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Air Almanac
An atmosphere () is a layer of gases that envelop an astronomical object, held in place by the gravity of the object. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A stellar atmosphere is the outer region of a star, which includes the layers above the opacity (optics), opaque photosphere; stars of low temperature might have outer atmospheres containing compound molecules. The atmosphere of Earth is composed of nitrogen (78%), oxygen (21%), argon (0.9%), Carbon dioxide in Earth's atmosphere, carbon dioxide (0.04%) and trace gases. Most organisms use oxygen for respiration (physiology), respiration; lightning and bacteria perform nitrogen fixation which produces ammonia that is used to make nucleotides and amino acids; plants, algae, and cyanobacteria use carbon dioxide for photosynthesis. The layered composition of the atmosphere minimises the harmful effects of sunlight, ultraviolet radiation, solar wind, and cosmic rays ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Top Of Atmosphere
Top most commonly refers to: * Top, a basic Terms of orientation, term of orientation, distinguished from bottom, front, back, and sides * Spinning top, a ubiquitous traditional toy * Top (clothing), clothing designed to be worn over the torso * Mountain top, a mountain peak located at some distance from the nearest point of higher elevation Top may also refer to: Geography * Top, any subsidiary summit of a munro * Proper names of geographical features: ** Top River, tributary of the Olt, in Romania ** Top, Oghuz, a village in Azerbaijan ** Top, Zangilan, a village near Zangilan, Azerbaijan People * Top (surname) * Noordin Mohammad Top (1968–2009), a Malaysian/Indonesian Muslim extremist * United States military jargon for specific non-commissioned-officer ranks: ** First sergeant, Army ** Master sergeant, Marine Corps * Jargon for roles in human-sexuality: ** Top, or dominant, role in BDSM practices ** One in a triad of sexual postural preferences, specifically Top, bottom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
