QUIET SUN: The sun is peppered with 'spots today, but none pose a threat for strong flares. Solar activity should remain low.

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HAPPY BIRTHDAY, GALILEO: On February 15, 1564, Galileo Galilei was born in Pisa, Italy. If he were alive today he would be 441 years old. Galileo is an important person in the history of space weather. Contrary to popular belief, he didn't discover sunspots, but he was one of the first to observe them using a telescope.

In Galileo's day, many people believed sunspots were satellites of the sun. Galileo proved otherwise. By drawing sunspots every day, he discovered that the sun spins and that sunspots are located on (or very near) the sun's surface. Galileo thought sunspots might be clouds.

Right: Sunspots drawn by Galileo in June 1612. [more drawings]

Now we know what sunspots really are: magnetic islands. Sunspots consist of magnetic force-fields poking through the sun's surface from below. Sometimes these magnetic fields erupt, producing a solar flare. With a temperature of "only" a few thousand degrees C, sunspots are cooler than their surroundings and, thus, they appear dark. Sunspots are as big as planets.

Above: A 7-day movie of the Sun captured Feb. 8th - 15th by the Solar and Heliospheric Observatory (SOHO).

There are plenty of 'spots on the sun today, and you can observe them the same way Galileo did, by projecting an image of the sun onto a white screen. Try it!

MOONDOGS: Sometimes, when the moon is bright and icy cirrus clouds are criss-crossing the sky, you can see something beautiful: moondogs, rainbow-colored splashes of light that appear to the left and right of the moon. These moondogs appeared over North Carolina on Jan. 27th:

"Our club, the Cleveland County Astronomical Society, had just finished meeting when a few members noticed a bright rainbow patch in the sky," says photographer Brett Clapper. "We stepped back and were surprised to see two moondogs!"

When you see a moondog, it means that the clouds overhead are full of plate-shaped ice crystals. These plates drift slowly downwards like leaves with their large faces almost horizontal. Each plate acts like a tiny prism, transforming ordinary moonbeams into 'dogs. Moondogs are often accompanied by moon halos. Watch for them, too!