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Io
Io The third-largest satellite of Jupiter, diameter 3643 km, and the innermost of the four Galilean satellites; also known as Jupiter I. It orbits in 1.769 days at a distance of 422 000 km, keeping the same face turned towards Jupiter. Its geometric albedo is 0.6 and its opposition magnitude 5.0. The two Voyager spacecraft in 1979 revealed that Io has explosively erupting volcanoes which eject plumes of material over 300 km high, some of it landing up to 500 km from the eruption site. The sources of the eruptions are volcanic calderas or fissures, of which there are over 300. Huge lava flows radiate from many of the volcanoes, and the whole surface is yellowish in colour due to deposits of sulphur or sulphur oxides. There are extensive plains and mountainous regions on Io but no impact craters, indicating that its surface is geologically very young. Io's density, 3.53g/cm3, suggests that it has an iron–sulphur core about 1500 km across and a silicate mantle. Io's volcanic activity is the result of heat released by tidal forces, which deform the satellite as it moves closer and further away from Jupiter in its orbit.
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"Io." A Dictionary of Astronomy. 1997. Encyclopedia.com. 24 May. 2012 <http://www.encyclopedia.com>. "Io." A Dictionary of Astronomy. 1997. Encyclopedia.com. (May 24, 2012). http://www.encyclopedia.com/doc/1O80-Io.html "Io." A Dictionary of Astronomy. 1997. Retrieved May 24, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-Io.html |
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Io
Io (Jupiter I) One of the Galilean satellites and the most geologically (and especially volcanically) active body in the solar system, its volcanoes being due to heat generated by tidal heating and eruption temperatures reaching more than 1000 K. Io radiates more heat than it receives from the Sun. The Voyager spacecraft observed 9 volcanic eruptions. It has a metallic core, rock mantle, and a rocky surface covered with sulphur and sulphur compounds, including sulphur dioxide frost. Io was discovered in 1610 by Simon Marius and Galileo. Its equatorial radius is 1821.3 km; mass 8.93 × 1022 kg; mean density 3530 kg/m3; visual albedo 0.61; mean distance from Jupiter 421 600 km; orbital period 1.769138 days; rotational period 1.769138 days; surface temperature about −143°C, but with one volcanic feature with a temperature measured as 17°C.
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AILSA ALLABY and MICHAEL ALLABY. "Io." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 24 May. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "Io." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (May 24, 2012). http://www.encyclopedia.com/doc/1O13-Io.html AILSA ALLABY and MICHAEL ALLABY. "Io." A Dictionary of Earth Sciences. 1999. Retrieved May 24, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-Io.html |
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Io
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"Io." World Encyclopedia. 2005. Encyclopedia.com. 24 May. 2012 <http://www.encyclopedia.com>. "Io." World Encyclopedia. 2005. Encyclopedia.com. (May 24, 2012). http://www.encyclopedia.com/doc/1O142-Io.html "Io." World Encyclopedia. 2005. Retrieved May 24, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-Io.html |
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Io
Io , in astronomy, one of the 39 known moons, or natural satellites, of Jupiter . Io is subject to Jupiter's enormous tidal forces and is, as a result, the most volcanically active body in the solar system. |
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"Io." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 24 May. 2012 <http://www.encyclopedia.com>. "Io." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 24, 2012). http://www.encyclopedia.com/doc/1E1-Io-ast.html "Io." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 24, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-Io-ast.html |
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IO
IO An abbreviation for Input/Output, the processes and devices used to communicate with a computer system.
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DARREL INCE. "IO." A Dictionary of the Internet. 2001. Encyclopedia.com. 24 May. 2012 <http://www.encyclopedia.com>. DARREL INCE. "IO." A Dictionary of the Internet. 2001. Encyclopedia.com. (May 24, 2012). http://www.encyclopedia.com/doc/1O12-IO.html DARREL INCE. "IO." A Dictionary of the Internet. 2001. Retrieved May 24, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O12-IO.html |
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Io
Io •bio, Cetshwayo, Io, ngaio, Ohio
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"Io." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 24 May. 2012 <http://www.encyclopedia.com>. "Io." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (May 24, 2012). http://www.encyclopedia.com/doc/1O233-Io.html "Io." Oxford Dictionary of Rhymes. 2007. Retrieved May 24, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-Io.html |
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IO
IO India Office
• inspecting officer • integrated optics • intelligence officer • Irish vehicle registration for Kildare |
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FRAN ALEXANDER , PETER BLAIR , JOHN DAINTITH , ALICE GRANDISON , VALERIE ILLINGWORTH , ELIZABETH MARTIN , ANNE STIBBS , JUDY PEARSALL , and SARA TULLOCH. "IO." The Oxford Dictionary of Abbreviations. 1998. Encyclopedia.com. 24 May. 2012 <http://www.encyclopedia.com>. FRAN ALEXANDER , PETER BLAIR , JOHN DAINTITH , ALICE GRANDISON , VALERIE ILLINGWORTH , ELIZABETH MARTIN , ANNE STIBBS , JUDY PEARSALL , and SARA TULLOCH. "IO." The Oxford Dictionary of Abbreviations. 1998. Encyclopedia.com. (May 24, 2012). http://www.encyclopedia.com/doc/1O25-IO.html FRAN ALEXANDER , PETER BLAIR , JOHN DAINTITH , ALICE GRANDISON , VALERIE ILLINGWORTH , ELIZABETH MARTIN , ANNE STIBBS , JUDY PEARSALL , and SARA TULLOCH. "IO." The Oxford Dictionary of Abbreviations. 1998. Retrieved May 24, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O25-IO.html |
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