equatorial bulge


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equatorial bulge

n.
The gradual increase of the radius of a planet or star from the poles to the equator, resulting in a deviation from a perfect spherical shape, caused by the object's rotation.
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References in periodicals archive ?
That's how the moon gets its distinctive equatorial bulge.
As tour guides and museum exhibits repeatedly reminded me, archaeological activities continue to reveal more about the people who lived in this part of the Andes, and how much they understood about living at the Earth's equatorial bulge.
If there's no ocean, Pluto should be comparatively flattened at its poles, containing a "fossil" equatorial bulge left over from early in its history, when the body was spinning more rapidly.
Otherwise, the moon's equatorial bulge would have continued to diminish, rather than to have been frozen in place.
These forces include pressure from sunlight, magnetic torques acting on charged dust particles, and the influence of slight variations in gravity due to the equatorial bulge of Saturn.
But as the planet slows down, it causes the equatorial bulge to collapse which puts enormous pressure on the tectonic plates.
On the other hand, a rapidly rotating prolate spheroid seems like a counter-intuitive model, since one would expect centrifugal effects to come into play and force an equatorial bulge to develop.
The centrifugal effect would, in other words, give rise to an equatorial bulge, which would make the diameter across the Equator somewhat longer than the diameter from pole to pole.
A comparison of this model with the planet's known mass, radius, surface temperature, gravity and equatorial bulge implies that Jupiter's core is an Earth-like rock 14 to 18 times the mass of Earth, or about one-twentieth of Jupiter's total mass, according to Militzer.
WHY DOES Saturn's moon Iapetus have a big equatorial bulge and an eerily precise mountain range--the highest in the solar system--running exactly along its equator?
As the spin axis drifts, this equatorial bulge also migrates.