Measuring Motion

Updated February 21, 2017 | Factmonster Staff

Speed is the measure of motion. You can find it by dividing the distance covered by the time it takes to travel that distance.

Speed of Light

If a star is 10 light-years away, it is about 60 trillion miles distant.

Light travels through space at 186,000 miles per second.


A light ray travels 5.88 trillion miles a year in space.

Star Distance

The star Sirius is 9 light-years away from the solar system.

More Earthly Speeds

  • Cheetah: 70 mph
  • White-tailed deer: 32 mph
  • Human being: 27.89 mph
  • Garden snail: 0.03 mph
  • Fastest automobile: 205 mph
  • Fastest train: 252 mph
  • Fastest helicopter: 249.10 mph
  • Fastest jet: 2,193.167 mph
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