Based on the previous applications of laser altimetry to planetary geodesy at GSFC, we use the recently developed PyXover software package to analyze altimetric crossovers from the Mercury Laser Altimeter (MLA). Using PyXover, we place new constraints on Mercury's geodetic parameters via least squares minimization of crossover discrepancies. We simultaneously solve for orbital corrections for each MLA ground track, for the geodetic parameters of the International Astronomical Union‐recommended orientation model for Mercury (pole right‐ascension and declination coordinates, prime meridian rotation rate, and librations), and for the Mercury's Love number h₂. We calibrate the formal errors of our solution based on closed‐loop simulations and on the level of robustness against a priori values, data selection, and parametrization. Our solution of the Mercury's rotational parameters is consistent with published values. In particular, our new estimate for the orientation of the pole places Mercury in a Cassini state, with an obliquity ϵ = 2.031 ± 0.03 arcmin compatible with previous “surface” related measurements. Moreover, we provide a first data‐based estimate of the Love number h₂ = 1.55 ± 0.65. The latter is consistent with expectations from models of Mercury's interior, although its precision does not enable their refinement.

中文翻译：

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从水银激光测高仪（MLA）得出具有高程交叉点的水银大地测量参数

基于GSFC的激光测高仪在行星大地测量学上的先前应用，我们使用最近开发的PyXover软件包来分析来自水星激光测高仪（MLA）的测高仪交叉。使用PyXover，通过最小化交叉差异的最小二乘，我们对水星的大地测量参数设置了新的约束。我们同时为每条MLA地面轨道，国际天文学联合会推荐的水星方向模型（极点右上角和偏角坐标，本初子午线旋转率和自由度）以及水星的爱的大地参数进行轨道校正。数h ₂。我们基于闭环仿真以及针对先验值，数据选择和参数化的鲁棒性级别，来校准解决方案的形式错误。我们对水星旋转参数的解决方案与已发布的值一致。特别是，我们对磁极定向的新估计使水星处于卡西尼状态，其倾角ϵ  = 2.031±0.03 arcmin，与以前的“表面”相关测量兼容。此外，我们提供了基于数据的洛夫数h ₂  = 1.55±0.65的第一个估计。后者与水星内饰模型的预期一致，尽管其精度无法对其进行完善。