posted on May, 17 2006 @ 03:43 PM
I think the statement is best posed like this:
Subtract everything from the solar system except the Sun and Earth. The Earth rotates around the Sun, creationists be damned, because of the
gravitational pull of the Sun. The earth also has it's insignificant-when-compared-to-the-sun gravitational pull. Now, there is some high-end
fireworks and the sun dissapears from sight. Poof. Gone. No longer a factor. Now, people on earth will not know this for several minutes, because it
takes light that long to reach Earth.
Now, what happens to the Earth's Orbit in that time? The orbit, that is, which is caused by the sun's gravitational well. Will, when the sun is
taken out of the equation, the Earth jump out of it's orbit at a tangent heading the instant the sun dissapears? Or will it continue in the same
orbit forever? General relativity states that Velocity of Gravity = Velocity of Light. As soon as the last photon reaches earth, the planet will jump
Another way to put it is a model of spacetime, which is actually a circle of rubber held at the edges. Put a pea at one end, representing earth, and
pinch down the very center, representing the sun's graviational well. Release said Sun, and the rubber will, expectedly, shoot straight back up,
causing the pea to jump out of it's place.
This is the first (?) measurement of the speed of gravity, and they present the SoG as being .8 to 1.2 times the speed of light. Going back to our
model of the Earth and sun, their presentation says that the Earth will jump orbit a little sooner or later (Or at the exact same time) than light
reaches earth. There's room for interpretation.