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Fomalhaut
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Title: An interferometric study of the Fomalhaut inner debris disk. I. Near-infrared detection of hot dust with VLTI/VINCI
Authors: Olivier Absil, Bertrand Mennesson, Jean-Baptiste Le Bouquin, Emmanuel Di Folco, Pierre Kervella, Jean-Charles Augereau

The innermost parts of dusty debris disks around main sequence stars are currently poorly known due to the high contrast and small angular separation with their parent stars. Using near-infrared interferometry, we aim to detect the signature of hot dust around the nearby A4 V star Fomalhaut, which has already been suggested to harbour a warm dust population in addition to a cold dust ring located at about 140 AU. Archival data obtained with the VINCI instrument at the VLTI are used to study the fringe visibility of the Fomalhaut system at projected baseline lengths ranging from 4 m to 140 m in the K band. A significant visibility deficit is observed at short baselines with respect to the expected visibility of the sole stellar photosphere. This is interpreted as the signature of resolved circumstellar emission, producing a relative flux of 0.88% 0.12% with respect to the stellar photosphere. While our interferometric data cannot directly constrain the morphology of the excess emission source, complementary data from the literature allow us to discard an off-axis point-like object as the source of circumstellar emission. We argue that the thermal emission from hot dusty grains located within 6 AU from Fomalhaut is the most plausible explanation for the detected excess. Our study also provides a revised limb-darkened diameter for Fomalhaut (2.223 0.022 mas), taking into account the effect of the resolved circumstellar emission.

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In 2006, astronomer Alice Quillen of the University of Rochester predicted that a planet of a particular size and orbit must lie within the dust of a nearby star. That planet has now been photographed by the Hubble Space Telescope, making it only the second planet ever imaged after an accurate prediction. The only other planet seen after an accurate prediction was Neptune, discovered more than 160 years ago.

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Fomalhaut b
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Hubble Directly Observes Planet Orbiting FomalhautAstronomers using NASA's Hubble Space Telescope have taken the first visible-light snapshot of a planet orbiting another star. The images show the planet, named Fomalhaut b, as a tiny point source of light orbiting the nearby, bright southern star Fomalhaut, located 25 light-years away in the constellation Piscis Australis. An immense debris disk about 21.5 billion miles across surrounds the star. Fomalhaut b is orbiting 1.8 billion miles inside the disk's sharp inner edge.

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First pictures taken of planet outside the solar system: Fomalhaut b
Astronomers have succeeded in taking the first visible light snapshot of a planet outside our home solar system.
The Hubble space telescope photographed the planet Fomalhaut b after researchers spent eight years attempting to pinpoint it.
The planets existence had been known since 2005 because its gravity had shaped the inner edge of a dust belt around its parent star, but it was only in May this year that researchers were able to pick it out in photographs taken by Hubble in 2004 and 2006.

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RE: Fomalhaut
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Fomalhaut 30 times as bright as sun
Between the last vestiges of the Summer Triangle Stars of Vega, Altair and Deneb and the oncoming panorama of the bright stars and constellations of winter, lies an autumn Colorado sky that is almost completely devoid of any truly bright stars.
Almost, that is, except for a single lonely sentinel to the south, the bluish-white star called Fomalhaut.

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Look southeast on any clear evening. In autumn, a solitary star brightens an otherwise empty area of sky. That's Fomalhaut, a star with an odd name but an interesting story.
Fomalhaut (FOAM'-a-lot) is the brightest star in the constellation Piscis Austrinus (PIE'-sis aw-STRY'-nuss), the Southern Fish. Piscis Austrinus is one of several "watery" autumn constellations. Above it are Capricornus the Sea Goat and Aquarius the Water Carrier. And to its left and upper left, respectively, are Cetus the Whale and Pisces the Fishes.

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Astronomers at the University of California, Berkeley, and NASA's Goddard Space Flight Center have released a rather remarkable Hubble image of a ring of dust around star Fomalhaut, described by New Scientist as resembling "the Great Eye of Sauron".

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A young star's strange elliptical ring of dust likely heralds the presence of an undiscovered Neptune-sized planet, says a University of Rochester astronomer in the latest Monthly Notices of the Royal Astronomical Society.
Stars in the early stages of life are surrounded by dust clouds that thin out and dissipate as the star reaches maturity, becoming rings in their final stages. One star, however, has a dust ring that has long puzzled astronomers because it is not centred around the star as usual. Instead, the ring is elliptical, with the parent star off to one side.

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Fomalhaut is a bright, young, star, a mere 25 light-year trip from planet Earth in the direction of the constellation Piscis Austrinus.


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Earlier infrared observations identified a torus of cold material surrounding the nearby star but the panels above detail the sharpest ever visible light-image of the stars dusty debris ring, recorded by the Hubble Space Telescope's ACS camera.
Overwhelming glare from the star is masked by an occulting disk in the cameras coronagraph.
The off-centre ring with a sharp inner boundary is taken to be strong evidence of a massive planet orbiting far from Fomalhaut, shaping and maintaining the ring's inner edge.
Starting 133 astronomical units (Earth-Sun distances) from Fomalhaut, the dusty ring itself is likely a larger, younger analogy of our own Kuiper Belt - the solar system's outer reservoir of icy bodies.




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