Earth's Velocity to Knot

Earth's orbital velocity around the Sun is approximately 29,765 m/s (29.8 km/s), the speed at which our planet travels through space.

v = 2πr/T where r is Earth's orbital radius (~150 million km) and T is one year. Result: ~29.8 km/s.

To km/h: × 3,600. To mph: × 66,600. 29.8 km/s = 107,280 km/h = 66,660 mph.

Interplanetary mission Δv calculations, understanding Earth's motion, and cosmic velocity references.

We're all traveling at ~30 km/s around the Sun right now. In one second, Earth moves 30 km — about 19 miles!

Forgetting about Earth's motion when calculating interplanetary trajectories — it provides free velocity!

~30 km/s around the Sun. We travel 940 million km per year at this speed. Missions to other planets add/subtract from this.

A knot is one nautical mile per hour, where a nautical mile equals exactly 1,852 meters. It's the standard speed unit in maritime and aviation contexts.

1 knot = 1 nautical mile/hour = 1,852 m/h = 1.852 km/h = 0.514 m/s. One nautical mile = 1,852 meters exactly.

To km/h: × 1.852. To mph: × 1.151. To m/s: × 0.514. To ft/s: × 1.688.

Ship cruising speeds (cruise ships: 20–25 knots), aircraft speeds (Boeing 747: 490 knots cruise), wind speed in aviation weather reports (METAR), and sailing.

Fastest ship: 60+ knots (naval vessels). Blue whale swim: 5–20 knots. Jet stream winds: 80–140 knots. Hurricane-force winds: 64+ knots.

Saying 'knots per hour' — incorrect! A knot already includes 'per hour.' Just say 'knots.' Also, confusing nautical and statute miles.

1 knot ≈ 1.85 km/h. Roughly: 10 knots ≈ 20 km/h. Remember: knots are for sea and sky, km/h and mph are for land.