Seriously, any time you have >3 images to stack satellites and planes are a complete non issue. The median pixel value is always going to exclude those. Five images is enough to eliminate any trails even if they overlap between images.
Just do it in space and avoid the whole atmosphere and ground based light pollution. Space is cheaper than ever now, this is a problem for amateur astronomers, and hobbyists shouldn’t hold back progress.
Space imposes extraordinary costs and limitations which heavily precludes exploratory research. Instruments are built for space to achieve specific tasks which we know will be successful.
Instrument development has to first occur on earth-- including the research that lets us know which things will yield results deployed in space.
Astronomy aside, fleets of satellites once they turn to junk may eventually make further launching problematic.
SpaceX deliberately launches satellites into orbits which are too low to sustain on their own. Once the satellites run out of propellant, which happens after a few years of normal operation, they cannot remain in orbit indefinitely and eventually burn up in the atmosphere.
On very rare occasions, a launch malfunctions in such a way that the satellites end up in unintended orbits that do turn into long-term junk, but this is not the norm.
Their performance at cryogenic temperatures is quite good which is one reason why currently in design/construction scientific instruments are still using them.
