As a high speed spaceship flies past you, it fires a strobe light that sends out a pulse of light in all directions. An observer aboard the spaceship measures a spherical wave front that spreads away from the spaceship with the same speed c in all directions. What is the shape of the wave you measure?

Question

As a high speed spaceship flies past you, it fires a strobe light that sends out a pulse of light in all directions. An observer aboard the spaceship measures a spherical wave front that spreads away from the spaceship with the same speed  c in all directions. What is the shape of the wave you measure?

jamesj · Answer

The speed of light is c in all frames of reference.  Hence ...

anonymous · Answer

Spherical again ...

jamesj · Answer

The idea that the speed of light *is* the same, a prediction from Electromagnetism, and in all frames of reference was one of the keys to the development of Special Relativity.