Don’t worry. It’s totally natural. There’s no mother ship hovering above the earth, waiting to carry you away, and no demon shooting light from beneath, signaling to pull you below. It’s a light pillar — or a few of them — a colorful column of sparkling light that appears to beam up toward the sky. It’s all just an icy illusion. And now, during winter, when nights are long and cold, you have a good chance to spot one as long as conditions are right.

If you’re lucky enough to spot a light pillar, what you’re seeing is actually artificial light from a ground source reflecting off millions of floating ice crystals.

“It’s not an upward beam of light,” said Les Cowley, a physicist who runs a website on atmospheric optics, or the way light travels through the atmosphere. “Although they look pretty, they’re also a sign that someone, somewhere could do better with their lighting. You might call them light pollution pillars if you wanted to be environmental about it.”