Infrared observations of Comet Austin (1990 V) by the COBE/Diffuse Infrared Background Experiment
Infrared observations of Comet Austin (1990 V) by the COBE/Diffuse Infrared Background Experiment
复制标题
COBE/漫红外背景实验对奥斯汀彗星 (1990 V) 的红外观测
DOI：
10.1086/187514
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
R. Silverberg
中科院分区：
文献类型：
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作者：
C. Lisse;H. Freudenreich;M. Hauser;T. Kelsall;S. Moseley;W. Reach;R. Silverberg
1990年5月，在奥斯汀彗星近地经过期间，由宇宙背景探测器(COBE)/漫反射红外背景实验(DIRBE)利用1-240微米的宽带测光技术观测到了这颗彗星。在12微米和25微米处发现了一条6度长(6x10(Exp 6)公里)的尘埃尾巴，由于粒子性质和质量损失率的不同，其结构细节也有所不同。中心42×42平方反正象素的光谱与温度为309+/-5K、光学厚度为7.3+/-10(Exp-8)的灰体光谱一致。与IUE和地面观测的比较表明，半径大于20微米的粒子以表面积为主。对于由粒子质量分布dN/dlogm近似近似的Mie球组成的模型尘埃尾巴，质量损失率为510(+510/-205)kg/S，总尾部质量为7+/-2×10(Exp 10)kg。M(Exp-0.63)和2：1硅酸盐：无定形碳质量组成。
Comet Austin was observed by the Cosmic Background Explorer (COBE)/Diffuse Infrared Background Experiment (DIRBE) with broadband photometry at 1-240 micrometers during the comet's close passage by Earth in 1990 May. A 6 deg long (6 x 10(exp 6) km) dust tail was found at 12 and 25 micrometers, with detailed structure due to variations in particle properties and mass-loss rate. The spectrum of the central 42 x 42 sq arcmin pixel was found to agree with that of a graybody of temperature 309 +/- 5 K and optical depth 7.3 +/- 10(exp -8). Comparison with IUE and ground-based obervations indicates that particles of radius greater than 20 micrometers predominate by surface area. A mass-loss rate of 510 (+510/-205) kg/s and a total tail mass of 7 +/- 2 x 10(exp 10) kg was found for a model dust tail composed of Mie spheres with a differential particle mass distribution dn/d log m approx. m(exp -0.63) and 2:1 silicate:amorphous carbon composition by mass.