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European Space Agency

(Encyclopedia)European Space Agency (ESA), multinational agency dedicated to the promotion, for exclusively peaceful purposes, of cooperation among European states in space research and technology. Member states in...

skin cancer

(Encyclopedia)skin cancer, malignant tumor of the skin. The most common types of skin cancer are basal cell carcinoma, squamous cell carcinoma, and melanoma. Rarer forms include mycosis fungoides (a type of lymphom...

polarization of light

(Encyclopedia)polarization of light, orientation of the vibration pattern of light waves in a singular plane. Unpolarized light can be converted into a single polarized beam by means of the Nicol prism, a device ...

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...

quantum electrodynamics

(Encyclopedia)quantum electrodynamics (QED), quantum field theory that describes the properties of electromagnetic radiation and its interaction with electrically charged matter in the framework of quantum theory. ...

space science

(Encyclopedia)space science, body of scientific knowledge as it relates to space exploration; it is sometimes also called astronautics. Space science draws on the conventional sciences of physics, chemistry, biolog...

cloud

(Encyclopedia)CE5 Approximate heights of some types of clouds cloud, aggregation of minute particles of water or ice suspended in the air. Cloudiness (or proportion of the sky covered by any form of cloud),...

atomic bomb

(Encyclopedia)atomic bomb or A-bomb, weapon deriving its explosive force from the release of nuclear energy through the fission (splitting) of heavy atomic nuclei. The first atomic bomb was produced at the Los Alam...

cosmology

(Encyclopedia)cosmology, area of science that aims at a comprehensive theory of the structure and evolution of the entire physical universe. The earliest pre-Ptolemaic theories assumed that the earth was the cent...

magnetism

(Encyclopedia)CE5 Lines of induction around a single bar magnet and between opposite poles of different magnets magnetism, force of attraction or repulsion between various substances, especially those made of i...