Altitude is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The exact definition and reference datum varies according to the context
An airliner flying in the stratosphere where airliners typically cruise to reduce fuel consumption. The blue layer is the ozone layer, fading further to the mesosphere.
The atmosphere of Earth consists of a layer of mixed gas that is retained by gravity, surrounding the Earth's surface. It contains variable quantities of suspended aerosols and particulates that creat
Altitude
…Density altitude – the density of the air in terms of altitude in the International Standard Atmosphere in the air The Earth's atmosphere is divided into several altitude regions. These regions start and finish at varying heights depending on season and distance from the poles. The altitudes…
Earth's atmosphere from space, showing a blue layer at the stratosphere, above the clouds of the troposphere. The Moon is visible as a crescent in the background.
Afterglow of the troposphere (orange), the stratosphere (blue) and the mesosphere (dark) at which atmospheric entry begins, leaving smoke trails, such as in this case of a spacecraft reentry
In 1960, Joseph Kittinger set a record by parachuting from a gondola at 31.3 km (19.4 mi)
Earth from orbit, showing sunlight filtered into a reddish hue by the troposphere, while casting shadows from different cloud types. The stratosphere forms a thin band of blue scattered sunlight along the horizon.