
Upper Atmosphere
Upper atmosphere is a collective term that refers to various layers of the atmosphere of the Earth above the troposphere and corresponding regions of the atmospheres of other planets, and includes: • The mesosphere, which on Earth lies between the altitudes of about 50 and 80 kilometres, sometimes considered part of the "middle atmosphere" rather than the upper atmosphere • The thermosphere, which on Earth lies between the altitudes of about 80 and 700 kilometres • The exosphere, which on Earth lies between the altitudes of about 700 kilometres and 10,000 kilometres • The ionosphere, an ionized portion of the upper atmosphere which includes the upper mesosphere, thermosphere, and lower exosphere and on Earth lies between the altitudes of 48 and 965 kilometres.