The Silicate Material in Comets
The Silicate Material in Comets
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彗星中的硅酸盐物质
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
M. Hanner
中科院分区：
文献类型：
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作者：
M. Hanner
彗星中的硅酸盐似乎是高温结晶顽火辉石和镁橄榄石的混合物，加上在较低温度下形成的玻璃状或无定形颗粒。从10和20微米彗星光谱中鉴定的矿物与无水南极聚集体IDP的组成一致。彗星状硅酸盐的起源仍然令人费解。虽然来自IDP的证据指出晶体和玻璃质成分都是太阳前的起源，但晶体硅酸盐的特征只出现在年轻恒星天体的光谱中，直到演化后期，彗星才是尘埃的可能来源。
Silicates in comets appear to be a mix of high-temperature crystalline enstatite and forsterite plus glassy or amorphous grains that formed at lower temperatures. The mineral identifications from the 10 and 20 µm cometary spectra are consistent with the composition of anhydrous chondritic aggregate IDPs. The origin of the cometary silicates remains puzzling. While the evidence from the IDPs points to a pre-solar origin of both crystalline and glassy components, the signatures of crystalline silicates appear in the spectra of young stellar objects only at a late evolutionary stage, when comets are the likely source of the dust.