Distribution of rock, metals, and ices in Callisto

被引:67
作者
Anderson, JD
Schubert, G
Jacobson, RA
Lau, EL
Moore, WB
Sjogren, WL
机构
[1] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA
[2] Univ Calif Los Angeles, Inst Geophys & Planetary Phys, Dept Earth & Space Sci, Los Angeles, CA 90095 USA
关键词
D O I
10.1126/science.280.5369.1573
中图分类号
O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];
学科分类号
07 ; 0710 ; 09 ;
摘要
Radio Doppler data from a single encounter (C3) of the Galileo spacecraft with Callisto, the outermost Galilean moon of Jupiter, indicated that Callisto was probably undifferentiated. Now, similar data from a second encounter (C9) corroborate this conclusion, but more accurate data from a third encounter (C10) indicate that the rock and ice within Callisto have partially, but not completely, separated. Callisto may be differentiated into a rock-metal core less than 25 percent of Callisto's radius, an outer layer of clean ice less than 350 km thick, and a middle layer of mixed rock and ice. Models in which ice and rock are mixed all the way to the center of Callisto are also consistent with the data.
引用
收藏
页码:1573 / 1576
页数:4
相关论文
共 39 条
[1]   Gravitational constraints on the internal structure of Ganymede [J].
Anderson, JD ;
Lau, EL ;
Sjogren, WL ;
Schubert, G ;
Moore, WB .
NATURE, 1996, 384 (6609) :541-543
[2]   Gravitational evidence for an undifferentiated Callisto [J].
Anderson, JD ;
Lau, EL ;
Sjogren, WL ;
Schubert, G ;
Moore, WB .
NATURE, 1997, 387 (6630) :264-266
[3]  
ANDERSON JD, 1974, EXPT GRAVITATION, P163
[4]  
COHEN ER, 1996, PHYS TODAY, V49, pBG9
[5]   The role of extensional instability in creating Ganymede grooved terrain: Insights from Galileo high-resolution stereo imaging [J].
Collins, GC ;
Head, JW ;
Pappalardo, RT .
GEOPHYSICAL RESEARCH LETTERS, 1998, 25 (03) :233-236
[6]  
Davies ME, 1992, CELEST MECH DYN ASTR, V53, P377, DOI 10.1007/BF00051818
[7]   TIDAL DISSIPATION IN THE SOLID CORES OF THE MAJOR PLANETS [J].
DERMOTT, SF .
ICARUS, 1979, 37 (01) :310-321
[8]   VISCOSITY OF ROCK ICE MIXTURES AND APPLICATIONS TO THE EVOLUTION OF ICY SATELLITES [J].
FRIEDSON, AJ ;
STEVENSON, DJ .
ICARUS, 1983, 56 (01) :1-14
[9]  
HOBBS PV, 1974, ICE PHYSICS
[10]   POSSIBLE FLYBY MEASUREMENTS OF GALILEAN SATELLITE INTERIOR STRUCTURE [J].
HUBBARD, WB ;
ANDERSON, JD .
ICARUS, 1978, 33 (02) :336-341