Mars Soil Temperature and Thermal Properties from InSight HP3 Data

Diurnal and seasonal soil (and surface) temperature variations are reported, measured with the NASA InSight Mars mission’s HP3 thermal probe (and radiometer). At a representative depth of 10 – 20 cm, an average temperature of 217.5 K was found, varying by 5.3 – 6.7 K during a sol and by 13.3 K during the seasons. The damping of the surface temperature variation in the soil and the phase shift were used to derive a thermal diffusivity of 3.92 ± 0.39 × 10−8 m2/s for the top ∼10 cm from the diurnal variation and 3.63 ± 0.53 × 10−8 m2/s for the depth range of the mole of ∼40 cm from the annual temperature variation. The temperatures are conducive to the deliquescence of thin films of brine, which may explain the observed cemented duricrust. The thermal diffusivity suggests that published estimates of the depth to the cryosphere may need downward revision by around 5 %.本数据集记录了土壤（及地表）的昼夜与季节尺度温度变化，数据由NASA洞察号火星任务（NASA InSight Mars mission）搭载的HP3热探针（HP3 thermal probe）与辐射计（radiometer）测得。在典型的10~20厘米深度处，测得平均温度为217.5开尔文（K），该温度在单个火星日（sol）内波动幅度为5.3~6.7开尔文，季节尺度波动幅度达13.3开尔文。研究人员利用地表温度变化在土壤中的衰减效应与相移，分别基于昼夜温度变化与年际温度变化数据，推导出约10厘米浅层土壤的热扩散率（thermal diffusivity）为3.92±0.39×10^-8 平方米每秒（m²/s）；针对约40厘米深度的鼹鼠探测区间，则基于年际温度变化数据得到其热扩散率为3.63±0.53×10^-8 平方米每秒。该温度条件有利于卤水（brine）薄膜发生潮解（deliquescence），这或可解释观测到的胶结硬质结壳（duricrust）现象。上述热扩散率结果表明，已发表的火星冰冻圈（cryosphere）深度估算值或需下调约5%。

搜集汇总

背景与挑战

背景概述

该数据集基于NASA InSight火星任务的HP3热探针数据，报告了火星土壤温度的日变化和季节变化，测量深度在10-20厘米处平均温度为217.5 K，并推导了热扩散率。数据揭示了温度条件可能促进盐水薄膜潮解，从而解释胶结硬壳的形成，同时热扩散率表明现有冰冻圈深度估计可能需要向下修正约5%。