Pluto colder than expected
Posted: Wed, Jan 4, 2006, 7:14 AM ET (1214 GMT)
The surface of the distant planet Pluto is about ten degrees colder than its moon, evidence of different compositions for the two objects. Millimeter-wave observations of the infrared emissions from Pluto and Charon, made by the Submillimeter Array observatory atop Mauna Kea, Hawaii, found that Pluto's surface has a temperature of 43 kelvins, about ten degrees colder than the surface of Charon, which closely matches the expected blackbody temperature at that distance from the Sun. Scientists said the difference is due to the different compositions of the two worlds: Pluto's surface features nitrogen ice, which sublimates to form a thin atmosphere that helps cool the surface, while Charon's surface is composed primarily of water ice, which requires much warmer temperatures to sublimate.
The surface of the distant planet Pluto is about ten degrees colder than its moon, evidence of different compositions for the two objects. Millimeter-wave observations of the infrared emissions from Pluto and Charon, made by the Submillimeter Array observatory atop Mauna Kea, Hawaii, found that Pluto's surface has a temperature of 43 kelvins, about ten degrees colder than the surface of Charon, which closely matches the expected blackbody temperature at that distance from the Sun. Scientists said the difference is due to the different compositions of the two worlds: Pluto's surface features nitrogen ice, which sublimates to form a thin atmosphere that helps cool the surface, while Charon's surface is composed primarily of water ice, which requires much warmer temperatures to sublimate.| <<previous article | next article>> |
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Space Force picks 14 companies for GEO surveillance program
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Saturday, April 25
Golden Dome dreams face harsh budget reality
POLITICO — 8:38 am ET (1238 GMT) Space Force’s Space Based Interceptor Program to Counter Growing Speed and Maneuverability of Modern Missile Threats in support of Golden Dome for America
US Space Force — 8:38 am ET (1238 GMT) Space Force Reveals $3.2B in Space-Based Interceptor Awards for Golden Dome
Air and Space Forces Magazine — 8:38 am ET (1238 GMT) Space Force names 12 companies to develop Golden Dome’s space-based interceptors
Defensescoop — 8:37 am ET (1237 GMT) Space Force doles out contracts for space-based interceptors as part of Golden Dome
Washington Examiner — 8:35 am ET (1235 GMT) |
