orbital velocity

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orbital velocity

The velocity of a satellite or other orbiting body at any given point in its orbit. It is also the velocity required by a satellite to enter an orbit around a body. The orbital velocity, v, is given by the expression
v = √[gR 2(2/r – 1/a )]
where R is the radius of the orbited body, r is the distance from the center of mass of the system (i.e. from the approximate center of the primary), a is the semimajor axis of the orbit, and g is the standard acceleration of gravity. For a circular orbit, r = a and the circular velocity is given by
v = √(gR 2/r )

To escape from an orbit a must tend to infinity and the escape velocity is then given by

v e = √(2gR 2/r )

The orbital period for an elliptical orbit is given by

P = 2πa 3/2/√gR 2

Collins Dictionary of Astronomy © Market House Books Ltd, 2006

orbital velocity

[′ȯr·bəd·əl və′läs·əd·ē]
The instantaneous velocity at which an earth satellite or other orbiting body travels around the origin of its central force field.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
From Figures 10 and 11, it can be seen that the best-fit CDF and the observed CDF of semi-major axis agree better than the case of mean orbital velocity. This should be due to the fact that the p value of the former is 0.9988, which is obviously larger than that of the latter 0.6607.
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* numerically evaluated the orbital velocity, particularly its horizontal components, including the effect of nonlinearity and current;
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