mean distance

American  

noun

Astronomy.

1. the arithmetic mean of the greatest and least distances of a planet from the sun, used in stating the size of an orbit; the semimajor axis.

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mean distance British  

noun

1. the average of the greatest and least distances of a celestial body from its primary

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Etymology

Origin of mean distance

First recorded in 1885–90

Example Sentences

By feel, I mean distance control: the ability to look at a putt, make a few practice strokes, and then put the right amount of hit on it.

From Golf Digest • Feb. 8, 2018

The authority, in its defense, points out that the current rate remains a staggering improvement from 1981, when the mean distance between failures was 7,000 miles.

From New York Times • May 22, 2017

Ms. Hakim said the reliability of trains, known as mean distance between failure, had dropped because it had reached an artificially high level when a large order of new subway cars arrived in 2010.

From New York Times • Feb. 12, 2017

For each planet in our solar system, look up the mean distance from the Sun in AU and the orbital period in years and overplot these data on the theoretical Keplerian curve.

From Textbooks • Oct. 13, 2016

Upon his return there was now enough information for the French astronomer Joseph Lalande to calculate that the mean distance from the Earth to the Sun was a little over 150 million kilometers.

From "A Short History of Nearly Everything" by Bill Bryson