The National Oceanic and Atmospheric Administration (NOAA) announced severe geomagnetic storms impacted Earth on March 24.
Such celestial disturbance not only hampers the functionality of satellites but also undermines services dependent on them, including navigation and communication. As more satellites take to the skies, the impacts of space weather are becoming an increasingly urgent concern according to experts at NOAA's Space Weather Prediction Center (SWPC).
Dr. Tzu-Wei Fang, who leads a group studying the upper atmosphere at the center, warns that major solar storms can significantly disrupt satellite operations through various effects. "We've seen the consequences already with losses like the 38 Starlink satellites downed after a relatively minor solar storm in 2022," said Feng. "As the satellite industry continues rapid growth, safeguarding these spacecraft from space weather will only become more critical."
Satellite operators face several potential issues driven by eruptions of energetic particles and magnetic forces from the Sun's atmosphere. One of the primary impacts is increased atmospheric drag that can dramatically alter the trajectories of satellites in low-Earth orbit.
"When a major storm hits, we see neutral density enhancements of over 100% above 400 km altitude where many satellites operate," Feng explained. "The neutral winds generated can reach 1 km per second, applying significant forces to change orbits unexpectedly."
Another hazard is surface charging on satellite bodies from the charged particle environment. These electrical effects can induce damaging currents in critical electronics. Radiation exposure during solar particle events is also a threat to spacecraft systems and human explorers.
Perhaps most widely felt are the disruptions that space weather can cause to radio signals — including the GPS/GNSS navigation and communication networks that have become integral infrastructure for industries like aviation, agriculture, ride-sharing, and electrical grids.
"The ionosphere fills with irregularities that can refract or obstruct these signals when space weather gets volatile," said Feng. "We work closely with many companies to nowcast and forecast these disruptions, which can seriously degrade system accuracy and operability."
To better understand and predict the complex space environment, Feng's team at SWPC has developed an advanced numerical model called VM-IPE that captures conditions across the whole atmosphere up to 600 km altitude. A major ongoing effort is determining real-time neutral atmospheric density, a key influence on satellite drag.
"We're collaborating directly with companies like SpaceX, ingesting their spacecraft data to inversely derive densities," Feng stated. "It's a great example of the partnerships needed as space weather impacts escalate."
A collaboration known as COSMIC-2 involves Taiwan, NOAA, and the US Space Force (USSF), jointly deploying six remote-sensing smallsats. Discussions are underway to explore the potential for ongoing cooperation with Taiwan in expanding satellite programs focused on weather forecasting, space weather monitoring, and climate research.
Feng, who has collaborated with Taiwan on space weather research, believes Taiwan's space policy and planning need a clear long-term strategy and to carefully consider the global development of the space industry and research. "This might be something that all the agencies and universities in Taiwan can work together."
As the satellite industry soars to new heights, developing environmental intelligence about space weather remains imperative for safeguarding our space-based technology infrastructure.
