Thursday, May 28, 2020


Heiligenschein, is an optical effect where a bright spot appears to surround the cast shadow of the head of the observer. The glowing spot is caused by rays of sunlight reflecting back from individual dewdrops, and the effect is best seen on a cool, clear morning.

The word translates from the German as "saintly illumination" or "holy light." The effect was described in the memoirs of Benvenuto Cellini (1500-1571), so it's sometimes called "Cellini's halo."
Photo courtesy New York Times, which published the article "How to become an angel in the morning dew"
Heiligenschein on Wikipedia


Roberto Quintana said...

This is fascinating! Where is the 'halo' refraction taking place? Around the head, and being projected onto the ground by the sun? (possibly from increased moisture from a warm breath in the cool air is my guess.)
or is the halo actually around the shadow (created by angels in the mist?)
Also, can the halo be seen by others, from different angles as the subject moves? or seen just by the person casting the shadow? Best -RQ

James Gurney said...

Roberto, it's a virtual glow around the antisolar point from the POV of the observer, and it can only be seen by the person casting the shadow. The reflection takes place inside the tiny spherical droplets of dew. Light goes in one side and comes back in the same direction.

Jim Williams said...

Went out this morning and saw it around my head on the grass. Thanks for telling me about this!

Roberto Quintana said...

Thanx, James.
So it's not 'Angels in the Mist' but rather 'Angles in the Dew'.
;) -RQ

Carly said...

Why is it around the head? Because that's where our eyes are to see it?