Which Planet Orbits our Sun the Fastest?

-- | January 14, 2016

Question: Which planet in our solar system is orbiting the sun at the fastest speed?  — Mike

Answer: Mercury is the winner at an orbital speed of about 47.87 km/s (107,082 miles per hour), which is a period of about 87.97 Earth days.  Just for your information, here is a list of the orbital speeds (and periods) for all 8 (plus Pluto) planets:

  • Mercury: 47.87 km/s (107,082 miles per hour), or a period of about 87.97 days
  • Venus: 35.02 km/s (78,337 miles per hour), or a period of about 224.7 days
  • Earth: 29.78 km/s (66,615 miles per hour), or a period of about 365.256365 days
  • Mars: 24.077 km/s (53,853 miles per hour), or a period of about 686.93 days
  • Jupiter: 13.07 km/s (29,236 miles per hour), or a period of about 11.86 years
  • Saturn: 9.69 km/s (21,675 miles per hour), or a period of about 29.42 years
  • Uranus: 6.81 km/s (15,233 miles per hour), or a period of about 83.75 years
  • Neptune: 5.43 km/s (12,146 miles per hour), or a period of about 163.72 years
  • Pluto: 4.74 km/s (10,603 miles per hour), or a period of about 247.92 years

Jeff Mangum