physics – Page 8 – National Radio Astronomy Observatory

How Does the Photon Density From a Star Change With Distance?

I believe that your question has been answered on the Physics Stack Exchange. For a star of radius R…

I think what you want to use are two laws of cosines. I believe that the solution to the…

Yes. The speed of light is a fundamental limit to the speed at which any communication signal can travel. …

These two terms are used in multiple contexts throughout the physical sciences, but their most common usage is to…

If you ignore the small variations in the Moon’s orbit (which amount to about 10% of the distance to…

Your calculations are correct in that the Sun is refracted by an amount that is close to its diameter…

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