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Jimmy Westlake’s Celestial News column appears Tuesdays in the Steamboat Today. Find more columns by Westlake here.
hursday afternoon, the moon will sideswipe the sun, creating a partial solar eclipse like the one shown in this image taken May 20, 2012. At maximum eclipse at about 4:35 p.m., 55 percent of the sun will be covered up by the moon. Warning: Never look directly at the sun without a proper solar filter, or permanent eye damage can result. The SKY Club at Colorado Mountain College will host a public “Solar Eclipse Watch” with safe solar telescopes set up for public viewing Thursday afternoon on the CMC campus.

hursday afternoon, the moon will sideswipe the sun, creating a partial solar eclipse like the one shown in this image taken May 20, 2012. At maximum eclipse at about 4:35 p.m., 55 percent of the sun will be covered up by the moon. Warning: Never look directly at the sun without a proper solar filter, or permanent eye damage can result. The SKY Club at Colorado Mountain College will host a public “Solar Eclipse Watch” with safe solar telescopes set up for public viewing Thursday afternoon on the CMC campus. Photo Courtesy Jimmy Westlake.

— The shadow of the moon will swoop across almost all of North America on Thursday when the moon crosses paths with the sun

This eclipse will not be total or annular from anywhere on Earth; it’s just a glancing blow by the moon’s shadow, creating a partial solar eclipse. Depending on where you live in Colorado, about 55 percent of the sun will be covered up by the moon.

Watching an eclipse of the sun is fun and exciting, but extreme caution must be practiced. Unfiltered sunlight can cause permanent eye damage in seconds, so never look directly at the sun, eclipse or no eclipse.

Think about it: If you focus sunlight with a magnifying lens onto a dry leaf, the leaf will get hot enough to smoke and catch on fire. Don’t forget you also have a lens in your eye, and it can focus the intense sunlight onto your retina and leave a nasty burn.

There are safe solar filters that you can purchase on the Internet, or you can use a #12 welder’s glass to view the eclipse safely.

One of my favorite ways to watch a solar eclipse is by sitting under a tree with a sheet of white poster board on the ground. The overlapping leaves — if there are any left — create hundreds of little pinholes that project images of the eclipsed sun onto the white poster board. A kitchen colander will accomplish the same thing.

Thursday’s eclipse begins at about 3:20 p.m. when the moon will take the first little “bite” out of the solar disc. Maximum eclipse is at 4:35 p.m., when about half of the sun will be covered by the moon. The eclipse ends at 5:45 p.m., about 30 minutes before the sun goes down.

Giant sunspot group 2192 is moving across the Earth-facing side of the sun this week and will make the eclipse even more interesting to watch. This active region on the sun already has unleashed one very powerful flare, and more could be in the offing.

Stay alert for the possibility of auroras in the days ahead. The NASA-sponsored website www.spaceweather.com provides aurora forecasts and warnings and is updated daily with information and images.

Student members of the Colorado Mountain College SKY Club and I will have special solar telescopes set up for safe public viewing from 3:15 to 5:45 p.m. Thursday (weather permitting). The telescopes will be outside the rear entrance of the new Academic Center on the Steamboat Springs campus.

Come on by and take a safe, close-up look at the sun and enjoy this cosmic spectacle with us. Our next solar eclipse won’t be until Aug. 21, 2017