Tesla (unit) Tesla (unit) The tesla (symbol T) is a derived unit of the magnetic field strength (also, magnetic flux density) in the International System of Units. One tesla is equal to one weber per square metre. The unit was announced during the General Conference on Weights and Measures in 1960 and is named in honour of Nikola Tesla, upon the proposal of the Slovenian electrical engineer France Avčin. The strongest fields encountered from permanent magnets are from Halbach spheres and can be over 4.5 T. The record for the highest sustained pulsed magnetic field has been produced by scientists at the
Spectral flux density the investigator is interested only in a specific direction, for example the vertical direction referred to a point in a planetary or stellar atmosphere, because the atmosphere there is considered to be the same in every horizontal direction, so that only the vertical component of the flux is of interest. Then the horizontal components of flux are considered to cancel each other by symmetry, leaving only the vertical component of the flux as non-zero. In this case some astrophysicists think in terms of the astrophysical flux (density), which they define as the vertical component of the flux (of the above