Corona discharge with a discharge current of a few hundred microamperes can blow out a small candle flame within about 1 cm of a discharge point. A pinwheel, with radial metal spokes and pointed tips bent to point along the circumference of a circle, can be made to rotate if energized by a corona discharge; the rotation is due to differential electric attraction between the metal spokes and the space charge shield region that surrounds the tips. Corona discharge A corona discharge is an electrical discharge brought on by the ionization of a fluid such as air surrounding a conductor that is
Collis (planetary nomenclature) Venus and 5 on Titan. On different celestial bodies they are named differently: Collis (planetary nomenclature) Collis (plural: colles, from the Latin word for "hill") is a small hill or knob on a celestial body. The term is used in planetary nomenclature: it is a part of international proper names of such features. Like other generic terms, it is capitalized and stands after the proper name (for example, "Bilbo Colles"; the only exception is "Colles Nili" on Mars). As of 2015, only groups of the hills have names, and the term is used only in plural. Like the other terms