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Sep29-10, 02:02 PM
Sci Advisor
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Quote Quote by Sherv View Post
Hello, Thank you for your posts, unfortunately the debate still rages and qualifications are now being questioned.

Is anyone who has already commented a qualified physicist / mathematician / Scientist etc .. ?

lol sorry to hassle !!
You can find the orbital velocity of the Earth (taking the Earth's mass into account) by the formula:

[tex]V_o = \sqrt{\frac{M_s^2 G}{(M_s+M_e)r}}[/tex]

Ms and Me are the masses of the Sun and Earth respectively, G is the Gravitational constant and r the distance between the Earth and Sun.

Using 2e30kg for Ms, 6e24 kg for Me and 1.5e11 m for r, this gives us an answer of

29828.35336 m/s

Doubling "Me" gives an answer of


about 0.045 m/s less.

Since this is slower than the Earth's present orbital velocity, if it suddenly doubled its mass (and everything else remained the same), the Earth would being moving faster than it needed to in order to maintain its present orbital distance and as a result, would move into a slightly more elliptical orbit with an average distance a little further from the Sun. But only slightly. 0.045 m/s is a pretty small difference, much smaller than the amount the Earth's orbital speed varies due to the eccentricity of its present orbit.