Haloes and sun dogs

Mobile, Ala. — Look up, around, but not directly at the sun, and you might notice rings or arcs of color. A ring around the sun is known as a halo. Haloes form from light hitting the ice crystals of a sheet of cirrus clouds, far above the ground, and then bending or refracting at the same angle to create a circle, or just part of a circle if the clouds are patchy. Haloes show the same colors of rainbows, but they are in the opposite order. That’s one way you can tell they are not rainbows. The other way is remembering that rainbows are only seen when the sun is behind you, not in front of you.

When the sun is low in the sky, on either of both sides of the halo, you could see bright spots that show much more color. Those are nicknamed sun dogs, but the technical name is parhelia, because they are found with the sun.

There is science behind the art of the sky.

At nighttime, you’ll see a halo around the moon and that’s a lunar halo. The halo around the sun is a solar halo. These are all normal parts of meteorology that tell meteorologists what kind of clouds we have, and how the weather might change. They can be seen anywhere on Earth, in any season.

Folklore says that a ring around the moon or sun portends rain or snow within 48 hours. Folklore also says if you count the number of stars within the ring (halo) it tells you how many days before rain. Those two old sayings are not the best way to forecast weather. They have a little science behind them, but not much accuracy! Read much more about the technical side of haloes and sun dogs here.