near-parabolic orbit
51Philosophiæ Naturalis Principia Mathematica —   Title page of Principia , first edition (1687) Original title …
52Barnaba Oriani — Born July 17, 1752(1752 07 17) Garegnano, Milan …
53Semi-minor axis — The semi minor axis of an ellipse In geometry, the semi minor axis (also semiminor axis) is a line segment associated with most conic sections (that is, with ellipses and hyperbolas). One end of the segment is the center of the conic section, and …
54List of non-periodic comets — Non periodic comets (or long period comets) are comets that do not have confirmed observations at more than one perihelion passage,[1] and thus generally have orbital periods of 200 years or more. They include single apparition comets that pass… …
55Canyon (satellite) — CANYON refers to a series of seven United States reconnaissance satellites launched between 1968 and 1977. [ [http://www.planet4589.org/space/jsr/back/news.369 Jonathan s space update No. 369] (1998 08 22) Lists U.S. SIGINT launches] Also known… …
56Aprilicus (satellite) — APRILICUS refers to a series of four United States reconnaissance satellites launched between 1978 and 1980. [ [http://www.planet4589.org/space/jsr/back/news.369 Jonathan s space update No. 369] (1998 08 22) Lists U.S. SIGINT launches] Also known …
57comet — 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… …
58telescope — /tel euh skohp /, n., adj., v., telescoped, telescoping. n. 1. an optical instrument for making distant objects appear larger and therefore nearer. One of the two principal forms (refracting telescope) consists essentially of an objective lens… …
59Weightlessness — Zero gravity redirects here. For other uses, see Zero gravity (disambiguation). Zero G redirects here. For other uses, see Zero G (disambiguation). 0G redirects here. For other uses, see 0G (disambiguation). Weightlessness (or zero g) is the… …
60Signals intelligence operational platforms by nation — This article is a subset article under the main article Signals intelligence, which addresses the unifying conceptual and technical factors and common technologies in this intelligence discipline. This article deals with current signals… …
