The one and only known home for life, Earth is one of the most interesting planets of the solar system. Life on Earth is extremely diverse; however, relative to Earth's size, all of life is contained within a very thin layer of its surface and lower atmosphere.
Another interesting fact about Earth is that its atmosphere contains high levels of molecular oxygen, making it the only breathable atmosphere in the solar system. The molecular oxygen in the atmosphere is a by-product of photosynthesis, a process by which plants and green algae transform atmospheric carbon dioxide into organic carbon with the help of sunlight as the energy source.
Earth's atmosphere protects its surface from the continuous attack of small asteroids. Most asteroids that fly towards earth fully burn out in the atmosphere and do not make an impact on the Earth's surface. The ozone layer present at the upper levels of the atmosphere protects life on Earth from the harmful ultraviolet radiation that is emitted from the sun. In addition, Earth's electromagnetic field protects the atmosphere, most importantly the ozone layer, by shielding it against the stream of charged high energy particles, otherwise known as the solar wind and cosmic rays.