Speaker
Description
The number of satellites launched into low Earth orbit (LEO) is increasing at an exponential rate. Launches support deployment of multi-satellite constellations for many applications. In situ experiments with the Canadian Swarm-E Satellite have been conducted to better locate the positions of satellites and space debris for prevention of collisions.
Currently, there are about 27,000 known space objects and over 100 million of unknown pieces of space debris. Collision avoidance requires precise knowledge of the positions for all space objects. New techniques are being developed to detect the small, < 10 cm, objects by the plasma waves they generate in space. The bases for this technique is that all space objects in orbit around the Earth (1) pass through a magnetized plasma, (2) become electrically charged, and thus (3) produce detectable plasma waves [1]. The University of Alaska is working with the University of Calgary to find space debris and satellites moving through these irregularities and can excite plasma emissions such as whistler, compressional Alfven, or lower hybrid waves. Orbital kinetic energy is the source of lower hybrid waves which is converted into an electromagnetic plasma oscillation when a charged space object encounters a field aligned irregularity (FAI). Such whistlers propagate undamped at around 9000 km/s from the source regions and can be detected at ranges of several earth-radii. Laboratory Experiments are being developed using the plasma chambers and lasers to accelerate particles through plasma targets simulating wave generation by charged objects in space. The signature of space objects identified with orbit-driven waves is analyzed with Plasma Dispersion and Poynting Vector theory to determine the angle, range, and physical characteristics of small size space debris.
[1] P.A. Bernhardt, R.L Scott, A Howarth, George. J. Morales (2023) Observations of Plasma Waves Generated by Charged Space Objects, Phys. Plasmas 30, 092106, https://doi.org/10.1063/5.0155454
