Thermosphere

{
  "id": "MLC-T-ENV-027982",
  "term": "Thermosphere",
  "field": "Environment",
  "definition": "1. The atmospheric shell extending from the top of the mesosphere to outer space. It is a region of more or less steadily increasing temperature with height, starting at 70 or 80 km.\n\n2. Between about 53 miles (85 km) and 375 miles (600 km) lies the thermosphere. This layer is known as the upper atmosphere. While still extremely thin, the gases of the thermosphere become increasingly more dense as one descends toward the earth. As such, incoming high energy ultraviolet and x-ray radiation from the sun begins to be absorbed by the molecules in this layer and causes a large temperature increase. Because of this absorption, the temperature increases with height. From as low as -184°F (-120°C) at the bottom of this layer, temperatures can reach as high as 3,600°F (2,000°C) near the top.\n\n3. The thermosphere, from the Greek thermo for heat, begins about 80 km above the Earth. At these high altitudes, the residual atmospheric gases sort into strata according to molecular mass. Thermospheric temperatures increase with altitude due to absorption of highly energetic solar radiation by the small amount of residual oxygen still present. Temperatures can rise to 2,000 degrees C. Radiation causes the scattered air particles in this layer to become charged electrically, enabling radio waves to bounce off and be received beyond the horizon",
  "subject": "Natural environments",
  "references": [
    "NOAA National Weather Service Glossary",
    "NOAA National Weather Service JetStream - Online School for Weather at http://http://www.srh.noaa.gov/jetstream/index.htm",
    "NASA Earth Observatory Glossary"
  ],
  "url": "https://mlchart.com/terminology/environment/thermosphere/"
}