FYI, here is a link to an ESA web page, summarizing a little study that several of us did a year or so ago, on the topic of the effects of solar radiation pressure on the orbits of SPS’s in GEO, and the possibility of using SRP to aid in station-keeping there (looking to reduce the station-keeping propellant requirements):
https://nebula.esa.int/4000137232
You can download the executive summary of the report from there; we’re looking into putting the main report up on the web as well, and/or presenting the work at some conference.
Oops! We forgot to name the authors of the work, in the report! The authors are Steve Horvath, Kieran A. Carroll, and Henry Spencer.
An important finding, is that SRP will perturb the orbit of an SPS is GEO very significantly; it does that for GEO commsats as well (which GEO commsat operators have known all about for many years), but due to a much higher area/mass ratio, the effect is much more pronounced for an SPS. We were hopeful that SRP cold be used to completely eliminate the need for stationkeeping propellant; sadly that’s not achievable. But it can help somewhat.
This assumes that SPS’s in GEO would have their orbits controlled the same way that GEO commsats do --- north/south and east-west station-keeping, to stay within an assigned box. The SRP perturbation effect forces that box to be quite a bit larger than usual. This suggests that an alternative form of constellation orbit design is needed for operational SPS’s --- we have some ideas about that, and may pursue those further.
- Kieran