Submillimeter lightcurves of vesta

被引：12

作者：

Chamberlain, Matthew A. ^{[1
]}

Lovell, Amy J. ^{[2
]}

Sykes, Mark V. ^{[1
]}

机构：

[1] Planetary Sci Inst, Tucson, AZ 85719 USA

[2] Agnes Scott Coll, Decatur, GA 30030 USA

来源：

ICARUS | 2007年 / 192卷 / 02期

基金：

美国国家航空航天局;

关键词：

asteroid vesta; asteroids; surfaces; photometry; radio observations; infrared observations;

D O I：

10.1016/j.icarus.2007.08.003

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

Thermal lightcurves of Asteroid Vesta with significant amplitude have been observed at 870 pm (345 GHz) using the MPIfR 19-channel bolometer of the Heinrich-Hertz Submillimeter Telescope. Shape and albedo are not sufficient to explain the magnitude of this variation, which we relate to global variations in thermal inertia and/or other thermophysical parameters. Vesta's lightcurve has been observed over several epochs with the same general shape. However, there are some changes in morphology that may in part be related to viewing geometry and/or asteroid season. Inconsistent night-to-night variations exhibit the inherent difficulties in photometry at this wavelength. We are able to match the observed brightness temperatures with a relatively simple thermal model that integrates beneath the surface and assumes reasonable values of thermal inertia, loss tangent and refractive index, and without having to assume low values of emissivity in the submillimeter. High flux portions of the submillimeter lightcurve are found to correspond to regions with weak mafic bands observed in Hubble Space Telescope images. (c) 2007 Elsevier Inc. All rights reserved.

引用

页码：448 / 459

页数：12

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[2]

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