Jy Portrait
Jy may refer to: *Jansky The jansky (symbol Jy, plural ''janskys'') is a non- SI unit of spectral flux density, or spectral irradiance, used especially in radio astronomy. It is equivalent to 10−26 watts per square metre per hertz. The ''flux density'' or ''mono ... (symbol Jy), non-SI unit of spectral electromagnetic flux density in radio astronomy * JY cell line, Epstein-Barr virus (EBV)-immortalised b cell lymphoblastoid line {{disambig ...
[...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  

Jansky
The jansky (symbol Jy, plural ''janskys'') is a non- SI unit of spectral flux density, or spectral irradiance, used especially in radio astronomy. It is equivalent to 10−26 watts per square metre per hertz. The ''flux density'' or ''monochromatic flux'', , of a source is the integral of the spectral radiance, , over the source solid angle: :S = \iint\limits_\text B(\theta,\phi) \,\mathrm\Omega. The unit is named after pioneering US radio astronomer Karl Guthe Jansky and is defined as :1~\mathrm = 10^~\mathrm\mathrm\mathrm ( SI) :1~\mathrm = 10^~\mathrm\mathrm\mathrm\mathrm ( cgs). Since the jansky is obtained by integrating over the whole source solid angle, it is most simply used to describe point sources; for example, the Third Cambridge Catalogue of Radio Sources (3C) reports results in janskys. * For extended sources, the surface brightness is often described with units of janskys per solid angle; for example, far-infrared (FIR) maps from the IRAS satellite are in ...
[...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]