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Collection:
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NASA Cassini-Huygens Collection
Collection
NASA Cassini-Huygens Collection
Collection
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Title:
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Iapetus Temperature Variation Map
Title
Iapetus Temperature Variation Map
Title
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Description:
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Iapetus Temperature Variation Map
description
Iapetus Temperature Variation Map
Description
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Full Description:
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This plot shows how daytime temperatures at low latitudes on the dark material on Saturn's moon Iapetus vary with time of day, from about 130 Kelvin (-226 Fahrenheit) at noon to about 70 Kelvin (-334 Fahrenheit) at sunset. The observations are compared to a "forecast" model (green line) which predicts temperatures based on an assumed value of a parameter called the "thermal inertia. This measures how well the surface can retain heat as conditions change. Rock or solid ice has a high thermal inertia, roughly 2,000,000 as measured in the obscure units used for thermal inertia, meaning that it is good at storing heat and cools down or heats up relatively slowly. On Iapetus, in contrast, temperatures drop precipitously in the afternoon as the Sun sinks towards the horizon, and a very small value of the thermal inertia (30,000 units) is needed in the model to match the data. This means that Iapetus's surface is extremely bad at storing heat, and is thus extremely fluffy, probably due to the pulverizing effect of billions of years of meteorite impacts, though the mysterious process that has darkened this side of Iapetus may also have played a role. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information about the Cassini-Huygens mission visit, http://saturn.jpl.n…and the instrument team's home page, http://cirs.gsfc.na… *Credit*: NASA/JPL/GSFC
Full_Description
This plot shows how daytime temperatures at low latitudes on the dark material on Saturn's moon Iapetus vary with time of day, from about 130 Kelvin (-226 Fahrenheit) at noon to about 70 Kelvin (-334 Fahrenheit) at sunset. The observations are compared to a "forecast" model (green line) which predicts temperatures based on an assumed value of a parameter called the "thermal inertia. This measures how well the surface can retain heat as conditions change. Rock or solid ice has a high thermal inertia, roughly 2,000,000 as measured in the obscure units used for thermal inertia, meaning that it is good at storing heat and cools down or heats up relatively slowly. On Iapetus, in contrast, temperatures drop precipitously in the afternoon as the Sun sinks towards the horizon, and a very small value of the thermal inertia (30,000 units) is needed in the model to match the data. This means that Iapetus's surface is extremely bad at storing heat, and is thus extremely fluffy, probably due to the pulverizing effect of billions of years of meteorite impacts, though the mysterious process that has darkened this side of Iapetus may also have played a role. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The composite infrared spectrometer team is based at NASA's Goddard Space Flight Center, Greenbelt, Md. For more information about the Cassini-Huygens mission visit, http://saturn.jpl.n…and the instrument team's home page, http://cirs.gsfc.na… *Credit*: NASA/JPL/GSFC Full Description
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Date:
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January 10, 2005
Date
January 10, 2005
Date
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Keywords:
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flyby
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Keywords:
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iapetus
keywords
iapetus
Keywords
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Keywords:
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saturn
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Keywords:
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moon
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Keywords:
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temperature
keywords
temperature
Keywords
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Keywords:
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map
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facet_what:
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Saturn
facet_what
Saturn
facet_what
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facet_what:
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Cassini
facet_what
Cassini
facet_what
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facet_what:
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Cassini-Huygens
facet_what
Cassini-Huygens
facet_what
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facet_what:
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Huygens Probe
facet_what
Huygens Probe
facet_what
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facet_what:
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Moon
facet_what
Moon
facet_what
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facet_what:
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Cassini Orbiter
facet_what
Cassini Orbiter
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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Iapetus
facet_what
Iapetus
facet_what
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facet_what:
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Spectrometer
facet_what
Spectrometer
facet_what
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facet_what:
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Infrared Spectrometer
facet_what
Infrared Spectrometer
facet_what
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facet_what:
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Composite Infrared Spectrometer
facet_what
Composite Infrared Spectrometer
facet_what
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facet_where:
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Saturn
facet_where
Saturn
facet_where
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facet_where:
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Jet Propulsion Laboratory
facet_where
Jet Propulsion Laboratory
facet_where
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facet_where:
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California
facet_where
California
facet_where
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facet_where:
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Washington
facet_where
Washington
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_where:
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Goddard Space Flight Center (GSFC)
facet_where
Goddard Space Flight Center (GSFC)
facet_where
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facet_when:
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January 10, 2005
facet_when
January 10, 2005
facet_when
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facet_when_year:
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2005
facet_when_year
2005
facet_when_year
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UID:
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SPD-SATRN-1283
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original url:
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original_url
original url
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