What is the terminal velocity of starship on earth and mars during descent?
Has SpaceX revealed or hinted the values of projected surface area and drag coefficient of the vehicle?
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1$\begingroup$ That'll depend on the ballistic coefficient, wchich will depend on the design, control surface position and mass. $\endgroup$– user20636Commented Dec 10, 2020 at 23:43
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1$\begingroup$ @JCRM And altitude. $\endgroup$– Russell BorogoveCommented Dec 10, 2020 at 23:49
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1$\begingroup$ and weather @RussellBorogove $\endgroup$– user20636Commented Dec 10, 2020 at 23:52
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2$\begingroup$ I'll bet $1.602 \times 10^{-19}$ bitcoin that it's 85$\pm$10% of the terminal velocity of an equivalent right elliptical cylinder of my choosing after the correct answer is posted. $\endgroup$– uhohCommented Dec 11, 2020 at 0:11
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1$\begingroup$ @uhoh I thought about doing the math, but I'd have to guesstimate mass and look up published dimensions and bleaaaahhhhhhh $\endgroup$– Russell BorogoveCommented Dec 11, 2020 at 2:06
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1 Answer
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I have been looking for the same thing. The only mention I found was on a blog post (https://www.neowin.net/forum/topic/1402753-spacex-starship-sn8-15km-test-flight/) which stated 66-68 m/s for SN8. If true, that would imply ± 320 m/s on Mars.
Despite Mars' lower value for g (3.72), the much lower atmospheric density of 0.02 versus 1.2 kg/m3 results in a much higher Vt. This of course assumes that everything else remains constant (mass, area, Cd).
