Image linked to original source; Image description: A double rainbow in Alaska

    Figure: A rainbow in Alaska, a full circle rainbow, and a glory

    Image 1 Caption: "Full featured double rainbow in Wrangell-St. Elias National Park and Preserve, Alaska."

    Click on image and the next image version for the high-resolution version.

    Image linked to original source; Image description: A full circle rainbow, but not all of it is in the image Further explication:

    1. The solar axis runs through the photographer whose shadow is seen at the center bottom. The 2 cones of light rays forming the primary rainbow and secondary rainbow have their apex at the photographer. The fiducial mean opening angle of the primary rainbow cone is 42°; that of the secondary rainbow is 52° (see Wikipedia: Rainbow: Double rainbow).

    2. Image 2 Caption: A full circle rainbow, but it is not all in the image.

      One needs to be high up with water drops everywhere below, but above the ground, of course, to see a full circle rainbow. You can see full-circle rainbows from very tall buildings and airplanes, but they are NOT commonly seen it seems.

      Full circle rainbows are NOT the same as glories. See Image 3 below.

      Image linked to original source; Image description: A glory seen over Canada

    3. Image 3 Caption: A glory seen over Canada.

      An atmospheric effect that is similar in appearance to a rainbow, but has a smaller angular diameter measured from the solar optical axis is the glory. They are NOT caused by the rainbow mechanism: they are caused by a combination of refraction AND interference effects in water droplets.

      People often see full circle glories from airplanes. Yours truly probably saw a glory once from an airplane.

    Images:
    1. Credit/Permission: © Eric Rolph, before or circa 2007 (uploaded to Wikimedia Commons by User:BokicaK, 2007) / Creative Commons CC BY-SA 2.5.
      Image link: Wikimedia Commons: File:Double-alaskan-rainbow.jpg.
    2. Credit/Permission: Jakob Owens, 2017 (uploaded to Wikimedia Commons by User:Fæ, 2017) / Public domain.
      Image link: Wikimedia Commons: File:Full Rainbow (Unsplash).jpg.
    3. Credit/Permission: © Brocken Inaglory, 2005 (uploaded to Wikimedia Commons by User:Mbz1, 2007) / CC BY-SA 3.0.
      Image link: Wikimedia Commons: File:IMG 7474 solar glory.JPG.
    Local file: local link: rainbow_alaska.html.
    File: Electromagnetic Radiation file: rainbow_alaska.html.