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Steinberger, Jack

(Encyclopedia)Steinberger, Jack (Hans Jakob Steinberger), 1921–2020, American physicist, b. Kissingen, Germany, Ph.D. Univ. of Chicago, 1948. He and a brother were sent to the United States in 1934 as the Nazis r...

albedo

(Encyclopedia)albedo ălbēˈdō [key], reflectivity of the surface of a planet, moon, asteroid, or other celestial body that does not shine by its own light. Albedo is measured as the fraction of incident light th...

cosmic rays

(Encyclopedia)cosmic rays, charged particles moving at nearly the speed of light reaching the earth from outer space. Primary cosmic rays consist mostly of protons (nuclei of hydrogen atoms), some alpha particles (...

photoelectric effect

(Encyclopedia)photoelectric effect, emission of electrons by substances, especially metals, when light falls on their surfaces. The effect was discovered by H. R. Hertz in 1887. The failure of the classical theory ...

image

(Encyclopedia)image, in optics, likeness or counterpart of an object produced when rays of light coming from that object are reflected from a mirror or are refracted by a lens. An image of an object is also formed ...

Nakamura, Shuji

(Encyclopedia)Nakamura, Shuji, 1954–, Japanese physicist and electronics engineer, grad. Univ. of Tokushima (D.Eng., 1994). Nakamura joined the Nichia Corporation in 1977, and it was there that he began his life-...

Amano, Hiroshi

(Encyclopedia)Amano, Hiroshi, 1960–, Japanese physicist, Ph.D. Nagoya Univ., Japan, 1989. He is a professor at Nagoya Univ. in Japan. Amano is the joint recipient with Shuji Nakamura and Isamu Akasaki of the 2014...

firefly

(Encyclopedia)firefly or lightning bug, small, luminescent, carnivorous beetle of the family Lampyridae. Fireflies are well represented in temperate regions, although the majority of species are tropical and subtro...

photometry

(Encyclopedia)photometry fōtŏmˈətrē [key], branch of physics dealing with the measurement of the intensity of a source of light, such as an electric lamp, and with the intensity of light such a source may cast...

eclipse

(Encyclopedia)CE5 A. Lunar eclipse B. Solar eclipse eclipse ēklĭpsˈ, ĭ– [key] [Gr.,=failing], in astronomy, partial or total obscuring of one celestial body by the shadow of another. Best known are the lu...