More brilliant than the sun or any other natural light source visible on earth is the man-made fireball of the atomic and hydrogen detonations. Depending on the intensity, light sources of such extreme brightness may have both temporary glare and burning effects. The glare effects from nuclear explosions are similar to those experienced when looking directly at the sun. The permanent lesions from the fireballs have a parallel in the chorioretinal burns described as eclipse blindness.* For generations smoked glass has been used to prevent eclipse burns. Very dense filters f have been routinely and successfully employed to protect the eyes of observers of experimental atomic detonations.
On a theoretical basis2 it had been predicted that damage to the unprotected retina would occur at distances greater than any known biological effect from the fireball of atomic detonations. To test this prediction, extensive experiments with rabbits have been performed and
ROSE HW, BROWN DVL, BYRNES VA, CIBIS PA. Human Chorioretinal Burns from Atomic Fireballs. AMA Arch Ophthalmol. 1956;55(2):205-210. doi:10.1001/archopht.1956.00930030207006