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artriant
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- TL;DR Summary
- How much Earth affects the gravity that we feel on the Lunar Surface?
Hello everyone, happy holidays!
Y/day i googled that question (see title), and i found no clear answer, and I was really suprised,
So I had to investigate my self, this is a super basic question,
Let me know if i got this right:
Earth R: 6,371 km
Moon R: 1,737.1 km
d1: 384,400 km (center to center)
d2: 382,663 km (E core to near side)
d3: 386,137 km (E core to far side)
Assuming Earths gravity is 1g, M and E are perfect spheres, orbits are circular, distribution of mass is perfectly uniform, no other forces complicating our system like for example the pull of the sun.
---
A man at the center of the near side of the moon, is standing 60.06 times further away from the Earths CORE compared to a person standing at the surface of Earth. Applying inverse square law we can find that: Earths gravityis 3,488.4 times weaker up there.
Moons surface gravity averaging ~0.166g, the Earths pull is -0.0002772g at that point and has a completely oposite orientation (1.66% in comparison),
Simmilar calculations for the far side of the moon (at the point where Earths and Moons gravitational vectors align): 386,137/3671=60.60|sqr(60.60)=3,673.39|That is: +0.000272g or 1.638% in comparison to Moon Average surface gravity
To put that in perspective a cargo box weighting 1000kg will have an average weigth 166Kg on the Lunar surface,
But at the center of NEAR side it will weight (~1.66% less) 163.24Kg, and (+1.638%)168.72Kg @ the center of opposite side,
Thats a whole 5.48 Kg difference for that container, or 548 grams difference for a man that originally weights 100Kg on Earth
(3.35% icrease in weigth) just because you changed location on the Moon, isn't that crazy considering we just took in account the change due to Earths gravity gradient?
Y/day i googled that question (see title), and i found no clear answer, and I was really suprised,
So I had to investigate my self, this is a super basic question,
Let me know if i got this right:
Earth R: 6,371 km
Moon R: 1,737.1 km
d1: 384,400 km (center to center)
d2: 382,663 km (E core to near side)
d3: 386,137 km (E core to far side)
Assuming Earths gravity is 1g, M and E are perfect spheres, orbits are circular, distribution of mass is perfectly uniform, no other forces complicating our system like for example the pull of the sun.
---
A man at the center of the near side of the moon, is standing 60.06 times further away from the Earths CORE compared to a person standing at the surface of Earth. Applying inverse square law we can find that: Earths gravityis 3,488.4 times weaker up there.
Moons surface gravity averaging ~0.166g, the Earths pull is -0.0002772g at that point and has a completely oposite orientation (1.66% in comparison),
Simmilar calculations for the far side of the moon (at the point where Earths and Moons gravitational vectors align): 386,137/3671=60.60|sqr(60.60)=3,673.39|That is: +0.000272g or 1.638% in comparison to Moon Average surface gravity
To put that in perspective a cargo box weighting 1000kg will have an average weigth 166Kg on the Lunar surface,
But at the center of NEAR side it will weight (~1.66% less) 163.24Kg, and (+1.638%)168.72Kg @ the center of opposite side,
Thats a whole 5.48 Kg difference for that container, or 548 grams difference for a man that originally weights 100Kg on Earth
(3.35% icrease in weigth) just because you changed location on the Moon, isn't that crazy considering we just took in account the change due to Earths gravity gradient?