A solar eclipse is coming up on Monday and for Iowans it won’t be a total eclipse.
Jefferson resident astronomy expert Drew Sorensen says Monday’s eclipse will be 83 percent covered. He tells Raccoon Valley Radio the eclipse will start around 12:45pm and last for about two hours, with the peak being at 2pm. Sorensen explains there are several different ways for people to observe an eclipse. The popular way is poking a pinhole in a paper plate and holding it above the ground to watch the eclipse safely. Sorensen talks about another way to project the eclipse using a mirror.
“It’s very much like the pinhole in the paper plate idea except you can project this farther, you can get a brighter image, and more people can see it at one time. Any mirror will work. It’s just a balance between how far you project the image and how bright or dim (it is). As you go farther away the image gets bigger but it also get dimmer.”
Sorensen notes another way is using cheap reader glasses. He says using glasses that are +1 needs a 40 inch focal length, while using +1.5 or +2 requires a shorter focal length and produces a brighter image of the eclipse. Sorensen describes the technical reason of why it’s considered to be dangerous to look directly at a solar eclipse without eye protection.
“Our sun does give off some of these other wavelengths, not just visible light. So you might not be able to see or immediately feel something, but some of those wavelengths can damage your retina and damage them permanently. So there is cause to be very careful.”
Sorensen raises caution because the weather forecast is calling for clouds on Monday, which can make watching an eclipse more difficult.