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Question
The star nearest the Earth is Proxima Centauri, located at a distance of about 4.2 light years. If one could travel there at 99% of the speed of light, what would be the apparent distance to the star?
Dear Cody,
there is nothing in the answer to your question that would require more that putting numbers into equations readily available on the Internet. See for example http://en.wikipedia.org/wiki/Special_relativity#Time_dilation_and_length_contrac...
for relativistic length contraction
L' = L/gamma, where gamma = 1/sqrt(1-(v/c)^2)
for v=0.99c you have gamma = 7.089 (keeping extra decimal points to avoid rounding error till the end) and that leads to
L' = 4.2ly/7.089 = 0.59ly
No tricks. Cheers!
Daniel
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Daniel Mazur
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