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I know this was a science and LEO (low earth orbit) satellite, but here's something to consider when thinking about the difficulties of engineering hardware & software to work together in a satellite.

Geostationary telecom (and weather, and SIGINT, etc) satellites: In the entire history of manned spaceflight no human has ever visited geostationary orbit. Once placed in a geostationary transfer orbit (about 450 x 36,000 km) and then onwards to final geostationary orbit, nobody will ever see a satellite again. The largest ones weigh 6000 kilograms and are the size of greyhound buses. They're out there right now operating with multiply-redundant everything and cost $150 million to build and launch. It is highly unlikely that any time in the next 25 years any human will ever visit one in person or touch one. When a satellite is encapsulated in its fairing/shroud for launch that is the last time anyone will ever see it until its ultimate end of life in hopefully 15 years. Every one of its control systems needs to be so thoroughly debugged and multiply redundant that it can operate out there with absolutely zero chance of repair or parts replacement.




Presumably these satellites are transmitting data back to Earth? Is that channel not bidirectional? If those satellites can be remote reprogrammed, are they really much different than satellites in geosynchronous orbit? Or are you suggesting that satellites in geosync orbit could be manually updated via EVA? I would think that would still be extremely cost-prohibitive (not to mention a huge risk to human life for a weather satellite! Has that ever actually happened?


I'm saying sort of the opposite - there have been very, very rare cases where satellites in LEO were visited by humans and repaired or retrieved, but it's extremely uneconomical (Hubble, LDEF, etc). Actually cheaper to build and launch a new one. But at least it is technologically possible. Whereas nobody has ever gone to geostationary orbit.

There have been proposals for ion engined orbital tugs to grab onto old, out-of-stationkeeping-propellant satellites that still have good electronics, for the purpose of extending their life, or moving them to a new orbital position. But nothing has actually flown.


The moon is beyond geostationary orbit, and I think we've been there ;-)


Particularly, if you don't want to land on the Moon, just go round it and return, then it's easier - you don't need that much propulsion to get back.

But to get to geostationary orbit and stop there, you need rocket power. To get back, you would also need power.


We've been to the moon but humans have never put a manned craft in geostationary orbit, or returned from it - the delta-V requirements are different.


Right, OP wasn't saying that we had never been _beyond_ GEO, but never been to the orbit - going through is a lot easier than stopping off partway.




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