Light travels at a speed of 299,792 kilometers per second; 186,287 miles per second. It takes 499.0 seconds for light to travel from the Sun to the Earth, a distance called 1 Astronomical Unit. below I list the light travel times from the Sun to each planet:

Planet           Distance in AU            Travel time....................................................................Mercury              0.387        193.0 seconds   or    3.2 minutesVenus                0.723        360.0 seconds   or    6.0 minutesEarth                1.000        499.0 seconds   or    8.3 minutesMars                 1.523        759.9 seconds   or   12.6 minutesJupiter              5.203       2595.0 seconds   or   43.2 minutesSaturn               9.538       4759.0 seconds   or   79.3 minutesUranus              19.819       9575.0 seconds   or  159.6 minutesNeptune             30.058      14998.0 seconds   or    4.1 hoursPluto               39.44       19680.0 seconds   or    5.5 hours....................................................................

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