Velocity of Sound in Sea Water (20°C, 10m depth) to Kilometer per Second

The speed of sound in seawater at 20°C and 10 meters depth is approximately 1,522 m/s, varying with temperature, salinity, and pressure.

Complex function of T, S, P. Mackenzie equation: c ≈ 1,449 + 4.6T - 0.055T² + 0.00029T³ + (1.34-0.01T)(S-35) + 0.016z. Typical: ~1,500 m/s.

To km/h: × 3.6. To ft/s: × 3.281. 1,522 m/s = 5,479 km/h = 3,404 mph.

Naval sonar, commercial ship echo sounders, underwater positioning systems, and marine seismic surveys.

Sound speed increases ~1.3 m/s per °C, ~1.3 m/s per PSU salinity, and ~1.7 m/s per 100m depth. SOFAR channel at ~1000m depth traps sound for thousands of km.

Using a single constant — sound speed in the ocean varies significantly with depth and location. Always measure or calculate for local conditions.

~1,500 m/s is a good approximation. Remember: warmer, saltier, deeper = faster sound. Critical for accurate sonar ranging.

Kilometer per second measures how many kilometers an object travels in one second. Used for very high-speed phenomena like spacecraft, asteroids, and planetary motion.

1 km/s = 1,000 m/s = 3,600 km/h. There are 1,000 meters in a kilometer.

To m/s: × 1,000. To km/h: × 3,600. To mph: × 2,237.

Earth's orbital speed: 29.78 km/s. Moon's orbital speed: 1.02 km/s. Space shuttle orbital speed: 7.8 km/s. Meteor entry: 11–72 km/s.

Solar system escape velocity: 42 km/s. Voyager 1 speed: 17 km/s. Fastest star (S4714 near black hole): 24,000 km/s (8% light speed).

Underestimating the scale — 1 km/s is 3,600 km/h, extremely fast. Confusing with m/s (1000× smaller).

Think of km/s as 'space speeds.' Earth orbits at ~30 km/s. To escape Earth: 11.2 km/s. Moon orbit: ~1 km/s.