three-colour photometric system
1List of Solar System objects by size — Objects in the Solar System By orbit By size By discovery date …
2star cluster — Astron. a number of stars of common origin held together as a group by gravitational attraction. Cf. globular cluster, open cluster, stellar association. * * * ▪ astronomy Introduction either of two general types of stellar assemblages held… …
3Stellar classification — In astronomy, stellar classification is a classification of stars based on their spectral characteristics. The spectral class of a star is a designated class of a star describing the ionization of its chromosphere, what atomic excitations are… …
4Extinction (astronomy) — Extinction is a term used in astronomy to describe the absorption and scattering of electromagnetic radiation by matter (dust and gas) between an emitting astronomical object and the observer. Interstellar extinction also called Galactic… …
5photometry — photometric /foh teuh me trik/, photometrical, adj. photometrist, photometrician /foh teuh me trish euhn/, n. /foh tom i tree/, n. 1. the measurement of the intensity of light or of relative illuminating power. 2. the science dealing with such… …
6HSL and HSV — Fig. 1. HSL (a–d) and HSV (e–h). Above (a, e): cut away 3D models of each. Below: two dimensional plots showing two of a model’s three parameters at once, holding the other constant: cylindrical shells (b, f) of constant saturation, in this case… …
7star — 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,… …
8optics — /op tiks/, n. (used with a sing. v.) the branch of physical science that deals with the properties and phenomena of both visible and invisible light and with vision. [1605 15; < ML optica < Gk optiká, n. use of neut. pl. of OPTIKÓS; see OPTIC,… …
9parallax — parallactic /par euh lak tik/, adj. parallactically, adv. /par euh laks /, n. 1. the apparent displacement of an observed object due to a change in the position of the observer. 2. Astron. the apparent angular displacement of a celestial body due …
10chromatography — chromatographer, n. chromatographic /kreuh mat euh graf ik, kroh meuh teuh /, adj. chromatographically, adv. /kroh meuh tog reuh fee/, n. Chem. the separation of mixtures into their constituents by preferential adsorption by a solid, as a column… …
