Astronomy
Relativistic Aberration and Its Effect on Observed Celestial Positions
Quick fact
An observer moving at 25% the speed of light would see a star that is directly ahead appear shifted by about 14 degrees from its true position—a shift far larger than any classical effect could produce.
Why this is interesting
Ever wonder why stars appear to be where they aren't? When you move fast, the universe seems to tilt—and Einstein showed this isn't just an illusion.