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Collection:
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NASA Spitzer Space Telescope Collection
Collection
NASA Spitzer Space Telescope Collection
Collection
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Title:
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Fomalhaut
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Description:
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The NASA Spitzer Space Telescope has obtained the first infrared images of the dust disc surrounding Fomalhaut, the 18th brightest star in the sky. Planets are believed to form from such a flattened disc-like cloud of gas and dust orbiting a star very early in its life. The Spitzer telescope was designed in part to study these circumstellar discs, where the dust particles are so cold that they radiate primarily at infrared wavelengths. Located in the constellation Piscis Austrinus, the parent star and its putative planetary system are found at a distance of 25 light-years.
Twenty years ago, the Infrared Astronomical Satellite, the first orbiting infrared telescope, detected much more infrared radiation coming from Fomalhaut than was expected for a normal star of this type. The dust is presumed to be debris left over from the formation of a planetary system. However, the satellite did not have adequate spatial resolution to image the dust directly. Subsequent measurements with sub-millimeter radio telescopes suggested that Fomalhaut is surrounded by a huge dust ring 370 astronomical units (an astronomical unit is the average distance between the Sun and Earth), or 34 billion miles (56 billion kilometers) in diameter. This corresponds to a size of nearly five times larger than our own solar system. Moreover, the sub-millimeter observations (far right image) revealed that the ring was inclined 20 degrees from an edge-on view.
The new images obtained with the multiband imaging photometer onboard Spitzer confirm this general picture, while revealing important new details of Fomalhaut's circumstellar dust. The 70-micron image (lower left) clearly shows an asymmetry in the dust distribution, with the southern lobe one-third brighter than the northern. Such an unbalanced structure could be produced by a collision between moderate-sized asteroids in the recent past (releasing a localized cloud of dust) or by the steering effects of ring particles by the gravitational influence of an unseen planet.
At 24 microns (upper left), the Spitzer image shows that the center of the ring is not empty. [Note that an image of a reference star was subtracted from the Fomalhaut image to reveal the faint disc emission.] Instead, the 'doughnut hole' is filled with warmer dust that extends inward to within at least 10 astronomical units of the parent star. This warm inner disc of dust occupies the region that is most likely to be occupied by planets and may be analogous to our solar system's 'zodiacal cloud' -- but with considerably more dust. One possible explanation for this warmer dust is that comets are being nudged out of the circumstellar ring by the gravitational influence of massive planets. These comets then loop in toward the central star, releasing dust particles just as comets do in our own solar system.
Description
The NASA Spitzer Space Telescope has obtained the first infrared images of the dust disc surrounding Fomalhaut, the 18th brightest star in the sky. Planets are believed to form from such a flattened disc-like cloud of gas and dust orbiting a star very early in its life. The Spitzer telescope was designed in part to study these circumstellar discs, where the dust particles are so cold that they radiate primarily at infrared wavelengths. Located in the constellation Piscis Austrinus, the parent star and its putative planetary system are found at a distance of 25 light-years.
Twenty years ago, the Infrared Astronomical Satellite, the first orbiting infrared telescope, detected much more infrared radiation coming from Fomalhaut than was expected for a normal star of this type. The dust is presumed to be debris left over from the formation of a planetary system. However, the satellite did not have adequate spatial resolution to image the dust directly. Subsequent measurements with sub-millimeter radio telescopes suggested that Fomalhaut is surrounded by a huge dust ring 370 astronomical units (an astronomical unit is the average distance between the Sun and Earth), or 34 billion miles (56 billion kilometers) in diameter. This corresponds to a size of nearly five times larger than our own solar system. Moreover, the sub-millimeter observations (far right image) revealed that the ring was inclined 20 degrees from an edge-on view.
The new images obtained with the multiband imaging photometer onboard Spitzer confirm this general picture, while revealing important new details of Fomalhaut's circumstellar dust. The 70-micron image (lower left) clearly shows an asymmetry in the dust distribution, with the southern lobe one-third brighter than the northern. Such an unbalanced structure could be produced by a collision between moderate-sized asteroids in the recent past (releasing a localized cloud of dust) or by the steering effects of ring particles by the gravitational influence of an unseen planet.
At 24 microns (upper left), the Spitzer image shows that the center of the ring is not empty. [Note that an image of a reference star was subtracted from the Fomalhaut image to reveal the faint disc emission.] Instead, the 'doughnut hole' is filled with warmer dust that extends inward to within at least 10 astronomical units of the parent star. This warm inner disc of dust occupies the region that is most likely to be occupied by planets and may be analogous to our solar system's 'zodiacal cloud' -- but with considerably more dust. One possible explanation for this warmer dust is that comets are being nudged out of the circumstellar ring by the gravitational influence of massive planets. These comets then loop in toward the central star, releasing dust particles just as comets do in our own solar system.
Description
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Release Date:
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2003/12/18
Release_Date
2003/12/18
Release Date
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Press Release:
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Press_Release
Press Release
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Release Credit:
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NASA/JPL-Caltech/K. Stapelfeldt (JPL), James Clerk Maxwell Telescope
Release_Credit
NASA/JPL-Caltech/K. Stapelfeldt (JPL), James Clerk Maxwell Telescope
Release Credit
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Image Credit:
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NASA/JPL-Caltech/K. Stapelfeldt (JPL), James Clerk Maxwell Telescope
Image_Credit
NASA/JPL-Caltech/K. Stapelfeldt (JPL), James Clerk Maxwell Telescope
Image Credit
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Object name:
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Fomalhaut (alpha PsA; HD 216956)
Object_name
Fomalhaut (alpha PsA; HD 216956)
Object name
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Object type:
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Circumstellar disk
Object_type
Circumstellar disk
Object type
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Position (J2000):
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*RA: *22h57m39.05s *Dec: *-29d37m20.05s
Position_(J2000)
*RA: *22h57m39.05s *Dec: *-29d37m20.05s
Position (J2000)
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Distance:
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25 light-years (7.7 parsecs)
Distance
25 light-years (7.7 parsecs)
Distance
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Constellation:
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Piscis Austrinus (the Southern Fish)
Constellation
Piscis Austrinus (the Southern Fish)
Constellation
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Wavelength:
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24 microns / 70 microns
Wavelength
24 microns / 70 microns
Wavelength
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Image scale:
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72x72 arcsec
Image_scale
72x72 arcsec
Image scale
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Observers:
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Karl Stapelfeldt, Principal Investigator (JPL/Caltech)
John Stansberry (University of Arizona)
Katherine Su (University of Arizona)
Charles Beichman (JPL/Caltech)
Dean Hines (Space Science Institute)
Elizabeth Holmes (NRC/JPL/Caltech)
Christine Chen (NRC/JPL/Caltech)
Massimo Marengo (Harvard University)
Jane Morrison (University of Arizona)
Michael Werner (JPL/Caltech)
George Rieke (University of Arizona)
Michael Jura (UCLA)
Thangasamy Velusamy (JPL)
Observers
Karl Stapelfeldt, Principal Investigator (JPL/Caltech)
John Stansberry (University of Arizona)
Katherine Su (University of Arizona)
Charles Beichman (JPL/Caltech)
Dean Hines (Space Science Institute)
Elizabeth Holmes (NRC/JPL/Caltech)
Christine Chen (NRC/JPL/Caltech)
Massimo Marengo (Harvard University)
Jane Morrison (University of Arizona)
Michael Werner (JPL/Caltech)
George Rieke (University of Arizona)
Michael Jura (UCLA)
Thangasamy Velusamy (JPL)
Observers
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Instrument:
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MIPS
Instrument
MIPS
Instrument
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Exposure Date:
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November 19, 2003
Exposure_Date
November 19, 2003
Exposure Date
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Exposure Time:
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193 seconds / 201 seconds per position
Exposure_Time
193 seconds / 201 seconds per position
Exposure Time
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Orientation:
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North is up
Orientation
North is up
Orientation
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Magnitude:
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1.23
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note:
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*24-micron image*
High-Resolution (384x384): JPEG | Mac TIFF | PC TIFF
Credit: NASA/JPL-Caltech/K. Stapelfeldt (JPL)
note
*24-micron image*
High-Resolution (384x384): JPEG | Mac TIFF | PC TIFF
Credit: NASA/JPL-Caltech/K. Stapelfeldt (JPL)
note
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note:
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*70-micron image*
High-Resolution (384x384): JPEG | Mac TIFF | PC TIFF
Credit: NASA/JPL-Caltech/K. Stapelfeldt (JPL)
note
*70-micron image*
High-Resolution (384x384): JPEG | Mac TIFF | PC TIFF
Credit: NASA/JPL-Caltech/K. Stapelfeldt (JPL)
note
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note:
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*24-70 micron composite*
High-Resolution (384x384): JPEG | Mac TIFF | PC TIFF
Credit: NASA/JPL-Caltech/K. Stapelfeldt (JPL)
note
*24-70 micron composite*
High-Resolution (384x384): JPEG | Mac TIFF | PC TIFF
Credit: NASA/JPL-Caltech/K. Stapelfeldt (JPL)
note
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note:
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*Radio comparison image*
High-Resolution (384x384): JPEG | Mac TIFF | PC TIFF
Credit: James Clerk Maxwell Telescope
note
*Radio comparison image*
High-Resolution (384x384): JPEG | Mac TIFF | PC TIFF
Credit: James Clerk Maxwell Telescope
note
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facet_what:
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Spitzer Space Telescope
facet_what
Spitzer Space Telescope
facet_what
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facet_what:
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Earth
facet_what
Earth
facet_what
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facet_what:
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Sun
facet_what
Sun
facet_what
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facet_what:
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COMETS
facet_what
COMETS
facet_what
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facet_what:
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MIPS
facet_what
MIPS
facet_what
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facet_what:
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FOMALHAUT
facet_what
FOMALHAUT
facet_what
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facet_what:
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Piscis Austrinus
facet_what
Piscis Austrinus
facet_what
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facet_where:
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Arizona
facet_where
Arizona
facet_where
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facet_where:
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Jet Propulsion Laboratory (JPL)
facet_where
Jet Propulsion Laboratory (JPL)
facet_where
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facet_where:
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Washington, D.C.
facet_where
Washington, D.C.
facet_where
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facet_when:
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November 19, 2003
facet_when
November 19, 2003
facet_when
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facet_when_year:
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2003
facet_when_year
2003
facet_when_year
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Image #:
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ssc2003-06i
Image_#
ssc2003-06i
Image #
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original url:
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original_url
original url
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UID:
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SPD-SPITZ-ssc2003-06 i
UID
SPD-SPITZ-ssc2003-06 i
UID
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