FORMOSAT-7/COSMIC-2

FORMOSAT-7/COSMIC-2 is a six-satellite GNSS radio occultation constellation operated by NOAA in partnership with Taiwan's National Space Organization (NSPO), UCAR, the US Air Force, and JPL.^[1] The constellation launched on 25 June 2019 aboard a Falcon Heavy from Cape Canaveral and reached its mission design orbits in February 2021 after orbital adjustments from the initial 720 km deployment altitude.^[2][3]

All six satellites orbit at 520-550 km altitude and 24 degrees inclination, spaced across six orbital planes 60 degrees apart.^[4][1] The 24-degree-inclination orbits concentrate coverage over the tropical and subtropical atmosphere. Each satellite carries the TGRS Tri-GNSS Radio-occultation System (JPL/NASA), a multi-constellation receiver tracking GPS, GLONASS, and Galileo signals, along with an Ion Velocity Meter for ionospheric plasma drift measurements and a Radio Frequency Beacon for ionospheric tomography science.^[1][3]

The constellation delivers more than 4000 high-quality profiles per day.^[1] Multi-constellation reception substantially increases profile throughput compared to the single-constellation IGOR receiver on COSMIC-1, while the 24-degree orbit trades high-latitude coverage for enhanced sampling of the tropics relative to COSMIC-1's 72-degree inclination. Data are distributed in near real-time and post-processing modes through the UCAR CDAAC and Taiwan's TACC.^[1]