Of or pertaining to Johannes Kepler or to his works or discoveries.
From → Kepler + -ian a suffix forming adjectives.
Keplerian angular velocity
tondâ-ye zâviye-yi-ye Kepleri
Fr.: vitesse angulaire keplérienne
The angular velocity of a point in a circular orbit around a central mass. It is given by: ΩK = (GM/r3)1/2, where G is the → gravitational constant, M is the mass of the gravitating object, and r is the radius of the orbit of the point around the object.
gerde-ye Kepleri, disk-e ~
Fr.: disque keplérien
A circumstellar disk (such as an → accretion disk or a → protoplanetary disk) in which the → angular velocity at each radius is equal to the angular velocity of a circular → Keplerian orbit at the same radius. The main characteristic of the Keplerian disk is that → orbital velocity varies as r-1/2. This means that an object on an orbit closer to the central mass turns more rapidly than that on a farther orbit. This velocity difference is at the origin of internal friction or kinematic viscous forces between disk particles, which heats up the material.
madâr-e Kepleri (#)
Fr.: orbit keplérienne
The orbit of a spherical object of a finite mass around another spherical object, also of finite mass, governed by their mutual → gravitational forces only.
Keplerian orbital velocity
tondâ-ye madâr-e Kepleri
Fr.: vitesse d'orbite képlérienne
The velocity of an object orbiting another object according to → Kepler's laws.
Keplerian rotation curve
xam-e carxeš-e Kepleri (#)
Fr.: courbe de rotation keplérienne
Fr.: cisaillement keplerien
Shearing motion of an ensemble of particles, each on a nearly circular, → Keplerian orbit. → Orbital velocity decreases as orbital radius increases, yielding shear. Viscous drag on such shear, due to ring-particle collisions, plays a key role in ring processes (Ellis et al., 2007, Planetary Ring Systems, Springer).
durbin-e Kepler, teleskop-e ~ (#)
Fr.: télescope de Kepler
A → refracting telescope which has simple → convex lenses for both → objective and → eyepiece. It suffers from → chromatic aberration, which can be reduced by increasing the → focal ratio. It was first devised by Kepler in 1615.