Skip navigation

Gravity Probe B

Testing Einstein's Universe

Special & General Relativity Questions and Answers

If a marshmallow traveled at 99.99 percent the speed of light hit the Earth, what would happen?

The relativistic factor is:

   gamma =  -------------       = 70.7
                       2  1/2
            ( 1 - (v/c)  )

and the total energy is then
  E = gamma x m c

A marshmallow weighs about 10 grams, so the total energy is about 70.7 x 10 x ( 30,000,000,000)^2 = 6.4 x 10^23 ergs. I think this is equal in energy to a few dozen good-sized hydrogen bombs. It makes a mess on the surface, but has no effect on the orbit of the earth.

Please, do not attempt this experiment yourself. Consult professionals first!!

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.