On the moon, gravity is so low that with every step the astronauts took they hopped off the ground. Since Mars more massive than the moon but still half the size of Earth, how would gravity affect walking on Mars?
You’d weigh more than on the moon, but less than on Earth. You’d probably feel a little lighter, but not that much.
–Providing highly specific answers since 2000
To be somewhat more specific, surface gravity on Mars is 0.377 that of Earth.
…So a person who weighs 150 pounds on Earth would weigh about 56 pounds on Mars.
.377? I was thinking more like .80. Huh. Shows what I know, I guess.
… and the Moon’s gravity is roughly 1/6 or that of Earth.
(I say roughly because I took the number from a kids science website)
Figuring surface gravity can lead to some surprising results. (And I certainly didn’t calculate any of this out; I just Googled.)
Looking at the physical data for the planets, Mars is slightly over half of Earth’s diameter, but has only a bit more than 10% of Earth’s mass. Even if Mars were as dense as Earth, it would only have around 15% as much mass–mass varies according to the cube of the radius, so an object of equal density and exactly half the diameter will have 0.5 x 0.5 x 0.5 or 12.5% of the first object’s mass–and on top of that Mars is actually only about 70% as dense as Earth.
However, surface gravity is proportional to the object’s mass divided by its radius squared. So, Mars’ lower radius actually has the effect of making its surface gravity greater. (Conversely, even though Jupiter is over 318 times as massive as Earth, its “surface” gravity–that is, the gravity at its cloud tops, since Jupiter doesn’t really have any known “surface”–is “only” 2.364 times that of Earth, because an object at the top of Jupiter’s clouds is so much further away from the center of all that mass than an object on the surface of Earth is from the center of Earth’s mass.)
One thing I always think about when the subject of terraforming mars comes up is that if we can get the air pressure up to 10 psi or more, small pedal-powered aircraft would work quite well in the low gravity. Remember when the human-powered Daedelus aircraft flew across the english channel?
They hopped because walking was dam near impossible with the spacesuits. The hop was intentional and it was not a normal walking step that propelled them off the ground.
To distill MEBuckner’s post a bit, surface gravity is proportional to density times radius. So a planet (Mars) with half the Earth’s radius and about 70% of Earth’s density would have a surface gravity of about 35% of Earth. Which is about right for Mars.
That means that it would be really easy to climb the pyramids on Mars . . .
Heavy spacesuits are required on Mars. Hence, walking would be greatly affected.
If you ever make it up there, you can stay at my timeshare:
"The MarsShop webserver is soley dedicated to the sale of extraterrestrial properties on the planet Mars. It therefore only contains information relating to Mars. For all general information regarding extraterrestrial properties, please check out the brandnew and hot "
insert the ol’ rolleyes here…