From the article above:
“If these effects were not properly taken into account, a navigational fix based on the GPS constellation would be false after only 2 minutes, and errors in global positions would continue to accumulate at a rate of about 10 kilometers each day! The whole system would be utterly worthless for navigation in a very short time.”
That’s a pretty significant relativistic error. Einstein would be happy to know that it’s thanks to him our GPS works.
When a jet goes the speed of sound, or faster, the sound it makes cannot project out in front of it. The sound builds up, rolls off the side and creates a sonic boom.
So if you could go the speed of light, a light shining forward would not be able to project out in front of it, so the light would build up and roll off the sides and create a light boom.
Thats my theory and I’m sticking to it. 
that s what happens on star trek…
Spaceballs had a better explanation, we’ve gone to plaid! @keith is the speed of light from a headlight diminished (keeping it car) by 1000 mph at the equator(the speed of earths rotation)? Would that apply to the speed of sound? Thunder before you or after you? 2 many questions.
Barkydog, that depends on whether the car is pointing east or west. Now stop asking these technical questions, you’re making my brain hurt.