The Korea Astronomy and Space Science Institute (KASI) and the Korea Aerospace Research Institute (KARI) jointly developed the small satellite "Doyosat," which successfully captured changes in the space environment around Earth despite powerful solar storms.
KASI noted that it successfully collected plasma change data in the ionosphere during the super solar storm that occurred last May using the Doyosat satellite group. The ionosphere extends from 60 to 1,000 kilometers above the Earth, where some atmospheric particles are ionized by energy from the Sun, creating plasma that affects radio signals. Plasma refers to a state where electrons have detached from atoms.
Doyosat consists of four cube satellites, each weighing less than 10 kilograms, and was launched into Earth orbit via the Korean rocket Nuri in May 2023. The primary mission of Doyosat is to observe near-Earth space weather that causes errors in the Global Positioning System (GPS) or communication disruptions.
Solar storms are phenomena that occur when powerful particles and magnetic storms from the Sun affect Earth. This observation took place during last year's solar storm, which was the strongest since 2003. At that time, auroras were observed worldwide, including in Korea, generating significant interest. When high-energy particles from the Sun collide with the Earth's upper atmospheric magnetic field, they create auroras that light up the sky.
The powerful solar storm also caused significant changes in the electron distribution and plasma density of the ionosphere near Earth. Doyosat captured the "equatorial ionization anomaly phenomenon," where maximum density plasma moved from the equator to a magnetic latitude of 40 degrees due to the solar storm. This phenomenon can cause GPS errors, communication disruptions, and even damage to power grids. Simultaneously, Doyosat satellites showed that, during this period, their orbits had descended on average by about 200 to 500 meters.
Lead researcher Lee Jae-jin said, "As the first research result using observation mission data from domestic cube satellites, it is significant that we launched a domestically developed satellite using our technology and published the research results in a global academic journal." He also noted, "Based on our experience from observing Doyosat for more than two years, we are promoting the 'ultra-low-altitude Doyosat-2' project for follow-up research."
In particular, Doyosat performed independent observations in the dawn-dusk orbit at an altitude of 500 kilometers, which is often difficult for other foreign satellites. KASI explained, "Its reliability is comparable to data from overseas large satellites such as the U.S. Department of Defense's Defense Meteorological Satellite Program (DMSP) or the European Space Agency's Swarm satellites."
This research result was published in the international journal "Space Weather" on 26th.
References
Space Weather (2025), DOI: https://doi.org/10.1029/2025SW004470