surface of buoyancy
51Amphibious vehicle — An amphibious vehicle (or simply amphibian), is a vehicle or craft, that is a means of transport, viable on land as well as on water just like an amphibian.This definition applies equally to any land and water transport, small or large, powered… …
52Planetary boundary layer — Depiction of where the planetary boundary layer lies on a sunny day The planetary boundary layer (PBL), also known as the atmospheric boundary layer (ABL), is the lowest part of the atmosphere and its behavior is directly influenced by its… …
53Seabird — This article is about the animal. For the alternative rock band of the same name, see Seabird (band). The Sooty Tern is highly aerial and marine and will spend months flying at sea, returning to land only for breeding.[1] Seabirds (also known as… …
54Ventricular system — Brain: Cerebral ventricles Scheme showing relations of the ventricles to the surface of the brain …
55thunderstorm — /thun deuhr stawrm /, n. a transient storm of lightning and thunder, usually with rain and gusty winds, sometimes with hail or snow, produced by cumulonimbus clouds. Also called electrical storm. [1645 55; THUNDER + STORM] * * * Violent, short… …
56Marshall Space Flight Center — George C. Marshall Space Flight Center Aerial view of the test area at MSFC …
57Radio propagation — is a term used to explain how radio waves behave when they are transmitted, or are propagated from one point on the Earth to another. [ H. P. Westman et al, (ed), Reference Data for Radio Engineers, Fifth Edition , 1968, Howard W. Sams and Co.,… …
58Underwater diving — This article refers to underwater diving by humans. For other uses of the term diving, see dive and diving Underwater diving is the practice of going underwater with or without breathing apparatus. Recreational diving is a popular activity (also… …
59Sperm whale — Sperm Whale[1] Size compared to an average human …
60Doing It Right — DIR diver Doing It Right (DIR) is a holistic approach to scuba diving. According to the DIR approach fundamental skills, teamwork, environmental awareness, and the use of a highly optimized/streamlined (i.e. minimalistic) equipment configuration… …
