Calibration and validation (CAL/VAL) is a key technology for quantitative application of space-borne remote sensing data. However, the complex space environment can cause many uncertainties and degrade calibration accuracy. In-flight calibration is always needed. The thermal emission of the Moon is stable over hundreds of years because there is no atmosphere and no significant physical or chemical change on its surface. The deep space view of the Microwave Humidity Sounder onboard NOAA-18 has viewed the Moon many times every year. Under solar illumination, the lunar surface shows stable and periodical variation in microwave brightness temperature (TB). The Moon is a potential calibration source for thermal calibration

The related work was published in Science China Earth Sciences as "Calibration of the space-borne microwave humidity sounder based on real-time thermal emission from lunar surface." Based on the heat conductive equation, the temperature profiles of lunar regolith at different regions and local time are simulated numerically with the real-time solar radiance and angle of incidence.

The Perseverance rover has just landed on Mars. Meanwhile, its precursor Curiosity continues to explore the base of Mount Sharp (officially Aeolis Mons), a mountain several kilometers high at the center of the Gale crater. Using the telescope on the ChemCam instrument to make detailed observations of the steep terrain of Mount Sharp at a distance, a French-US team headed by William Rapin, CNRS researcher at the Institut de Recherche en Astrophysique et Planétologie (CNRS/Université Toulouse III/CNES), has discovered that the Martian climate recorded there alternated between dry and wetter periods, before drying up completely about 3 billion years ago.