On October 21, 1983, the length of the meter was adjusted. Originally defined in 1795 as one ten-millionth the distance from the Equator to the North Pole, the measurement went through a series of refinements as scientific knowledge advanced. Finally, in 1983, the International Committee for Weights and Measures redefined the meter as “the distance travelled by light in a complete vacuum in 1/299,792,458th of a second.”

The meter is a standard unit of length in the International System of Units (SI), the system of measurement used throughout most of the world. A meter is equivalent to 3.3 feet in the United States customary units, the system used in the U.S.

adjust
Verb

to change or modify something to fit with something else.

Noun

imaginary line around the Earth, another planet, or star running east-west, 0 degrees latitude.

equivalent
Adjective

roughly equal or the same as something else.

measurement
Noun

process of determining length, width, mass (weight), volume, distance or some other quality or size.

Noun

fixed point that, along with the South Pole, forms the axis on which the Earth spins.

vacuum
Noun

area of empty space.

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