zlacker

>>alden5+(OP)
I sit in my hot tub at night and see 1-2+ satellites go over every single time I'm out there.

Which also makes me wonder how many of the shooting stars I've seen recently are just old starlinks burning up.

>>latchk+Vx5
> Which also makes me wonder how many of the shooting stars I've seen recently are just old starlinks burning up.

Probably close to none. The lifetime of the satellites is about 5 years give or take. According to this page [1], a total of 355 satellites have deorbited over the past roughly 5 years. That's an average of about 71 per year or about one every 5 days.

Since planned disposals are done over uninhabited areas (e.g. the pacific ocean), the likelihood of spotting one is very low.

Hope that helps answer your question, even it wasn't necessarily meant seriously :)

    [1] https://starlinkinsider.com/starlink-launch-statistics/

>>qayxc+oB5
If someone makes a mistake and the satellite deorbits in the wrong place, am I likely to be impaled by a satellite screw or something travelling at terminal velocity?

>>aether+1H5
Actually the person you replied to somewhat incorrectly. They're not targeted re-entries because the on-board propulsion of Starlink is too low to precisely control the re-entry location. However instead the satellites are designed to be intentionally "demisable" meaning that every portion of the satellite should vaporize/turn to char/dust during re-entry.

Put another way, every kilogram of Starlink spacecraft has as much energy "stored" in it's motion as around 4-5 tons of TNT.

>>mlindn+3z6
> Actually the person you replied to somewhat incorrectly. They're not targeted re-entries because the on-board propulsion of Starlink is too low to precisely control the re-entry location.

SpaceX says otherwise, see [1]

   SpaceX spokesman James Gleeson, when asked about the 10 satellites, said SpaceX is “performing a controlled de-orbit of several first iteration Starlink satellites,” using onboard propulsion.  

There's a difference between unscheduled deorbiting (as happened to about 40 satellites after a solar storm in February 2022) and a scheduled deorbiting manoeuvre trigged by ground control. Starlink satellites use electric on-board propulsion (Krypton powered Hall thrusters) that doesn't run out as quickly as chemical or cold gas gas thrusters. There's also not much precision needed to avoid major population centres - Earth is pretty big after all.

[1] https://spacenews.com/spacex-launches-fourth-batch-of-starli...

>>qayxc+qq8
Not quite. The spokesman is a talking about controlled deorbit, where propulsion is used to actively lower altitude rather than coasting down due to atmospheric drag. This is in contrast to controlled reentry, which targets an ellipse on the ground where any debris would fall. The latter requires either much more thrust than their electric thrusters have, or a much steeper reentry angle than Starlink's circular orbits.

Starlink satellites are pretty well aerodynamically balanced when in their "ducked" orientation, but are not going to be able to overcome aerodynamic torques below 200 km or so, meaning they will be unable to point their thrusters in target directions. At that point, there are still 1-2 days before reentry will occur. Hour-to-hour variability in tropospheric atmospheric density due to solar flux levels and geomagnetic activity means that the precise reentry time will be unpredictable to within a few hours (which equates to anywhere along the ground track of a few orbits).