Countless Satellites Adjust Their Orbits Due to Solar Flare-Up's Aggressive Eruptions
The Sun is currently in its solar maximum, a phase characterized by numerous solar eruptions and a release of charged particles directed towards Earth. These eruptions have a notable impact on satellites in Earth's lower orbit, leading to unexpected shifts in their positions.
In 2022, Earth was hit by two significant geomagnetic storms triggered by solar eruptions. These geomagnetic disturbances affected the orbits of numerous satellites, leading to an unprecedented relocation of spacecraft, as mentioned by William Parker, a researcher from the Massachusetts Institute of Technology, during a conference at the American Geophysical Union, as reported by SpaceNews.
Geomagnetic storms are disruptions in Earth's magnetic shield—a vast magnetic field surrounding our planet—which are caused by solar wind. In May of the same year, Earth experienced a G5, or extremely intense, geomagnetic storm due to substantial expulsions of plasma from the Sun's corona. This was the first G5 storm to hit Earth in over two decades, resulting in some negative effects on Earth's power grid and breathtaking auroras observed worldwide.
The G5 storm boosted the atmospheric density in lower Earth orbit by up to an order of magnitude, subsequently increasing atmospheric drag. This, in turn, affected satellite movements, according to Parker. The resulting satellite relocation was particularly noticeable in SpaceX's Starlink constellation, consisting of over 6,700 satellites in lower Earth orbit.
"SpaceX recorded a 20-kilometer [12.4-mile] position error in their one-day calculations," Parker was quoted saying in SpaceNews. "If we're uncertain about the position of our spacecraft by 20 kilometers, then collision avoidance becomes virtually impossible." The researcher's comment referred to the threat of collisions between satellites in lower Earth orbit, a danger that is usually mitigated through precise tracking of orbital spacecraft positions. Even a slight shift in orbits can significantly increase the risk of collisions.
Shortly after the storm peak, several satellites performed automated maneuvers to return to their original altitudes, thus adjusting the changes caused by the event. On the following day after the storm, approximately 5,000 satellites, primarily from Starlink, executed orbit-raising maneuvers, as per Parker.
"This is half of all active satellites deciding to maneuver at the same time," he stated. "This is the largest mass migration in history." These maneuvers make it even more challenging to predict the location of satellites relative to one another, further increasing the risk of collisions.
Scientists are still investigating the Sun's behavior to improve their forecasting capabilities for future geomagnetic storms. Understanding these storms would help satellite operators prepare their space hardware more effectively.
The increase in atmospheric density during the G5 geomagnetic storm was attributed to technology deployed in space, such as satellites, making it crucial for scientists to enhance their forecasting abilities using advances in technology and science. In light of the future solar maximum, mitigating the risks of satellite collisions in lower Earth orbit becomes a significant concern for space exploration and communication.
