The debris population at geostationary orbit and the fate of aged spacecraft

My PhD project focuses on the imaging and tracking of space debris in geostationary Earth orbit (GEO), around 36000 km above the equator. Geostationary satellites follow the rotation of the Earth and have the same orbital period, meaning that they appear 'fixed' in the sky. This makes GEOs extremely useful for communications, but space within the belt is very limited. Because of this, the geostationary belt constitutes some of the most expensive real estate available!

Previously, it was thought that the population of debris in GEO would be fairly negligible, since strict regulations are in place to ensure that the satellites are separated by large enough distances. However, the recent apparent destruction of two GEO satellites (AMC-9, Telkom-1) has provided clear evidence that a debris field must exist.

Left: [Credit: Earth Observatory, NASA] This image shows the results of a computer simulation used to track orbits of satellites and a large proportion of debris. Two clusters of objects are apparent. The most obvious of these are the low Earth orbit objects, at altitudes < 2000 km, that can be seen as a crowded sphere in the Earth's nearby vicinity. Also clear are the GEO satellites, which map out a well-defined ring in line with the Earth's equator. Other objects are either in highly inclined orbits, or have served their use and been transfered to a so-called 'graveyard' orbit.

Other research interests

During my undergraduate studies, I undertook three Undergraduate Research Support Scheme (URSS) projects.

Attempted detection of weather patterns on HAT-P-7b	poster
Modelling the circumbinary candidate KOI-1741	poster
Modelling panspermia in the TRAPPIST-1 system	poster

Publications

Veras, D., Armstrong, D. J., Blake, J. A., Gutierrez-Marcos, J. F., Jackson, A. J., Schäefer, H., 2018. "Dynamical and biological panspermia constraints within multi-planet exosystems", Astrobiology, In Press.

Armstrong, D. J., de Mooij, E., Barstow, J., Osborn, H. P., Blake, J., Fereshteh Saniee, N., 2016. "Variability in the atmosphere of the hot giant planet HAT-P-7 b", Nature Astronomy, 1, 0004