The mesosphere is a layer of Earth's atmosphere located above the stratosphere and below the thermosphere, extending from about 50 to 85 kilometers (31 to 53 miles) above the Earth's surface. In this layer, temperatures decrease with altitude, reaching as low as -90 degrees Celsius (-130 degrees Fahrenheit). The mesosphere is where most meteorites burn up upon entering the atmosphere, and it is also characterized by phenomena such as noctilucent clouds and atmospheric waves. This layer is less studied than others due to its altitude and the challenges associated with direct observation.