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Gravity Probe B

Testing Einstein's Universe

Special & General Relativity Questions and Answers

What is the momentum of a photon?

The momentum of a photon is simply its energy divided by the speed of light P = E/c. What could be simpler! And it is relativistically correct too!


Return to the Special & General Relativity Questions and Answers page.

All answers are provided by Dr. Sten Odenwald (Raytheon STX) for the NASA Astronomy Cafe, part of the NASA Education and Public Outreach program.