FCC lets SpaceX cut satellite altitude to improve Starlink speed and latency

Re:FCC lets SpaceX cut satellite altitude to improve Starlin... by tulsua on Tuesday April 27, 2021 @07:36PM (#26963486)

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).

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Re:FCC lets SpaceX cut satellite altitude to improve Starlin... by MisterBiggs on Tuesday April 27, 2021 @08:09PM (#26963792)

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.

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Re:FCC lets SpaceX cut satellite altitude to improve Starlin... by CarVac on Tuesday April 27, 2021 @07:43PM (#26963545)

They do have onboard propulsion.

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Re:FCC lets SpaceX cut satellite altitude to improve Starlin... by hypertele-Xii on Tuesday April 27, 2021 @08:53PM (#26964071)

With limited fuel.

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

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Re:FCC lets SpaceX cut satellite altitude to improve Starlin... by mlindner on Tuesday April 27, 2021 @11:32PM (#26965237)

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

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