Speed of Light
Contents
Speed of Light / Lightspeed
Is the distance (299,792,458 metres) that light travels in a vacuum in one second. Light traveling through an object will travel slower than 1 light second.
Exact values and Comparisons (from Wikipedia)
Metres per second 299,792,458 Planck units 1
Approximate values
kilometres per second 300,000 kilometres per hour 1,079 million miles per second 186,000 miles per hour 671 million astronomical units per day 173 Approximate light signal travel times Distance Time one foot 1.0 ns one metre 3.3 ns one kilometre 3.3 μs one statute mile 5.4 μs from geostationary orbit to Earth 119 ms the length of Earth's equator 134 ms from Moon to Earth 1.3 s from Sun to Earth (1 AU) 8.3 min one parsec 3.26 years from Proxima Centauri to Earth 4.24 years from Alpha Centauri to Earth 4.37 years from the nearest galaxy (the Canis Major Dwarf Galaxy) to Earth 25,000 years across the Milky Way 100,000 years from the Andromeda Galaxy to Earth 2.5 million years from the furthest observed galaxy to Earth 13 billion years
