ESA funds space weather satellite swarm to understand and combat orbital debris

By Katyanna Quach,
Published by The Register, 6 October 2023

The European Space Agency has funded a mission to launch a fleet of satellites that will help scientists study space weather and how it can increase debris orbiting our home world.

The project, dubbed ROARS – Revealing the Orbital and Atmospheric Responses to Solar activity – involves 26 research institutions across nine countries, including the UK, Germany, Austria, and the US.

The ROARS mission plan calls for the creation of eight microwave-oven-sized cubesats packed with sensors capable of taking measurements of Earth’s atmosphere and magnetosphere, to investigate how space weather events, such as solar flares, affect orbiting satellites.

Such weather events can change the atmosphere in near-Earth space, and thus the atmospheric drag our satellites experience, eventually causing those sats to move out of their intended orbits. As the project put it, space weather can “heat our upper atmosphere and play havoc with spacecraft trajectories.”

Here’s the crucial part: When sats shift, they can collide with other objects, creating debris that in turn strikes other satellites, creating a cascade of increasing debris and chaos, a situation dubbed the Kessler Syndrome. If that were to happen, with loads of bits of machinery swirling our world, it will be way more difficult to successfully operate birds in Earth’s orbit, or even travel out into space from our planet in one piece.

The exponentially increasing number of satellites mean that the risks are also exponentially increasing

“Until now satellite operators were content to mitigate [satellite collision risks] through additional shielding, and extra fuel for collision avoidance,” Ravindra Desai, the mission’s principal investigator and assistant professor at the University of Warwick’s Centre for Fusion, Space and Astrophysics in England, told The Register.

“The exponentially increasing number of satellites mean that the risks are also exponentially increasing, and more needs to be done to find a deep rooted understanding of the problem and solution as opposed to superficially treating the effects.”

The key to that, Desai and his colleagues believe, lies in studying the relationship between space weather and space debris.

They therefore want the ROARS cubesats to take measurements that reveal how atmospheric densities respond to solar flares and alter satellites’ orbits. The data can then be used to model and predict how spacecraft orbits will change during space weather events, and perhaps inform space agencies and companies how to avoid collisions with other satellites or space junk.

“We also want to measure the magnetic fields and plasma properties. When solar storms hit the earth’s magnetic field, they induce current systems which flow through our atmosphere and cause the aurora. These large currents also heat our atmosphere and increase satellite drag,” Desai explained.

See: Original Article