> not a problem if they are maintained in the way the SpaceX sats are going to be.

Aka - Not a problem if they are well thought out, well planned, and maintained.

Are there international agreements that specify this is the case? Just curious, real question.

Yeah ditto. And are there agreements to stop them interfering with each other? I get that space is really really big but surely there needs to be a way to coordinate so much stuff up there.

The ITU is the international body that assists with coordination among nations and their satellite systems.

It's a problem for astronomy for example.

Isn't this a solved problem already by putting cameras in space?