emit+rays
91Black hole — For other uses, see Black hole (disambiguation). Simulated view of a black hole (center) in front of the Large Magellanic Cloud. Note the gravitat …
92Refractive index — Refraction of light at the interface between two media. In optics the refractive index or index of refraction of a substance or medium is a measure of the speed of light in that medium. It is expressed as a ratio of the speed of light in vacuum… …
93physics — /fiz iks/, n. (used with a sing. v.) the science that deals with matter, energy, motion, and force. [1580 90; see PHYSIC, ICS] * * * I Science that deals with the structure of matter and the interactions between the fundamental constituents of… …
94pulsar — /pul sahr/, n. Astron. one of several hundred known celestial objects, generally believed to be rapidly rotating neutron stars, that emit pulses of radiation, esp. radio waves, with a high degree of regularity. [1965 70; puls(ating st)ar, on the… …
95Quasar — This article is about the astronomical object. For other uses, see Quasar (disambiguation). Artist s rendering of ULAS J1120+0641, a very distant quasar powered by a black hole with a mass two billion times that of the Sun[1]. Credit: ESO/M.… …
96radiation measurement — ▪ technology Introduction technique for detecting the intensity and characteristics of ionizing radiation, such as alpha, beta, and gamma rays or neutrons, for the purpose of measurement. The term ionizing radiation refers to those… …
97Corona — This article is about the astronomical term. For other uses, see Corona (disambiguation). During a total solar eclipse, the solar corona can be seen with the naked eye. A corona is a type of plasma atmosphere of the Sun or other celestial body,… …
98Photon — This article is about the elementary particle of light. For other uses, see Photon (disambiguation). Photon Photons emitted in a coherent beam from a laser Composition Elementary particle …
99Preclinical imaging — is the visualization of animals for research purposes, such as drug development. Imaging modalities have long been crucial to the researcher in observing changes, either at the organ, tissue, cell, or molecular level, in animals responding to… …
100Cygnus X-1 — For other uses, see Cygnus X 1 (disambiguation). HDE 226868 HDE 226868 (not shown) is located next to the star η (lower center) in this map of constellation Cygnus …
