standard: SHA-1 described at URL: https://svs.gsfc.nasa.gov/5366 URL: https://svs.gsfc.nasa.gov/vis/a000000/a005300/a005366/pinhole_valleys_2160p30.mp4...
English Valleys around the lunar limb act like pinholes projecting images of the Sun onto the surface of the Earth during the August 21, 2017 total solar eclipse...