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ck2 • today at 1:41 PM • 1 reply • view on HN

could LEO sats have pitot tubes? would they work at ultra-low drag?

my Stryd has a pitot tube and can detect 1mph wind fairly accurately

some advanced drones also have pitot tubes

* https://en.wikipedia.org/wiki/Pitot_tube

* https://store.3dr.com/pitot-tube-set/


Replies

echoangle • today at 9:37 PM

I don’t think so, the pressure you’re measuring would be extremely small. The air at that altitude is acting as a free molecular flow, there’s not a lot of molecules that exert pressure. I think you would need some exotic detector that essentially can detect individual molecules hitting the surface, the pressure itself is tiny.

Maybe the sensor types used for ultra low vacuums could detect the pressure, but I’m not sure if you could gather enough molecules in a front facing tube to get a pressure increase over ambient.