 16:47KKK: Per Anakin: http: // www. lunexit.it/ trueplanets/...
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Kepler_10b-PIA13776.jpgExo-Planet "Kepler 10b"152 visiteCaption NASA:"Artist's concept of the first rocky world discovered by NASA's Kepler Mission. The Planet, called Kepler 10-b, is shown in front of its Host (Parent) Star".MareKromium04/19/14 at 08:20Anakin: Ma quanto influisce secondo voi la gravitazione di...
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Kepler_10b-PIA13776.jpgExo-Planet "Kepler 10b"152 visiteCaption NASA:"Artist's concept of the first rocky world discovered by NASA's Kepler Mission. The Planet, called Kepler 10-b, is shown in front of its Host (Parent) Star".MareKromium04/19/14 at 05:43Ufologo: .. sul "terminatore" ... *_*
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Kepler_10b-PIA13776.jpgExo-Planet "Kepler 10b"152 visiteCaption NASA:"Artist's concept of the first rocky world discovered by NASA's Kepler Mission. The Planet, called Kepler 10-b, is shown in front of its Host (Parent) Star".MareKromium04/18/14 at 17:48walthari: reputo possibile la formazione di forme di vita su...
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Kepler_10b-PIA13776.jpgExo-Planet "Kepler 10b"152 visiteCaption NASA:"Artist's concept of the first rocky world discovered by NASA's Kepler Mission. The Planet, called Kepler 10-b, is shown in front of its Host (Parent) Star".MareKromium04/18/14 at 17:12Ufologo: Penso prorio di s?, Paolo; un altro Tempo, un altr...
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Kepler_10b-PIA13776.jpgExo-Planet "Kepler 10b"152 visiteCaption NASA:"Artist's concept of the first rocky world discovered by NASA's Kepler Mission. The Planet, called Kepler 10-b, is shown in front of its Host (Parent) Star".MareKromium04/18/14 at 15:11KKK: Ho letto la notizia qualche giorno fa. Mi document...
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Kepler_10b-PIA13776.jpgExo-Planet "Kepler 10b"152 visiteCaption NASA:"Artist's concept of the first rocky world discovered by NASA's Kepler Mission. The Planet, called Kepler 10-b, is shown in front of its Host (Parent) Star".MareKromium04/18/14 at 14:52Anakin: E' stato individuato un pianeta simile alla te...
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GLS-SDSSJ0946+1006.jpgHubble Finds Double "Einstein Ring"53 visiteNASA's Hubble Space Telescope has revealed a never-before-seen optical alignment in space: a pair of glowing rings, one nestled inside the other like a bull's-eye pattern. The double-ring pattern is caused by the complex bending of light from two distant galaxies strung directly behind a foreground massive galaxy, like three beads on a string.
More than just a novelty, this very rare phenomenon can offer insight into dark matter, dark energy, the nature of distant galaxies, and even the curvature of the universe.
The ring was found by an international team of astronomers led by Raphael Gavazzi and Tommaso Treu of the University of California, Santa Barbara. The discovery is part of the ongoing Sloan Lens Advanced Camera for Surveys (SLACS) program. The team is reporting its results at the 211th meeting of the American Astronomical Society in Austin, Texas. A paper has been submitted to The Astrophysical Journal.
The phenomenon, called gravitational lensing, occurs when a massive galaxy in the foreground bends the light rays from a distant galaxy behind it, in much the same way as a magnifying glass would. When both galaxies are exactly lined up, the light forms a circle, called an "Einstein ring," around the foreground galaxy. If another background galaxy lies precisely on the same sightline, a second, larger ring will appear.
Because the odds of seeing such a special alignment are estimated to be 1 in 10,000, Tommaso says that they "hit the jackpot." The odds of seeing this phenomenon are less than winning two consecutive bets on a single number at Roulette.
"Such stunning cosmic coincidences reveal so much about nature. Dark matter is not hidden to lensing," added Leonidas Moustakas of the Jet Propulsion Laboratory in Pasadena, Calif. "The elegance of this lens is trumped only by the secrets of nature that it reveals."
The massive foreground galaxy is almost perfectly aligned in the sky with two background galaxies at different distances. The foreground galaxy is 3 billion light-years away. The inner ring and outer ring are comprised of multiple images of two galaxies at a distance of 6 billion and approximately 11 billion light-years.
SLACS team member Adam Bolton of the University of Hawaii's Institute for Astronomy in Honolulu first identified the lens in the Sloan Digital Sky Survey (SDSS). "The original signature that led us to this discovery was a mere 500 photons (particles of light) hidden among 500,000 other photons in the SDSS spectrum of the foreground galaxy," commented Bolton.
"The twin rings were clearly visible in the Hubble image, added Tommaso. "When I first saw it I said 'wow, this is insane!' I could not believe it!"
The distribution of dark matter in the foreground galaxies that is warping space to create the gravitational lens can be precisely mapped. Tommaso finds that the fall-off in density of the dark matter is similar to what is seen in spiral galaxies (as measured by the speed of a galaxy's rotation, which yields a value for the amount of dark matter pulling on it), though he emphasizes there is no physical reason to explain this relationship.
In addition, the geometry of the two Einstein rings allowed the team to measure the mass of the middle galaxy precisely to be a value of 1 billion solar masses. The team reports that this is the first measurement of the mass of a dwarf galaxy at cosmological distance (redshift of z=0.6).
A sample of several dozen double rings such as this one would offer a purely independent measure. The comparative radius of the rings could also be used to provide an independent measure of the curvature of space by gravity. This would help in determining the matter content of the universe and the properties of dark energy.
Observations of the cosmic microwave background (a relic from the Big Bang) favor flat geometry. A sample of 50 suitable double Einstein rings would be sufficient to measure the dark matter content of the universe and the equation of state of the dark energy (a measure of its pressure) to 10 percent precision. Other double Einstein rings could be found with wide-field space telescope sky surveys that are being proposed for the Joint Dark Energy Mission (JDEM) and recently recommended by the National Research Council.
MareKromium12/16/13 at 21:54paolocf1963: Come gi? scritto: chi mi trova "l'Errore&...
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