Hi all. I'm a run-of-the-mill layman—not a student. I've just developed an interest in physics lately and have been watching/reading a lot pop physics. So hopefully my question's not too stupid and hopefully the answer's not too far over my head. My question is about the thought experiment where one observer sees a super-train pass by at super-train speed. As it goes by, two lightning bolts strike simultaneously (from the first observer's reference frame) on each side of the train car. A second observer riding in the car sees two non-simultaneous lightning strikes, in his or her reference frame. I think I get the gist of why their reference frames produce different experiences as to when the lightning strikes occur, but what I'm a little unclear on is why the observer on the train wouldn't register a blue shift in the light emitted from the first strike and a red shift in the second. The train is moving relative to the lightning (or from the other point of view, the lightning is moving relative to the train), so why is their no Doppler effect? Thanks for the help!