The Shalimar Treaty

[Slick]

Not as of yet, no accurate method for determining gravity really exists. That method sounds to me like it would work, however its effect is very very small. The determination of gravity would obviously have to be a vector; strength and direction and be made extremely accurately such that the error in measurement is small compared to the value.


Since gravity has no maximum range, the earth is also being pulled by everything else in the universe (closer than the age of the universe x the speed of light). Since the force of gravity drops by the inverse square law, effects from mass outside our solar system will probably be too small to detect for a very long time, if ever.

There are other effects too that would affect the results:

Curvature of space - currently postulated, but measurement inaccuracy is far too large compared to numbers that we would need. At least our local section of space is "flat" i.e. not curved to the best of our measurements.

Dark matter - matter that does not give off light. Rocks, dust, gas, etc. Some scientists have postulated exotic forms of mass (wimps - weakly interacting, massive particles), but these too haven't been observed. But dark matter does exert gravitational forces. Based on rotational dynamics in the galaxy, there has to be a huge amount of dark matter; far more than the luminous matter that we can see. Not sure how much is in our solar system; or if it has a significant effect.

"Dark energy" - I really don't want to go there. Possible, but unobserved, and rather controversial. If it exists, though, it could/would affect gravity.

Expansion of space - the exact rate is debated, but it has upper and lower bounds based on observations. I'd have to see the numbers, but my guess is that this is too small to have an effect on our local orbit around the sun.

And of course the catch all - how can we know if there is something else that is currently totally unknown by us???