The mesosphere contains different kinds of gases that are mixed in the air and a deep sodium layer. Most meteors from space burn up in this layer. A special type of clouds, called noctilucent clouds, sometimes forms near the North and South Poles of the mesosphere, and there are also strong zonal (east-west) winds, atmospheric tides, internal atmospheric gravity waves and planetary waves.
The mesosphere is the layer of the Earth's atmosphere that is directly above the stratopause and directly below the mesopause. The mesosphere starts at 50 km (31 miles) above the Earth's surface and goes up to 85 km (53 miles) high. In the mesosphere, temperature decreases with increasing height. The coldest temperatures in Earth's atmosphere, about minus 90 degrees C (minus 130 degrees F), are found near the top of this layer.
Scientists know less about the mesosphere than about other layers of the atmosphere. Weather balloons and jet planes cannot fly high enough to reach the mesosphere, and the orbits of satellites, on the other hand, are above the mesosphere. It has only been accessed using sounding rockets. Sounding rockets make short flights that don't go into orbit. The presence of electrical discharges or lightning within the lower mesosphere, called red sprites and blue jets, noctilucent clouds and density shears within the poorly understood layer are of current scientific interest.