Large longitude libration of Mercury reveals a molten core

被引：244

作者：

Margot, J. L.

Peale, S. J.

Jurgens, R. F.

Slade, M. A.

Holin, I. V.

机构：

[1] Cornell Univ, Dept Astron, Ithaca, NY 14853 USA

[2] Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA

[3] CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA

[4] Space Res Inst, Moscow, Russia

来源：

SCIENCE | 2007年 / 316卷 / 5825期

关键词：

D O I：

10.1126/science.1140514

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：

Observations of radar speckle patterns tied to the rotation of Mercury establish that the planet occupies a Cassini state with obliquity of 2.11 +/- 0.1 arc minutes. The measurements show that the planet exhibits librations in longitude that are forced at the 88-day orbital period, as predicted by theory. The large amplitude of the oscillations, 35.8 +/- 2 arc seconds, together with the Mariner 10 determination of the gravitational harmonic coefficient C-22, indicates that the mantle of Mercury is decoupled from a core that is at least partially molten.

引用

页码：710 / 714

页数：5

共 45 条

[1] Crustal remanence in an internally magnetized non-uniform shell: a possible source for Mercury's magnetic field? [J].