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宇宙尘埃对哈勃太空望远镜的影响
A T Kearsley1,2, R P Webb3, G W Grime3
1Science Innovation Platforms, Natural History Museum , London SW7 5BD, UK.
概括
哈勃太空望远镜的撞击结果显示,宇宙尘埃对更大的粒子的轨道碎片占主导地位. 返回硬件的分析表明微流星,而不是碎片,造成了最重要的超高速冲击.
科学领域:
- 太空科学 太空科学
- 行星科学 行星科学
- 材料科学 材料科学 材料科学
背景情况:
- 哈勃太空望远镜的太阳能阵列和摄像头散热器屏幕经历了超高速冲击.
- 返回的硬件为研究撞击残留物提供了独特的机会.
研究的目的:
- 分析返回的哈勃太空望远镜组件上的更大的冲击特征的组成和起源.
- 重新评估微型石与轨道碎片撞击的比例.
主要方法:
- 对撞击地点进行显微镜分析 (电子,离子,X射线光).
- 实验室实验以验证撞击器分析.
- 与现有的轨道碎片和微流星模型进行比较.
主要成果:
- 大多数 (~90%) >50微米的撞击是微流星 (酸盐,铁,螺旋).
- 构成表明小行星起源的微流星撞击.
- 大型轨道碎片的撞击数量比NASA ORDEM和ESA MASTER模型预测的要少.
结论:
- 微流星是地球低轨道航天器上较大的超高速撞击的主要来源.
- 当前的轨道碎片模型可能会高估碎片流量,低估微型石流量.
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