What is the Brocken Spectre? A misty figure in the fog
My first Brocken Spectre. Creepy to see it out the corner of my eye and think it was someone else moving pic.twitter.com/j38PhwGZqE
— Chris Randall (@ultrapeakschris) November 13, 2022
What is the Brocken Spectre?
If you were mountain climbing, at a time of day when the sun was low and behind you, and if you climbed high enough to look down into a mist below you, you might witness the shadowy figure of the Brocken Spectre. It’s your own shadow that you see, cast on the surface of the mists below, surrounded by a halo-like ring of light. The sun must be behind you. You’re seeing your shadow projected in front of you, through the mist.
Brocken Spectres and glories
The Brocken Spectre is a type of glory. Air travelers often see glories. You have to be on the proper side of the plane, with the sun on the opposite side. Then you might see the shadow of your airplane. The airplane’s shadow will be moving along on the cloud tops, as the plane speeds through the air. A rainbow-like halo of light will surround the shadow.
You may not see the shadow of your plane either, just the rainbow halo, or glory.
If there are no clouds but you look very closely as you fly over a city opposite the sun, you might see the light reflected on windows and cars below, following your plane in a bright sparkling patch along the ground.
Brocken bow or mountain spectre
The Brocken Spectre also has the nickname Brocken bow or mountain spectre. It takes its name from the Brocken, a peak in the Harz Mountains in Germany. This region is known for frequent fogs. Johann Silberschlag, a German Lutheran theologian and natural scientist, is said to have described the Brocken Spectre in 1780. It has since figured in stories about the region and elsewhere.
At times, your shadow in a Brocken Spectre will appear enormous, but this is an optical illusion. At his great website Atmospheric Optics, Les Cowley explains why the shadow of the Brocken Spectre can appear so huge:
The spectre sometimes appears to be huge. This is probably caused by the presence of the glory and the mist obscuring more familiar reference points with which to judge its size.
Bottom line: The Brocken Spectre is your own shadow cast on mists below you, often spotted by those in the mountains. The shadow may appear enormous and has a luminous, rainbow-like ring around it.