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profile of the Earth’s atmosphereclick to hear

Atmosphere: layer of air that surrounds the Earth and is composed mainly of nitrogen (78%) and oxygen (21%); its density decreases with altitude.
profile of the Earth’s atmosphere space probe artificial satellite space shuttle aurora shooting star airliner ozone layer Mt Everest supersonic jet cloud sea level troposphere stratosphere tropopause stratopause mesosphere mesopause thermosphere thermopause exosphere temperature scale altitude scale Hubble space telescope

space probe click to hear

Unmanned craft launched in the direction of a celestial body in the solar system for purposes of studying it.

artificial satellite click to hear

Observation spacecraft placed in orbit around the Earth.

space shuttle click to hear

It orbits at an altitude of about 250 mi.

aurora click to hear

Luminous phenomenon that occurs at high altitudes near the Earth’s poles.

shooting star click to hear

Luminous trace produced when a meteorite burns up as it enters the Earth’s atmosphere.

airliner click to hear

Commercial aircraft that makes regular flights of variable duration, depending on the distance covered; it flies at altitudes of 39,000 feet.

ozone layer click to hear

Layer of gas that absorbs a large part of the Sun’s ultraviolet rays.

Mt Everest click to hear

The world’s highest peak rises to an elevation of 29,035 feet.

supersonic jet click to hear

Aircraft whose cruising speed is faster than the speed of sound; it flies at altitudes of 62,000 feet.

cloud click to hear

Fine droplets of water or ice crystals suspended in the atmosphere.

sea level click to hear

Average height of seawater observed for a given time (day, month, year); it is used as a reference point to define coastal features and measure land elevations.

troposphere click to hear

The most dense layer, which produces most of the meteorological phenomena and where temperatures decrease with altitude.

stratosphere click to hear

Highly stable layer of air where temperatures increase with altitude due to the absorption of solar radiation by the ozone layer.

tropopause click to hear

The boundary between the troposphere and the stratosphere; its altitude varies depending on the season, ground temperature, latitude and atmospheric pressure.

stratopause click to hear

Thin transition layer between the stratosphere and the mesosphere.

mesosphere click to hear

The atmosphere’s coldest layer, where temperatures decrease with altitude.

mesopause click to hear

Thin transition layer between the mesosphere and the thermosphere.

thermosphere click to hear

Layer that absorbs a large portion of solar radiation, leading to a steady increase in its temperature.

thermopause click to hear

Thin transition layer between the thermosphere and the exosphere.

exosphere click to hear

The outermost region of the atmosphere, where low-density gases disperse into space.

temperature scale click to hear

altitude scale click to hear

Hubble space telescope click to hear

Telescope placed in orbit above Earth’s atmosphere (370 mi), making it possible to observe the universe as never before.