Electrostatic levitation
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Electrostatic levitation is the process of using an electric field to lift a charged object and counteract the effects of gravity. It was used, for instance, in Millikan's oil drop experiment and is used to suspend the gyroscopes in Gravity Probe B during launch.
Due to Earnshaw's theorem, no static arrangement of classical electrostatic fields can be used to stably levitate an object. There is a point where the two fields cancel, but it is unstable. However, it is possible to use dynamically changing electric fields to hold an object in position.
On the moon the photoelectric effect charges fine layers of dust on the surface forming an atmosphere of dust floating over the surface of the moon.
See also
External links
- http://esl.msfc.nasa.gov/
- Electrostatic levitation raises dust particles off the surface of the moon (http://www.space.com/scienceastronomy/top_10_weird_list-7.html)
- Hybrid electric/acoustic levitation (http://www.nasatech.com/Briefs/Mar99/NPO20165.html)
- Electrostatic levitation and transportation of glass or silicon plates (http://www.intellect.pe.u-tokyo.ac.jp/research/es_lev/es_lev_e.html)