What kind of force would be needed to push the Moon into the Earth?

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Discussion Overview

The discussion centers on the theoretical forces and conditions required to alter the Moon's orbit such that it would eventually collide with the Earth. Participants explore various aspects of gravitational interactions, orbital mechanics, and potential external influences from other celestial bodies.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant expresses uncertainty about gravitational effects on celestial bodies and seeks to understand the necessary force to alter the Moon's orbit.
  • Another participant emphasizes that the duration and direction of the applied force are critical factors, rather than the force itself.
  • A participant speculates on the potential influence of orbital resonances from Venus, Mars, and Jupiter on the Moon's trajectory, noting a lack of evidence for calculations on this topic.
  • One participant presents a formulaic approach, stating that the force required to push the Moon into the Earth involves considerations of mass and acceleration, and suggests that energy requirements should be expressed in Newton-meters per second.
  • Another participant questions the likelihood of orbital resonances causing harm, arguing that the Moon has remained stable in its orbit for billions of years without collision.
  • A later reply notes that even without a collision, a change in the Moon's orbit could lead to significant tidal effects, potentially causing flooding and climate changes.

Areas of Agreement / Disagreement

Participants express differing views on the feasibility and implications of altering the Moon's orbit, with no consensus reached on the specific forces or mechanisms that could achieve this. Some participants propose theoretical scenarios while others challenge the likelihood of such events occurring.

Contextual Notes

Participants acknowledge various assumptions regarding gravitational interactions and the stability of the Moon's orbit over geological timescales, but these remain unresolved within the discussion.

AJKing
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I'm not very fluent in how astral bodies are affected be gravity yet, or else I'd punch some numbers myself.

But, what would be needed to knock the moon out of its current orbit and start it on an eventual collision course with the Earth? And what could (theoretically) cause this force?
 
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Well it's not a force that you're concerned with. It depends how long you apply the force, in what direction you apply the force and how big the force is.
 
I'm wondering if a number of coincidental orbital resonances of venus, Mars and Jupiter with the moon could cause some harm.
As yet I can't find evidence on the internet whether someone has done the numbers...
 
F=MA

M=mass of moon.
A=change in velocity per second.

Thus, to push the moon into the earth, 1 Newton of force applied over nearly infinite time would yield nearly infinite acceleration.

The right question is how much energy would be required. Express this in Newton-meters per second.

V(i) = Start with orbital velocity of the moon
V(f) = 0 (stop the moon, it will fall gravitationally into the Earth).

... etc.
 
I like Serena said:
I'm wondering if a number of coincidental orbital resonances of venus, Mars and Jupiter with the moon could cause some harm.
As yet I can't find evidence on the internet whether someone has done the numbers...

I doubt it. At least on the time scale of several billion years. After all, the moon has been around almost as long as the Earth has and there hasn't been a collision yet! And in fact, the moon has been getting further away from the Earth as time passes.
 
Note that the Moon could cause substantial harm without colliding with the Earth. If it were knocked into a different orbit that got much closer to Earth, we'd experience much higher tides which could cause devastating flooding and big climate changes.
 

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