Atmosphere - online puzzles

Atmosphere

An atmosphere (from Ancient Greek ἀτμός (atmós) 'vapour, steam', and σφαῖρα (sphaîra) 'sphere') is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. 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 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 (0.04 %) and trace gases. Most organisms use oxygen for respiration; lightning and bacteria perform nitrogen fixation to produce 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 to protect organisms from genetic damage. The current composition of the atmosphere of the Earth is the product of billions of years of biochemical modification of the paleoatmosphere by living organisms.

one piece ship online puzzleRainbow, thunderstorm and lightning online puzzlegray asphalt road under white clouds and blue sky online puzzlegreen pine trees near body of water during daytime sliding puzzle onlinethe sucker online puzzlegreen trees on mountain during daytime sliding puzzle onlineamazing photo in orange online puzzlegreen trees under gray clouds online puzzle4x10KMRelay sliding puzzle onlinegreen and brown trees near mountain during daytime sliding puzzle onlinecity buildings under blue sky during daytime online puzzleThrone <Tyrell. sliding puzzle onlineDarrell's Amazing Race sliding puzzle onlinesnow covered mountain under cloudy sky during daytime online puzzlesponge bop sliding puzzle onlineSnow,landscape,twilight online puzzlegreen trees on mountain during daytime online puzzleStars above Zihuatanejo sliding puzzle onlineSunrise sliding puzzle onlinesilhouette of lighthouse on beach during sunset sliding puzzle onlineTeam Comp sliding puzzle onlineSpace with X-ORG sliding puzzle onlinegreen grass field near mountain under blue sky sliding puzzle onlineScream the movie online puzzleThe grave of Christ online puzzlePurple sky sliding puzzle onlineMission to Mars online puzzlebody of water during sunset sliding puzzle onlinebrown concrete building near body of water during night time online puzzlelandscape - perfect morning sliding puzzle onlineThe man flies to heaven online puzzleMan and the Universe online puzzleAmsterdam street online puzzlecity near body of water during sunset sliding puzzle onlineAutumn 0987 sliding puzzle onlineLet's wander in the forest... sliding puzzle onlinegreen trees on brown mountain during daytime sliding puzzle onlineocean waves crashing on shore during daytime online puzzleJINKI HYUNG sliding puzzle onlinewinter evening - sunset online puzzlesnow covered mountain under blue sky during daytime sliding puzzle onlineaerial view of green grass field during daytime sliding puzzle onlineThe challenge flams and fire sliding puzzle onlineEasy Slide online puzzlegreen pine trees on mountain during daytime online puzzlesilhouette of people on beach during sunset online puzzlebody of water under blue sky during daytime online puzzlegreen trees under blue sky during daytime online puzzle