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by tulsua 1879 days ago
I wonder how long they'll stay up for. With the lower orbit, I suspect they'll have a short lifespan (unless they have a motor onboard to push them along).
2 comments

Using a pretty simple atmospheric model going from the original 1,325 km to the newest 540 km altitude, the air density doubles (1.990x).

Then there's the increase in velocity since the orbit is now smaller, which is about 300 m/s.

So overall the drag force doubles, but there's no way to tell how long the lifespan is without knowing a coefficient of drag and using a much more complicated atmospheric model that takes into account things like Sun and geomagnetic activity.

They do have onboard propulsion.
With limited fuel.

Electric flywheels can only alter the attitude (orientation) of spacecraft, not its orbit. For that you need fuel.

Yes but they're argon based ion thrusters which can last a long long time.