Circumscribed halo

{
  "id": "MLC-T-MET-004312",
  "term": "Circumscribed halo",
  "field": "Meteorology and atmospheric science",
  "definition": "A halo phenomenon that appears as an elliptical or oval-shaped ring of light that closely surrounds the sun or moon, tangent to the 22-degree halo. It forms from the refraction of light through oriented hexagonal ice crystals in cirrus clouds. The shape of the circumscribed halo changes with the elevation of the sun, becoming more circular at higher solar angles.",
  "url": "https://mlchart.com/terminology/meteorology/circumscribed-halo/"
}