We sat down with Professor Bruce Palmquist, who teaches both physics and astronomy at Central Washington University, to learn more about the upcoming solar eclipse. Palmquist reported, "There are two types of eclipses, lunar and solar. Both happen two times a year. They aren't always total, and they aren't always over the same space."
He used an example that the moon is orbiting around the edge of a plate. The Earth is at the center of that plate. That plate is tipped compared to the angle of the plate that has the Earth orbiting the sun. The Earth plate "wobbles," which takes about 19 years to go all the way up and back down, which is why the eclipses aren't in the same places every year. Because of the variation, there are also eclipse "seasons" which change slightly year to year, about half a month. That means sometimes there could be three eclipses in a year.
The total eclipses are rare. The band of the total eclipse is only 100 miles wide maximally, but this year it will be about 70 miles. The band doesn't always go east to west, it can also go north-south. This year the band is only going to be visible in the United States, which is why it's being called "The Great American Eclipse." The last solar eclipse was over the Pacific Ocean, visible to a little bit of Indonesia.
The only safe time to look directly at the sun is during total part of the eclipse. That's still a bad idea, because even if 99.9% of the sun is blocked, the 0.1% is powerful enough to damage your eyes. The sun's energy will harm the cones and rods in your eye. This will burn them out and create a blind spot, similar to the blind-spot created by the optic nerve. Also, don't look at the sun directly, even through binoculars or a telescope.
There are a couple ways to safely watch the eclipse. There are eclipse glasses available online. It's very important to get high quality ones. There are vendors selling fake glasses, and unfortunately online sellers are jacking up prices as the eclipse draws near. They will block out all the light necessary to watch, regular sunglasses aren't good enough. A welder's mask with number 14 glass works.
Another option is to do a simple craft project to use a shoe box or milk carton to view the eclipse. There are also instructions for using binoculars or a telescope and cardboard. https://www.timeanddate.com/eclipse/box-pinhole-projector.html
Granite Falls is north of the total eclipse band, but will still experience an 86% eclipse. Palmquist said it will be similar to a cloudy day. The eclipse will start at around 11:40 a.m. Central Time. The peak will be a little after 1:00 p.m. and will last about 2 minutes. Palmquist recommends looking at the sun multiple times during the event. Minute to minute changes will be hard to detect, but, for example, 15 min or so there should be a visible difference.
As for taking pictures, he says that it is tough without a fancy camera. "A lot of people will be taking pictures, but it's your responsibility to actually watch the eclipse."