Study the interaction between the plasma in Low Earth Orbit and a small satellite

What is it about?

Resident objects in the Low Earth Orbit (LEO) can experience drag not only because of neutrals, but also from the charged particles such as O+, H+, He+, N+. The relative abundance of these ions varies with latitude, altitude, and time. It is unclear how much variation in drag can a satellite experience from these density variations. In this paper we share results from systematic numerical experiments to study the variability of drag experienced by a cylindrical object with a surface potential of -50V in LEO. We show that the drag coefficient can vary by an order of magnitude depending on the location and time in LEO.

Featured Image

Photo by NASA on Unsplash

Photo by NASA on Unsplash

Why is it important?

With the rapid and unprecedented growth in the number of satellites launched into the Low Earth Orbit (LEO) and increasing the risk of collisions, it is important to precisely predict their motion. Between the non-gravitational forces acting on a satellite, the aerodynamic interactions with the residual atmosphere are the largest. However, despite years of research our understanding of the drag generated by charged particles in the ionosphere is incomplete. Charge buildup, quite frequent on modern satellites, can lead to increased electrostatic interactions, which can disturb the flow creating a drag force an order of magnitude higher than predicted by classical approach based on momentum exchange with neutral particles.

Perspectives