Noctilucent clouds

{
  "id": "MLC-T-MET-001871",
  "term": "Noctilucent clouds",
  "field": "Meteorology and atmospheric science",
  "definitions": [
    "Wavy, silvery-blue clouds that form in the mesosphere, typically at altitudes between 76 and 85 kilometers, and are visible after sunset or before sunrise. These clouds are composed of tiny ice crystals that form around meteoric dust particles. Their visibility is due to the scattering of sunlight when the lower atmosphere is in darkness, making them appear to glow.",
    "Wavy, thin, bluish-white clouds that are best seen at twilight in polar latitudes. They form at altitudes about 80 to 90 km above the Earth's surface."
  ],
  "see_also": [
    "nacreous clouds",
    "Polar stratospheric clouds"
  ],
  "references": [
    "NWS Glossary"
  ],
  "url": "https://mlchart.com/terminology/meteorology/noctilucent-clouds/"
}