Electrostatic levitation

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 Robert 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 a point charges. There is a point where the two fields cancel, but it is unstable. However, it is possible to use static electric fields to hold a sized object in position. For example, system of two equally charged coupled toruses must be stable, even from TOPOLOGICAL considerations.

On the Moon the photoelectric effect and electrons in the solar wind charges fine layers of moon dust on the surface forming an atmosphere of dust floating in "fountains" over the surface of the moon.

See also

* Magnetic levitation
* Optical levitation
* Acoustic levitation
* Aerodynamic levitation
* Biefeld-Brown effect
* EHD thruster
* Ionocraft ("Lifter")

External links

* [http://jnaudin.free.fr/lifters/main.htm JLN Labs: Levitators]
* [http://esl.msfc.nasa.gov/ Electrostatic levitator — Marshall Space Flight Center]
* [http://www.space.com/scienceastronomy/top_10_weird_list-7.html Electrostatic levitation raises dust particles off the surface of the moon]
* [http://www.nasatech.com/Briefs/Mar99/NPO20165.html Hybrid electric/acoustic levitation]
* [http://www.intellect.pe.u-tokyo.ac.jp/research/es_lev/es_lev_e.html Electrostatic levitation and transportation of glass or silicon plates]