卡西尼号在恩塞拉多的尘埃测量和对E环起源的影响
Frank Spahn1, Jürgen Schmidt, Nicole Albers
1Institut für Physik, Universität Potsdam, Am Neuen Palais 10, Haus 19, D-14469 Potsdam, Germany.
Science (New York, N.Y.)
|March 11, 2006
概括
卡西尼号航天器的数据显示,土星的卫星环绕着土星的卫星恩塞拉多斯,有微米大小的尘埃颗粒. 这种尘埃很可能起源于恩塞拉多斯的地质活跃的南极地区,为土星的E环做出了贡献.
科学领域:
- 行星科学 行星科学
- 天文地质学 天文地质学
- 空间物理 空间物理
背景情况:
- 土星的E环是一个分散的环,主要由冰颗粒组成.
- 土星的一个卫星恩塞拉多斯 (Enceladus) 显示出地质活动的证据,包括羽毛和一个温暖的南极地区.
研究的目的:
- 为了调查卡西尼号任务期间在恒星周围检测到的尘埃颗粒的来源.
- 要确定恒星是否对土星的E环有重大贡献.
主要方法:
- 分析来自卡西尼号航天器上的宇宙尘埃分析仪 (CDA) 的数据.
- 尘埃撞击数据与航天器轨迹和其他卡西尼号实验发现的相关性.
主要成果:
- 高速探测器在恩塞拉多附近记录了微米大小的尘埃颗粒撞击的峰值,在最接近之前.
- 一个不对称的尘埃标志表明,埃塞拉多的南极地区有局部的尘埃产生.
- 同时的卡西尼号数据表明同一地区的地球物理活动 (高表面温度,水气释放).
结论:
- 环卫星是月球周围检测到的尘埃颗粒的可能来源.
- 恩塞拉多斯南极地区的地质物理过程是产生尘埃的原因.
- 恒星是土星E环的主要贡献者.
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