Explore: Annular Theory

like Saturn's, in what became known as the "Vailan theory" or "annular theory". His 1886 "Canopy Theory" proposed that the Earth had been ringed by a toroidal

eclipse, the disk of the Sun is fully obscured by the Moon. In partial and annular eclipses, only part of the Sun is obscured. Unlike a lunar eclipse, which

An annular cutter (also called a core drill, core cutter, broach cutter, trepanning drill, hole saw, or cup-type cutter) is a form of core drill used

Gravitational lenses do not focus like eyeglass lenses, but rather lead to annular shapes called Einstein rings. In October 2017, the LIGO and Virgo interferometer

that there are no conventional wing tips. Closed wing designs include the annular wing (commonly known as the cylindrical or ring wing), the joined wing

bowl-shaped with the exhaust exiting in a ring around the outer rim. In theory this requires an infinitely long spike for best efficiency, but a similar

with "lagoon-island". More modern definitions of atoll describe them as "annular reefs enclosing a lagoon in which there are no promontories other than

Blade element momentum theory is a theory that combines both blade element theory and momentum theory. It is used to calculate the local forces on a propeller

A gear pump uses the meshing of gears to pump fluid by displacement. They are one of the most common types of pumps for hydraulic fluid power applications

schoolteacher, in his 1912 work The Earth's Annular System, extrapolated from the nebular hypothesis what he called the annular system of Earth history, with the