COSMIC-2 Mission Summary at Three Years in Orbit

Abstract

We summarize the status of the FORMOSAT-7/COSMIC-2 (COSMIC-2) mission which has completed its first three years in orbit. COSMIC-2 is a joint U.S./Taiwan program consisting of six satellites in low-inclination orbits with the following payloads: Global Navigation Satellite System radio occultation, in-situ ion velocity meter, and tri-band radio frequency beacon. The constellation is in its final orbit configuration and reached mission full operating capability in September 2021. An extensive calibration/validation campaign has to date enabled the release of all baseline neutral atmosphere products and nearly all baseline ionosphere products. The mission is providing usually more than 5000 neutral atmosphere RO profiles per day with a precision better than 2 μrad from 30–60 km altitude. Each day, nearly 12,000 combined total electron content occultations and arcs are generated with absolute accuracy of better than 3 TECU. IVM density precision is at or below the 1% requirement. Neutral atmosphere and ionosphere latency, measured from time of observation to product creation time, is below 30 min median. Data products are delivered in near real-time to operational weather and space weather centers and made available openly to the research community. New ionosphere products specifying the presence and absence of scintillation are under development and planned for future release.

3‐D Ionospheric Imaging Over the South American Region With a New TEC‐Based Ionospheric Data Assimilation System (TIDAS‐SA)

“…The COSMIC‐2 constellation, launched in June 2019, consists of six satellites positioned in evenly spaced circular orbits at an altitude of 550 km with a low‐inclination angle of 24° (Schreiner et al., 2020). The primary payload onboard each satellite is a Tri‐GNSS radio‐occultation system (TGRS) instrument, which is responsible for measuring various atmospheric‐ionospheric parameters, such as atmospheric bending, refractivity in the troposphere and stratosphere, as well as ionospheric TEC, electron density, and scintillation (Weiss et al., 2022). In particular, the ionospheric radio occultation products are currently yielding ∼4,000 daily electron density profiles with high vertical resolution of a few kilometers.…”

One‐Dimensional Variational Ionospheric Retrieval Using Radio Occultation Bending Angles: 2. Validation

“…However, during 2020, the time period of data used in this paper, all the satellites were not yet in their final orbit with some still being maneuvered from their launch altitude of 720 km. The final satellite (FS706) was lowered to its nominal altitude in February 2021 (Weiss et al., 2022). COSMIC‐2 follows the successful COSMIC‐1 program, which launched in April 2006 (Ho et al., 2020).…”

The Ionospheric Exploration Based on TJU#01 Meteorological Microsatellite Mission: Initial Results

“…The COSMIC‐2 receivers send down 50 Hz amplitude and phase profiles when the calculated on‐board S4 exceeds a programmable threshold. The scintillation data are verified to geolocate ionospheric irregularity regions using back‐propagation analysis, and via comparison to GOLD ultraviolet imagery (Carrano et al., 2021; Weiss et al., 2022). Using the similar approach first developed by Carrano et al.…”