相关实验视频
Updated: Jul 13, 2026

09:50
Measuring the Densities of Aqueous Glasses at Cryogenic Temperatures
Published on: June 28, 2017
阿马尔提亚的密度小于水的密度
John D Anderson1, Torrence V Johnson, Gerald Schubert
1Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA. john.d.anderson@jpl.nasa.gov
概括
利略航天器的数据显示,木星的卫星阿马尔提亚的密度很低,这表明它是多孔的,由冰和岩石组成. 这表明阿马尔提亚可能是在太阳系中较冷的区域形成的.
科学领域:
- 行星科学 行星科学
- 天体物理学 天体物理学
- 太阳系探索 太阳系探索
背景情况:
- 阿马尔提亚是木星内部的小卫星之一.
- 了解小卫星的组成和起源,可以了解太阳系的形成.
研究的目的:
- 为了确定Amalthea的质量,体积和密度.
- 推断阿马尔提亚的组成和形成位置.
主要方法:
- 来自利略航天器与阿马尔提亚相遇的无线电多普勒数据.
- 来自旅行者和利略航天器的图像分析.
主要成果:
- 确定阿马尔提亚的质量为 (2.08 +/- 0.15) x 10 ^ 18 公斤.
- 计算的体积是 (2.43 +/- 0.22) x 10^6 公里^3.
- 发现阿马尔提亚的密度为857 +/- 99 kg/m^3.3.
结论:
- 阿马尔提亚的低密度表明它是多孔的,由水冰和岩石材料组成.
- 构成表明阿马尔提亚可能是在太阳系的寒冷区域形成的,可能不是它的当前位置.
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