Don’t you hate those moments when you wished you had a camera, but you didn’t. Yeah, well had one of those moments recently, when I witnessed a phenomenon that I’d never seen before. It was pretty amazing, but I didn’t have a friggin camera, so you’ll just have to believe me. I was high on a mountain side above lake Wakatipu, near Glenorchy. We were hoping to get a decent view from the top, but we were climbing through cloud for most of the way. It wasn’t looking likely that we were going to break through the top of the clouds. It’s a bit demoralising, when you’re busting your backside to get to the top of a mountain, and all you get to see at the top is this:
But the clouds started to clear, and like a ray from heaven, the sun broke through. The tip of the mountain we were standing on was suddenly a small island amongst a sea of clouds, and I witnessed a holy revelation. (Well, that’s how people have historically interpreted this phenomenon).
With the sun behind me, my shadow was being magnified to make me a giant, and was being cast onto the clouds below me. Surrounding my body was a perfect, circular rainbow. It was like there was a holy halo surrounding my body.
I found out later, that what I saw was called a Brocken Spectre. It is named after Brocken, the highest peak in Germany’s Harz Mountains, where it has often been witnessed. In reality, the magnification of the shadow is an optical illusion, but because the sun is casting your shadow onto the clouds at an oblique angle, it makes you look like a giant. Also, the shadow is generally on clouds that are nearby, but you are comparing it to far-away objects, such as the tips of other mountains, so it looks huge. The shadow appears to move, which adds to the freakiness of the whole phenomenon, but it is just the clouds moving.
The rainbow is known as a Glory, and radiates out from the head of the shadow. There is still debate amongst physicists as to how the glory actually happens, but is thought to be due to classic wave tunnelling. This means the light is cast through air inside each water droplet, and is refracted backwards. From the perspective of the person making the shadow, a full rainbow is visible.
This phenomenon has been referenced countless times in literature and songs, and has often been interpreted as a sign from God, or as ‘Buddha’s light’. I prefer to appreciate the fact that it is a phenomenon that only a few lucky people get to witness, through being in the right place at the right time.