Zuber Maria T, Phillips Roger J, Andrews-Hanna Jeffrey C, Asmar Sami W, Konopliv Alexander S, Lemoine Frank G, Plaut Jeffrey J, Smith David E, Smrekar Suzanne E
Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139-4307, USA.
Science. 2007 Sep 21;317(5845):1718-9. doi: 10.1126/science.1146995.
Both poles of Mars are hidden beneath caps of layered ice. We calculated the density of the south polar layered deposits by combining the gravity field obtained from initial results of radio tracking of the Mars Reconnaissance Orbiter with existing surface topography from the Mars Orbiter Laser Altimeter on the Mars Global Surveyor spacecraft and basal topography from the Mars Advanced Radar for Subsurface and Ionospheric Sounding on the Mars Express spacecraft. The results indicate a best-fit density of 1220 kilograms per cubic meter, which is consistent with water ice that has approximately 15% admixed dust. The results demonstrate that the deposits are probably composed of relatively clean water ice and also refine the martian surface-water inventory.
火星的两极都隐藏在分层冰层之下。我们通过将火星勘测轨道飞行器无线电跟踪初始结果所获得的重力场，与火星全球勘测者号航天器上的火星轨道激光高度计现有的表面地形数据以及火星快车号航天器上的火星地下和电离层探测先进雷达的底部地形数据相结合，计算出了南极分层沉积物的密度。结果表明，最佳拟合密度为每立方米1220千克，这与含有约15%混合尘埃的水冰一致。这些结果表明，这些沉积物可能由相对纯净的水冰组成，同时也完善了火星地表水储量的信息。
