Jess (falconry) course of the spring/summer moult, when they are generally re-oiled and serviced as necessary. Jess (falconry) A jess (plural "jesses") is a thin strap, traditionally made from leather, used to tether a hawk or falcon in falconry. Jesses allow a falconer to keep control of a bird while it is on the glove or in training, and allow a bird to be secured on a perch outside its aviary. Jesses come in various types: Jesses are generally made from strips of leather as thin as possible, for which purpose kangaroo leather has become increasingly popular over the years, as it
Momentum exchange tether than the orbital velocity of the tether and the upper endpoint is moving faster. The word is a portmanteau derived from the words "rotor" and "elevator". If the tether is long enough and the rotation rate high enough, it is possible for the lower endpoint to completely cancel the orbital speed of the tether such that the lower endpoint is stationary with respect to the planetary surface that the tether is orbiting. As described by Moravec, this is "a satellite that rotates like a wheel". The tip of the tether moves in approximately a cycloid, in which it is momentarily