The CORBES mission is designed to use a multi-satellite configuration to explore variations in the radiation belts by maintaining a near-equatorial orbit, with an apogee at approximately seven Earth radii, akin to Geostationary Transfer Orbits (GTO). By placing multiple satellites in this orbit, CORBES will discern spatial from temporal radiation belt changes, significantly enhancing our understanding of these dynamic regions. Each satellite is expected to operate for a minimum of one year, ensuring cost-effectiveness and mission continuity.

Aiming to deepen our grasp of outer radiation belt dynamics, the mission will leverage its CubeSat constellation to gather highly detailed measurements of energetic electron flux, geomagnetic field shifts, and plasma waves. This data will provide insights into physical processes that impact the radiation belt, including:

- Energy diffusion: Triggered by local resonant electron interactions with Very Low Frequency (VLF) waves like whistler-mode waves, especially during geomagnetic storms.

- Pitch angle scattering: Resulting from interactions between electrons and magnetospheric plasma waves, including whistler hiss and electromagnetic ion cyclotron (EMIC) waves.

- Radial transport: Caused by drift resonance between electrons and Ultra-Low-Frequency (ULF) waves, as well as sudden electric field changes from large-scale magnetic field alterations such as shock-induced injection and storm convection.

- Electron escape: Occurs as electrons exit the magnetosphere into the solar wind via magnetopause shadowing and other outward radial transport mechanisms.

This in-depth analysis will allow CORBES to build a more complete understanding of electron transport, acceleration, and loss mechanisms, refining both scientific models and predictive tools for the radiation belt environment.

Each CORBES satellite will carry a suite of three primary instruments: the Magnetometer (MAG), Search Coil Wave Detector (SCWD), and High Energy Electron Detector (HEED). These instruments are intended to operate in highly inclined, elliptical orbits reaching perigee at 280 km and apogee at 7 Earth radii, with an orbit period of about 13.5 hours. During each 10.5-hour pass through the outer radiation belt, these CubeSats will gather precise data on magnetic fields and electron populations. Spin-stabilized at approximately eight rotations per minute, each satellite's sun-facing axis provides orientation consistency. With a mass limit of 30 kg per satellite, the mission is designed for efficiency and cost-effectiveness.

Communication and data transmission will utilize S-band for command functions and X-band for downlink, with the satellites planned for deployment via one or two rockets. This coordinated deployment allows individual releases for each satellite, ensuring their placement within the intended orbit.

The mission's Assembly Integration and Testing (AIT), radiation shielding, and cross-calibration are essential. In particular, in-orbit cross-calibration ensures data consistency, using observations from specific conditions to align readings across multiple instruments. HEED's cross-calibration, for example, compares electron selection data during quiet magnetospheric phases, while MAG and SCWD use calm period data to verify their measurements.

The CORBES mission involves contributions from multiple international partners. Harbin Institute of Technology (HIT), Innovation Academy of Microsatellites (IMAC), and Finland's Foresail program have each contributed satellite technology, with IMAC contributing two satellites. Instrumentation is shared among institutions including the National Space Science Center (NSSC), Beihang University, and the University of Turku, ensuring a robust equipment lineup that supports the mission's goals.

CORBES operates under a data-sharing policy that will grant open access to its collected data, thereby aiding contributors and the global research community in understanding magnetospheric dynamics. COSPAR has supported mission organization, coordination, and partnerships with academic and government institutions.

The mission has already held over forty collaborative meetings, gathering input from scientists worldwide to define CORBES's objectives and payload requirements. With COSPAR's support, CORBES aims to answer critical questions about wave-particle interactions and radial transport within Earth's radiation belts, marking a significant advance in space science. Two scientific papers on CORBES's technical design and goals have been submitted to *Advances in Space Research*.

The comprehensive data from CORBES is expected to aid in the development of predictive models and improve our understanding of space weather influences on the radiation belt, reinforcing its role as a major tool in Earth's space environment monitoring.

Research Report:Progress of Radiation Belt Exploration by a Constellation of Small Satellites TGCSS/SGRB, COSPAR

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