UnoChance t1_it4ar1l wrote on October 20, 2022 at 8:48 PM

Reply to comment by [deleted] in China looked at putting a monitoring satellite in retrograde geostationary orbit via the moon by OkOrdinary5299

Doing it in retro would make it near impossible to safely catalog anything. They just want to have the threat of it being there looming.

[deleted] t1_it4c4yo wrote on October 20, 2022 at 8:56 PM

They probably mean just above or below GEO. Such a satellite, equipped with radar, would catalog all satellites & debris in GEO every 12 hours.

UnoChance t1_it4cl9o wrote on October 20, 2022 at 8:59 PM

Well above or below wouldn't work. If you mean further out then that'd be a bad idea since that's where most graveyard orbits are and if you mean closer in then sure that's possible but positions of GEO satellites do not require space-based detection. There is really no point in doing this unless you were operating like gssap

[deleted] t1_it4d9j6 wrote on October 20, 2022 at 9:04 PM

Above as in higher altitude, not a different inclination. If space based detection isn't necessarily, why does the US do it?

UnoChance t1_it4dvw9 wrote on October 20, 2022 at 9:08 PM

"More accurate tracking and characterization of man-made orbiting objects." You can do a lot more at ~0 relative velocity versus ~6 kps though

[deleted] t1_it4ex78 wrote on October 20, 2022 at 9:15 PM

Not necessarily. Taking multiple measurements from different angles can be more useful than sitting still and staring at it all day.

UnoChance t1_it4f5r7 wrote on October 20, 2022 at 9:17 PM

RPO is not a static operation Edit: to expand, that article you sent says that gssap conducts RPO meaning it moves along the belt as you mentioned. Since it is so close it can actually look from more angles in a safer manner than a retro orbit

phryan t1_it5fbwf wrote on October 21, 2022 at 1:43 AM

The relative velocity at GEO altitude but in the opposite direction would be around 6km/s with very brief observation periods which would make determining anything about an object difficult. Going 'with the flow' so to speak would take longer to see everything but relative velocity is lower and longer observation periods, which makes determining an object's orbit much easier.