radius vector

American  

noun

radii vectores, plural radius vectors plural

1. Mathematics. the length of the line segment joining a fixed point or origin to a given point.

2. Astronomy.

   1. the straight line joining two bodies in relative orbital motion, as the line from the sun to a planet at any point in its orbit.

   2. the distance between two such bodies at any point in the orbit.

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radius vector British  

noun

1. maths a line joining a point in space to the origin of polar or spherical coordinates

2. astronomy an imaginary line joining a satellite to the planet or star around which it is orbiting

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radius vector Scientific  

1. A line segment that joins the origin and a variable point in a system of polar or spherical coordinates.

2. The imaginary straight line that connects the center of the Sun or another body with the center of a planet, comet, or other body that orbits it.

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Etymology

Origin of radius vector

First recorded in 1745–55

Example Sentences

Note that the torque vector is orthogonal to both the force vector and the radius vector.

From Textbooks • Mar. 30, 2016

The area covered would always be uniform, because the radius vector would always be uniform in length.

From Aether and Gravitation by Hooper, William George

So Kepler formulated his second great law of planetary motion very simply: the radius vector of any planet describes, or sweeps over, equal areas in equal times.

From Astronomy: The Science of the Heavenly Bodies by Todd, David Peck

But, for physical astronomers, the greatest interest attaches to the reduction of radius vector of Encke’s comet, the splitting of Biela’s comet into two comets in 1846, and the somewhat similar behaviour of other comets.

From History of Astronomy by Forbes, George

Hence the relation between the radius vector and the perpendicular on the tangent of the rolling curve must be identical with the relation between the normal PN and the ordinate PR of the traced curve.

From Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 3 "Capefigue" to "Carneades" by Various