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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.