>> ... averaging 44 satellites per launch.
How big are these things and how many can _actually_ be put up in a single launch?
>> However, SpaceX intends to use this to their advantage by gradually replacing inactive satellites ...
What happens to inactive satellites? Do they de-orbit themselves in safe locations? Or just stay as space junk?
I believe they plan to use the last bit of their propellant to lower the perigee into the atmosphere, which will then naturally deorbit. They recently submitted documents to the FCC stating a change to materials to ensure everything burns up and wont impact the earth. [1]
[1] https://www.nasaspaceflight.com/2019/03/spacex-higher-necess...
Nice article (the relevant portion is near the end, but if you're interested in this you might as well read the whole thing): https://www.nasaspaceflight.com/2019/03/spacex-higher-necess...
Raw source: https://licensing.fcc.gov/myibfs/download.do?attachment_key=...
44 in one launch is very doable. They’ve done 64 in a launch before: https://www.google.com/amp/s/phys.org/news/2018-12-spacex-sa...
IANASJ (I am not a space junkie) but this makes those ones sound unusually tiny and brings me back to the first question - are the Starlink birds similarly sized?
That being said, no official number has been given out by spacex so this is all guesswork and this article did not cite a source for the "44 satellites per launch".
44 seems very doable, and they'd just burn up like any other satellite.
The plan for active decommissioning is to drop perigee into “atmosphere” but there are also plans for passively deorbiting satellites that fail while in higher orbits which would otherwise take Millenia to de orbit on their own.