Recently, near Phoenix, Ariz., there was a huge gray circle, outlined in soft gold, around the sun. We were wondering what this signifies and what caused the broad ring. Thank you for this information.

What you saw was a solar halo. Halos are produced when light from the sun or the moon strikes ice crystals suspended at altitudes above 25,000 feet. Such ice crystals are present in a rather thin veil of cirrostratus clouds. The practical value of halos for a weather forecast is that the cobweb-like cirrostratus clouds usually precede a warm front and the accompanying precipitation. Actually, a halo in winter doesn’t have that absolute significance; however, during the warmer months, a halo usually foretells the coming of a thickening cloud ceiling of warm moist air. In most cases, a long, slow rain could arrive in about 12 to 18 hours.

But to accurately predict precipitation depends chiefly on your location; the closer you are to a normal storm track, the more likely a halo will predict rain. Also, precipitation tends to develop more quickly with a halo that appears in winter as opposed to summer.

The precise size of a halo is due to the shape of ice crystals. Light enters one side of a six-sided crystal and is refracted (bent) because light travels more slowly through ice than through air. As light leaves the crystal through another side, it is refracted again. Light is usually bent at an angle of 22 degrees, creating the most commonly observed halo. Halos seldom have much color; they are commonly soft white circles in the sky. But sometimes, especially with solar halos, they can appear like vivid rainbows, with a dull red inside and a bluish white outside.

(Of course, if you attempt to observe a ring or halo around the sun, make sure you protect your eyes and don’t risk blinding yourself.)

There’s another halo, sometimes called a great halo, which is not seen very often. It appears at an angle of 46 degrees from the sun or moon and forms by the same principle as the normal 22-degree halo. In a great halo, light can enter the top of the crystal and emerge from a side, or can enter a side and pass out the bottom.

To see both a regular halo and a great halo, the sun or moon must be shining through two layers of cirrostratus clouds. At low sun angles, if the ice crystals in the clouds are just right, one may see arcs, sun pillars and other curious effects. When other circlets form on the circumference of a primary halo, they are known as mock suns or sundogs.

I got candle wax on my carpet. Do you have any suggestions on how to get it off?

To get the wax off easily, use a piece of wax paper or freezer paper and an iron. Heat the iron on a low to medium setting.

Place the paper on top of the wax on the carpet and then iron. The heat from the iron will melt the wax onto the paper and remove it from your carpet.

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