What effect does the Moon and Sun have on gravity?

Question

I know that every object has a gravitational pull regardless of how far or how small it is. It's just that generally this force is negligible.

Does the force produced by the sun and moon have any non-negligible effect on the gravity we experience on earth? I imagine the two most extreme cases would be when the sun and moon are both directly overhead or directly below.

I imagine that all the other planets have far less of an impact than the sun and moon right?

If you mean to ask the effect of moon on the gravitational interaction between earth and sun ( or vice-versa); the answer is-no difference at all. — GRrocks, Mar 26 '16 at 14:50
Possible duplicate of Are we slightly lighter during the day and slightly heavier at night, owing to the force of the Sun's gravity? — Floris, Mar 26 '16 at 16:43

score 1 · Answer 1 · answered Mar 26 '16 at 15:17

Non-negligible depends upon sensitivity of measurement. If you mean non-negligible by human experience of gravity, then that also depends upon individual. Some people feel just different on a full moon night/day. I do not see any other reason than gravity (mostly), or moon light (to some extent). However, humans do not experience the difference in gravity itself, because, the change is small, and gradual. They just feel different. The actual difference in gravity can be easily quantified.

Tides obviously are not negligible in terms of observation (not feeling). Sun and moon both play role in tides. Sun's is much smaller.

Otherwise, For most practical purposes, No.

RedGrittyBrick · Accepted Answer · 2016-03-26T19:23:33.300

Does the force produced by the sun and moon have any non-negligible effect on the gravity we experience on earth?

We know the force you feel is

$$ F = G \frac{m_1 m_2}{r^2}$$

Where

$G$ is the gravitational constant $6.674×10^{−11} N⋅m^2/kg^2$
$m_1$ is your mass, let's say 70 kg.
$m_2$ is the mass of the Earth, Moon or Sun.
$r$ is the distance between the centre of you and the centre of the Earth, Moon or Sun.
$F$ is the resultant force in Newtons.

When I plugged the above into a spreadsheet I got this result

You should note that the value of r for Earth depends on whether you are standing on the equator, at a pole, or somewhere in between, and whether you are at sea level or at the top of a mountain. The variation in force you feel from the Earth when you move a few hundred kilometers horizontally is likely to be greater than the variation caused by the change in direction from you to the Sun or moon.

What effect does the Moon and Sun have on gravity?

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