An Etymological Dictionary of Astronomy and Astrophysics
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Transient → streamers which form when → clumps of particles begin to collapse under their own → self-gravity but are sheared out by → differential rotation. This phenomenon is believed to be the source of → azimuthal asymmetry in → Saturn's → A ring (Ellis et al., 2007, Planetary Ring Systems, Springer).

→ gravity; → wake.

Local disturbances in the ring structure caused by the gravitational influence of embedded satellites. If the satellite (moonlet) is large enough to clear a gap in the rings, the moonlet wakes become edge waves that precede the satellite on the inner edge and trail the satellite on the outer edge. For smaller satellites, the "gap-less" wakes have been nicknamed propellors (Ellis et al., 2007, Planetary Ring Systems, Springer).

→ moonlet; → wake.

1) The track left by a moving ship.
2) A turbulent region appearing behind an object in a fluid which streams around the object, for example behind an aircraft in flight.

Cognate with M.L.G. wake "wake," Nor. dialect vok, O.N. vok, voka "hole in the ice."

Kel, from Tabari kel, kal "trail, track, footprint."