radial limit
61Observational astronomy — Mayall telescope at Kitt Peak National Observatory Observational astronomy is a division of the astronomical science that is concerned with getting data, in contrast with theoretical astrophysics which is mainly concerned with finding out the… …
62North Luzon Expressway — formerly North Diversion Road Marcelo H. del Pilar Superhighway Radial Road 8 Route information Maintained by Tollways Management Corporation …
63comet — cometary /kom i ter ee/, cometic /keuh met ik/, cometical, adj. cometlike, adj. /kom it/, n. Astron. a celestial body moving about the sun, usually in a highly eccentric orbit, consisting of a central mass surrounded by an envelope of dust and… …
64river — river1 riverless, adj. riverlike, adj. /riv euhr/, n. 1. a natural stream of water of fairly large size flowing in a definite course or channel or series of diverging and converging channels. 2. a similar stream of something other than water: a… …
65Classical central-force problem — In classical mechanics, the central force problem is to determine the motion of a particle under the influence of a single central force. A central force is a force that points from the particle directly towards (or directly away from) a fixed… …
66Controlled-access highway — Freeway redirects here. For other meanings, see Freeway (disambiguation). A freeway with a wide grass median (Highway 402 in Canada) A controlled access highway is a highway designed exclusively for high speed vehicular traffic, with all traffic… …
67Brown dwarf — Brown dwarfs are sub stellar objects which are too low in mass to sustain hydrogen 1 fusion reactions in their cores, which is characteristic of stars on the main sequence. Brown dwarfs have fully convective surfaces and interiors, with no… …
68Methods of detecting extrasolar planets — Any planet is an extremely faint light source compared to its parent star. In addition to the intrinsic difficulty of detecting such a faint light source, the light from the parent star causes a glare that washes it out. For those reasons, only a …
69Particle accelerator — Atom smasher redirects here. For other uses, see Atom smasher (disambiguation). A 1960s single stage 2 MeV linear Van de Graaff accelerator, here opened for maintenance A particle accelerator[1] is a device that uses electromagnetic fields to… …
70optics — /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,… …
