Kilometers Per Second to Knots (km/s to kn)

1 kilometer per second equals 1,943.844492 knots (rounded).

1 kilometer per second = 1,943.844492 knots

How to convert kilometers per second to knots

To convert kilometers per second to knots, multiply the number of kilometers per second by 1,943.844492. The factor is rounded to 10 significant digits. To go the other way, multiply knots by 0.0005144444444 (rounded).

knots = kilometers per second × 1,943.844492

Example: 10 kilometers per second = 19,438.44492 knots.

About these units

Kilometer Per Second (km/s)

ScientificCurrent unit

1,000 m/s. Used for orbital velocities; low Earth orbit is about 7.7 km/s.

Orbital mechanics is where kilometers per second become the everyday scale. A satellite in a circular low Earth orbit between 200 and 2,000 km altitude travels at 7.7 to 6.9 km/s, and the International Space Station and typical low orbit satellites move at about 7.7 km/s, which is 27,700 km/h. Earth itself circles the Sun at an average of about 29.8 km/s, roughly 3.9 times that low orbit speed, since 29.8 divided by 7.7 is 3.87.

The unit also suits escape velocities, such as 11.186 km/s from the surface of Earth and 2.38 km/s from the Moon, and the speed of sound in water, about 1.5 km/s. It is a thousand times the SI base speed of 1 m/s, so quoting orbital motion in meters per second would mean long strings of digits.

1 kilometer per second = 1,000 meters per second (exactly).

Sources: Wikipedia: Orbital speed; Wikipedia: Escape velocity; Wikipedia: Orders of magnitude (speed)

Knot (kn)

NauticalCurrent unit

One nautical mile per hour, exactly 1.852 km/h. The unit of speed for ships, aircraft and wind.

Knots in a rope really were counted. Before the mid-nineteenth century, sailors threw a weighted wooden board, the chip, off the stern on a line called the log-line. The line carried knots at regular intervals, and a sailor counted how many passed through his fingers while another timed the run with a sandglass. William Bourne's A Regiment for the Sea, printed in 1574, is the first known description, and many ships spaced knots 8 fathoms, about 14.6 meters, apart with a glass of roughly half a minute.

Today a knot is one nautical mile per hour, exactly 1,852 meters per hour, about 1.151 mph or 0.514 m/s. A ship making 1 knot along a meridian covers about one minute of latitude per hour, which is why charts and the unit fit together. It is not an SI unit, and the symbol is kn, though kt is common in aviation. Saying knots per hour is wrong, since that would describe acceleration. The US moved civil aircraft standards to nautical miles and knots in 1969, and winds and currents are also quoted in them.

1 knot = 0.5144444444 meters per second (approximately).

Sources: Wikipedia: Knot (unit); Wikipedia: Chip log; NIST Guide to the SI, Appendix B.8: conversion factors

Related conversions

See all speed units.