luminosity
91X-ray astronomy — X rays start at 0.008 nm and extend across the electromagnetic spectrum to 8 nm, over which the Earth s atmosphere is opaque. X ray astronomy is an observational branch of astronomy which deals with the study of X ray observation and detection… …
92Barn (unit) — A barn (symbol b) is a unit of area. Originally used in nuclear physics for expressing the cross sectional area of nuclei and nuclear reactions, today it is used in all fields of high energy physics to express the cross sections of any scattering …
93Andromeda Galaxy — The Andromeda Galax …
94Lux — For other uses, see Lux (disambiguation). A lux meter for measuring illuminances in work places. The lux (symbol: lx) is the SI unit of illuminance and luminous emittance measuring luminous power per area. It is used in photometry as a measure of …
95Small Magellanic Cloud — Small Magellanic Cloud. Source: Digitized Sky Survey 2 Observation data (J2000 epoch) …
96Standard candle — A standard candle is an astronomical object that has a known luminosity. Standard candles are the basis for several important methods of deriving distances in extragalactic astronomy and cosmology in the cosmic distance ladder.TheoryComparing its …
97Radio galaxy — Radio galaxies and their relatives, radio loud quasars and blazars, are types of active galaxy that are very luminous at radio wavelengths (up to 1038 W between 10 MHz and 100 GHz). The radio emission is due to the synchrotron process. The… …
98Daisyworld — Plots from a standard black white DaisyWorld simulation. Daisyworld, a computer simulation, is a hypothetical world orbiting a star whose radiant energy is slowly increasing. It is meant to mimic important elements of the Earth Sun system, and… …
99Blazar — A blazar is a very compact and highly variable energy source associated with a presumed supermassive black hole at the center of a host galaxy. Blazars are among the most violent phenomena in the universe and are an important topic in… …
100Stellar structure — Stars of different mass and age have varying internal structures. Stellar structure models describe the internal structure of a star in detail and make detailed predictions about the luminosity, the color and the future evolution of the… …
