> At Marian sea level Well thanks for nerd sniping me! This got me googling, and the closest thing to a martian sea level turns out to be super interesting. An

> At Marian sea level Well thanks for nerd sniping me! This got me googling, and the closest thing to a martian sea level turns out to be super interesting. And so I’ll share the interesting stuff I just learned. Since mars doesn’t have a sea, there’s no easy sea level equivalent, so (if I understand correctly) they have a level called the aeroid [0] (the corresponding term for earth’s sea level is geoid. ‘aer’ for Ares, I suppose). At first, this was defined in terms of the level with a specific constant atmospheric pressure, but in 2001, ‘they’ made a new convention based on constant gravitational+rotational potential, since they finally had that data. So now mars ‘sea level’ is that “equipotential [constant potential] surface… whose average value at the equator is equal to the mean radius of the planet.” [1] …Thank you for coming to my ted talk. [0] https://en.wikipedia.org/wiki/Gravity_of_Mars#Areoid https://en.wikipedia.org/wiki/Gravity_of_Mars#Areoid [1] https://en.wikipedia.org/wiki/Geography_of_Mars#Zero_elevation https://en.wikipedia.org/wiki/Geography_of_Mars#Zero_elevati...