Abundance of the chemical elements — Estimated proportions of matter, dark matter and dark energy in the universe. Only the fraction of the mass and energy in the universe labeled atoms is composed of chemical elements. The abundance of a chemical element measures how relatively… … Wikipedia
Measurement of biodiversity — Main article: Biodiversity Polar bears on the sea ice of the Arctic Ocean, near the north pole. A variety of objective measures have been created in order to empirically measure biodiversity. Each measure of biodiversity relates to a particular… … Wikipedia
Big Bang nucleosynthesis — In physical cosmology, Big Bang nucleosynthesis (or primordial nucleosynthesis) refers to the production of nuclei other than those of H 1 (i.e. the normal, light isotope of hydrogen, whose nuclei consist of a single proton each) during the early … Wikipedia
dating — I In geology and archaeology, the process of determining an object s or event s place within a chronological scheme. Scientists may use either relative dating, in which items are sequenced on the basis of stratigraphic clues (see stratigraphy) or … Universalium
cosmos — /koz meuhs, mohs/, n., pl. cosmos, cosmoses for 2, 4. 1. the world or universe regarded as an orderly, harmonious system. 2. a complete, orderly, harmonious system. 3. order; harmony. 4. any composite plant of the genus Cosmos, of tropical… … Universalium
Life Sciences — ▪ 2009 Introduction Zoology In 2008 several zoological studies provided new insights into how species life history traits (such as the timing of reproduction or the length of life of adult individuals) are derived in part as responses to… … Universalium
General relativity — For a generally accessible and less technical introduction to the topic, see Introduction to general relativity. General relativity Introduction Mathematical formulation Resources … Wikipedia
mass spectrometry — or mass spectroscopy Analytic technique by which chemical substances are identified by sorting gaseous ions by mass using electric and magnetic fields. A mass spectrometer uses electrical means to detect the sorted ions, while a mass spectrograph … Universalium
star — starless, adj. /stahr/, n., adj., v., starred, starring. n. 1. any of the heavenly bodies, except the moon, appearing as fixed luminous points in the sky at night. 2. Astron. any of the large, self luminous, heavenly bodies, as the sun, Polaris,… … Universalium
Earth Sciences — ▪ 2009 Introduction Geology and Geochemistry The theme of the 33rd International Geological Congress, which was held in Norway in August 2008, was “Earth System Science: Foundation for Sustainable Development.” It was attended by nearly… … Universalium
Cosmic ray — For the film, see Cosmic Ray (film). Cosmic radiation redirects here. For some background types of cosmic radiation, see cosmic background radiation and cosmic background. The energy spectrum for cosmic rays Cosmic rays are energetic charged… … Wikipedia