The Air Up There Trivia Quiz

The troposphere is the lowest layer of Earth's atmosphere. It contains about 75% of the atmosphere's mass and most of its water vapor. Weather phenomena, like clouds, rain, and storms, occur within the troposphere. This layer also holds objects such as airplanes during most commercial flights, birds, and human-built structures like weather balloons.

The tropopause is the boundary layer between the troposphere (the lowest part of Earth's atmosphere, where weather occurs) and the stratosphere (the layer above). It acts as a barrier, preventing most clouds and weather systems from rising into the stratosphere.

The height of the tropopause varies depending on location and season, ranging from about 8 kilometers (5 miles) near the poles to around 18 kilometers (11 miles) near the equator.

The stratosphere is the second layer of Earth's atmosphere, sitting above the troposphere. The ozone layer can be found within this layer. Unlike the troposphere, the temperature in the stratosphere increases with altitude due to the absorption of radiation by ozone. Objects that can be found in this layer include high-altitude weather balloons, some types of research aircraft, and certain long-range military jets.

The stratopause is the boundary layer between the stratosphere and the mesosphere. It marks the top of the stratosphere and is characterized by a temperature maximum, where the warming effect from the ozone layer in the stratosphere ends. The stratopause is located at an altitude of about 50 kilometers (31 miles) above the Earth's surface.

The mesosphere is the third layer of Earth's atmosphere, located above the stratosphere. Here, temperature decreases with altitude, making it the coldest layer of the atmosphere. The mesosphere is where most meteors burn up upon entering the Earth's atmosphere, producing the bright streaks we sometimes call shooting stars. Because of its thin air and extremely low temperatures, this layer is not suitable for conventional aircraft or weather balloons.

The mesopause is the boundary layer between the mesosphere and the thermosphere. It is known for being the coldest region of the atmosphere, with temperatures dropping to as low as -90°C (-130°F). The mesopause is located at an altitude of around 85 kilometers (53 miles) above the Earth's surface.

The thermosphere is the fourth layer of Earth's atmosphere. Temperatures in the thermosphere can get extremely high, reaching thousands of degrees Celsius, due to the absorption of intense solar radiation. The thermosphere is where the auroras, or northern and southern lights, occur, and it is also the region where the International Space Station (ISS) and some satellites orbit.

The thermopause is the boundary layer at the top of the thermosphere, marking the transition between Earth's atmosphere and the exosphere. It is the point where the atmosphere becomes so thin that it no longer behaves like a fluid, and the effects of solar radiation become extremely significant.

The altitude of the thermopause varies greatly, depending on solar activity, but it typically ranges from about 500 to 1,000 kilometers (310 to 620 miles) above the Earth's surface.

The exosphere is the outermost layer of Earth's atmosphere, gradually fading into the vacuum of outer space. In this layer, air density is extremely low, and gas molecules are so sparse that they can travel hundreds of kilometers without colliding with one another. Because of this, the exosphere does not behave like the lower atmospheric layers. Satellites in high orbits, such as those used for GPS, geostationary communications, and some scientific observations, operate in this region.

External space refers to the vast expanse beyond Earth's atmosphere, where the atmosphere becomes almost non-existent and space conditions dominate. This region is characterized by a near vacuum, with extremely low densities of particles, no breathable air, and a lack of atmospheric pressure. Objects sent into external space are mostly limited to space probes and rockets meant to explore other parts of the Solar System; long-range, infrared space telescopes; and various bits of debris from previous space missions.