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AsteriaStar
Relativity

Length Contraction

The relativistic shortening of an object along its direction of motion as seen by an observer it moves past, becoming dramatic near the speed of light. It is the companion of time dilation, and it explains how short-lived muons created high in the atmosphere by cosmic rays still reach the ground.

Highlights

  • Fast-moving objects shrink along their motion

Across fundamental physics

Knowledge connections

Sources

The primary and reference sources this topic draws on.

  • NASANational Aeronautics and Space Administration

    Mission data, planetary science, space telescopes, and public-domain imagery.

    Most NASA-produced imagery is in the public domain; individual items are checked for usage terms before publication.