资源环境科技发展态势分析平台

We examined the first‐ever laser ranging interferometer (LRI) measurements of inter‐satellite tracking acquired by GRACE Follow‐On satellites. Through direct along‐orbit analysis of instantaneous inter‐satellite measurements, we demonstrate the higher sensitivity of LRI (than K‐band microwave ranging, KBR) to anomalies associated with the Earth static gravity field at high spatial resolutions of 100–200 km. We found that LRI captures gravitational signals as small as 0.1 nm/s² at 490 km altitude, improved by one order of magnitude from KBR. This allows LRI to uniquely detect un‐/mis‐modeled short wavelength gravitational perturbations. We employed all LRI data in 2019 to validate various state‐of‐the‐art global static gravity field models, and show that LRI measurements, even over one month, can distinguish subtle differences among the models computed from ~15 years of GRACE KBR and ~4 years of GOCE gradiometry data. Ultra‐precise LRI measurements will be yet another critical dataset for future gravity field model development.