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Updated: Feb 21, 2026

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Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
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小行星中没有异国情调的物质
Alan E Rubin1,2, Thomas H Burbine3
1Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, CA 90095-1567 USA.
概括
小行星密度通常在预期的物理极限内. 根据目前的证据,在像波利希姆尼亚这样的小行星中存在异常物质的说法,比如超重元素或暗物质,是极不可能的.
科学领域:
- 行星科学 行星科学
- 天体物理学 天体物理学
- 太空化学 太空化学
背景情况:
- 太阳系天体表现出不易挥发的元素的均丰度.
- 小行星被分类为未化的体或由化的体祖先形成的差异化物体.
- 基于反射光谱的小行星组成与石组成一致,石组成由酸盐和金属铁等常见材料组成.
研究的目的:
- 批判性地评估声称小行星 (33) Polyhymnia具有异常高的密度,暗示异国情调的组成.
- 为了评估含有超重元素 (SHEs),α物质或退化的暗物质的小行星的可能性.
- 根据已确定的物理和化学原理,加强对小行星组成的理解.
主要方法:
- 审查和分析已公布的小行星密度数据,包括异常值.
- 对小行星光谱数据与已知的石组成进行比较.
- 对理论模型的评估,建议在小行星中与观测证据和物理约束相对应的异国情调物质.
主要成果:
- 报告的小行星 (33) Polyhymnia (75.3 ± 9.7 g cm−3) 的散装密度被认为是不现实的和非物理的.
- 石,主要来自小行星,由非异国材料组成.
- 来自小行星的光谱数据,包括那些被标记为"紧超密物体" (CUDO) 的数据,与其分类学类内的其他小行星没有显著差异.
结论:
- 极其不太可能Polyhymnia或其他小行星含有外来物质,如稳定的超重元素或退化的暗物质.
- SHE和退化暗物质的存在仍然未被证明,而α物质通常只在极端的天体物理环境中发现.
- 小行星密度受到已知的物理和石组成的约束,支持非异国情调的物质基础.
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