Corner cube retro-reflectors (CCRs), passive optical components, are used to independently evaluate the geolocation accuracy and effective laser footprint diameter of NASA's laser altimetry mission, ICESat-2, at two specific study sites: White Sands Missile Range in New Mexico and along a segment of the 88°S line of latitude in Antarctica. The CCR methodology provides ICESat-2 the ability to monitor these altimeter performance metrics throughout the mission lifetime as an indicator of the health of the instrument and the quality of the observations for science applications. The results using this technique reveal a mean geolocation accuracy of the ICESat-2 measurements of 3.5 m ± 2.1 m, meeting the mission requirement of 6.5 m. For those instances where multiple CCRs are illuminated, the mean effective laser footprint diameter is 10.9 m ± 1.2 m, with the variability assumed to be due to the influence of atmospheric conditions, but warrants further investigation.

中文翻译：

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用于监测在轨 ICESat-2 高度计地理定位和足迹直径的无源地基光学技术

角立方后向反射器 (CCR) 是无源光学组件，用于在两个特定研究地点独立评估 NASA 激光测高任务 ICESat-2 的地理定位精度和有效激光足迹直径：新墨西哥州的白沙导弹靶场和沿南极洲 88°S 纬度线的一段。CCR 方法使 ICESat-2 能够在整个任务生命周期内监测这些高度计性能指标，作为仪器健康状况和科学应用观测质量的指标。使用该技术的结果显示 ICESat-2 测量的平均地理定位精度为 3.5 m ± 2.1 m，满足 6.5 m 的任务要求。对于多个 CCR 被照亮的情况，平均有效激光足迹直径为 10.9 m ± 1。