Joe’s blog: Rare (for us) optical phenomena seen (TUE-1/7) They come from above — not from extraterrestrials — and are a product of tiny ice crystals hanging in the atmosphere, according to ...

Cold surfaces, tiny bits of dirt, and other ice crystals are all ideal for this. On very cold days during the winter, you may see icicles hanging from yourroof. These are created by water droplets ...