MERCURY RADAR IMAGING - EVIDENCE FOR POLAR ICE

被引：222

作者：

SLADE, MA ^{[1
]}

BUTLER, BJ ^{[1
]}

MUHLEMAN, DO ^{[1
]}

机构：

[1] CALTECH,DIV GEOL & PLANETARY SCI,PASADENA,CA 91125

来源：

SCIENCE | 1992年 / 258卷 / 5082期

关键词：

D O I：

10.1126/science.258.5082.635

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：

The first unambiguous full-disk radar mapping of Mercury at 3.5-centimeter wavelength, with the Goldstone 70-meter antenna transmitting and 26 antennas of the Very Large Array receiving, has provided evidence for the presence of polar ice. The radar experiments, conducted on 8 and 23 August 1991, were designed to image the half of Mercury not photographed by Mariner 10. The orbital geometry allowed viewing beyond the north pole of Mercury; a highly reflective region was clearly visible on the north pole during both experiments. This polar region has areas in which the circular polarization ratio (mu(c)) was 1.0 to 1.4; values < approximately 0.1 are typical for terrestrial planets. Such high values of mu(c) have hitherto been observed in radar observations only from icy regions of Mars and icy outer planet satellites.

引用

页码：635 / 640

页数：6

共 45 条

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[3]

CLARK PE, 1988, MERCURY, P77

[4]

CORNWELL TJ, 1983, ASTRON ASTROPHYS, V121, P281