Nerd meme. Took me a minute.

[HKShooter65]

 

[Lunyfringe]

I got it right away... doppler effect.

Known in astronomy as "blue shift"

 

[HKShooter65]

I got it right away... doppler effect.

Known in astronomy as "blue shift"

Precisely....with a caveat.

In the astronomic world there is not a demonstrable "blue shift" as everything is moving away from everything so it's a red shift. In this hypothetical case the automobiles would be approaching one another, relatively.

Edwin Hubble recognized that the universe is expanding (moving away) by first documenting the red shift of the spectral Fraunhofer absorption lines from calcium atoms way way out there.

Never before heard of a blue shift before, as it's the converse of the oft-mentioned "red shift", but I saw that sticker on a car strolling on Barton Springs in Austin Sunday.

Everything happens for a reason. We call that reason physics.