Original: As of May 2008 , Voyager 1 was traveling at a speed of 17.1 kilometers per second relative to the sun ( 3.6 AU per year or 38,400 miles per hour or 61 600 km/h ) , 10 % faster than Voyager 2 .
Simplified: As of November 2005 , the spacecraft was travelling at a speed of 17.2 kilometers per second relative to the sun ( 3.6 AU per year or 38,400 miles per hour ) , 10 % faster than Voyager 2 .