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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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Jupiter-Family Comets
Title
Jupiter-Family Comets
Title
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Description:
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These images of the Jupiter-family comets Johnson (top) and Shoemaker-Levy 3 (bottom) were both taken with Spitzer's multiband imaging photometer (MIPS) at a wavelength of 24 microns.
The fan-shaped region that stretches upward from Johnson's nucleus (yellow ball in the middle) represents the dust "tail" of the comet. Dust tails are created when small particles from a comet are swept backward by the Sun's radiation pressure.
The image of Shoemaker-Levy 3 (bottom) does not show a dust tail.
In both images the long thin trail of emission that precisely follows the orbit of the comet is believed to be a debris trail of solid material, ranging from millimeters to centimeters in size. Such particles, called meteoroids, are the same size as those that appear in meteor showers when they enter the Earth's atmosphere. Because any trace of water would evaporate in the Sun's heat, astronomers do not believe that debris trails contain ice.
These meteoroids have evaded detection in previous comet images because they are relatively faint in visible light. At mid-infrared wavelengths, meteoroids give off infrared radiation. Any object with an internal temperature higher than absolute zero (-273.5 degrees Celsius or zero Kelvin) produces thermal radiation; objects in the inner solar system give off radiation at mid-infrared wavelengths. Consequently, MIPS allows astronomers to study the production of meteoroids by comets whose orbits do not cross the Earth's path.
Spitzer images have also shown that there is more mass in the debris trails of comets than in their dust tails and gases.
The results of Spitzer's observations are consistent with those obtained by space probes that encountered comet Halley in 1986. In Halley's case, large particles produced by the comet were not only detected, but caused significant damage to the probes.
Description
These images of the Jupiter-family comets Johnson (top) and Shoemaker-Levy 3 (bottom) were both taken with Spitzer's multiband imaging photometer (MIPS) at a wavelength of 24 microns.
The fan-shaped region that stretches upward from Johnson's nucleus (yellow ball in the middle) represents the dust "tail" of the comet. Dust tails are created when small particles from a comet are swept backward by the Sun's radiation pressure.
The image of Shoemaker-Levy 3 (bottom) does not show a dust tail.
In both images the long thin trail of emission that precisely follows the orbit of the comet is believed to be a debris trail of solid material, ranging from millimeters to centimeters in size. Such particles, called meteoroids, are the same size as those that appear in meteor showers when they enter the Earth's atmosphere. Because any trace of water would evaporate in the Sun's heat, astronomers do not believe that debris trails contain ice.
These meteoroids have evaded detection in previous comet images because they are relatively faint in visible light. At mid-infrared wavelengths, meteoroids give off infrared radiation. Any object with an internal temperature higher than absolute zero (-273.5 degrees Celsius or zero Kelvin) produces thermal radiation; objects in the inner solar system give off radiation at mid-infrared wavelengths. Consequently, MIPS allows astronomers to study the production of meteoroids by comets whose orbits do not cross the Earth's path.
Spitzer images have also shown that there is more mass in the debris trails of comets than in their dust tails and gases.
The results of Spitzer's observations are consistent with those obtained by space probes that encountered comet Halley in 1986. In Halley's case, large particles produced by the comet were not only detected, but caused significant damage to the probes.
Description
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Release Date:
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2005/07/18
Release_Date
2005/07/18
Release Date
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Release Credit:
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NASA/JPL-Caltech/W. Reach (Caltech)
Release_Credit
NASA/JPL-Caltech/W. Reach (Caltech)
Release Credit
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Object name:
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Comet Johnson
Object_name
Comet Johnson
Object name
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Object name:
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Shoemaker-Levy 3
Object_name
Shoemaker-Levy 3
Object name
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Object type:
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Comets
Object_type
Comets
Object type
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Instrument:
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MIPS
Instrument
MIPS
Instrument
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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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Visible Light
facet_what
Visible Light
facet_what
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facet_what:
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TRACE
facet_what
TRACE
facet_what
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facet_what:
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Jupiter
facet_what
Jupiter
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_where:
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Jupiter
facet_where
Jupiter
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_when:
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1986
facet_when
1986
facet_when
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facet_when_year:
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1986
facet_when_year
1986
facet_when_year
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Image #:
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sig05-008
Image_#
sig05-008
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-sig05-008
UID
SPD-SPITZ-sig05-008
UID
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