One of the neat calculations you can do with the Moon is how fast you’d have to travel on its equator to see the Sun sit still, that is the velocity of its spin at its equator. The answer is 10.3 miles per hour which is easy enough to do with a fast walk!
One of the neat calculations you can do with the Moon is how fast you’d have to travel on its equator to see the Sun sit still, that is the velocity of its spin at its equator. The answer is 10.3 miles per hour which is easy enough to do with a fast walk!
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I never thought of it that way. 10 mph is pretty fast. Let’s see, the Moon rotates once on its axis with every orbit around the Earth, keeping the same side facing the Earth. So if you can match the rotation rate, you can stay in the sunlight.
C = πD, where D is the diameter of the Moon.
C = π⋅(2,158) = 6,779.557 miles. C/29.5 = 229.8 miles/day.
229.8/24 hours = 9.58 mph.
You would have to adjust more to the east on the surface of the Moon to account for the Earth’s orbit around the Sun. Here, add one additional rotation of the Moon.
C/365.25 days = 18.56 miles/day.
18.56/24 hours = 0.77 mph. 9.58 + 0.77 = 10.35 mph. You are correct.