***Accommodations in southern Illinois are a hot commodity right now, filling up fast to see the August solar eclipse described below! Securing your reservations now at the Ondessonk Camp might be a good idea (It’s first come, first served), so we’re giving this blog post a very early send-out.***
There are many experiences in nature that make you go “wow!” Maybe it is your first view of the Grand Canyon, or the ocean, or even a rainbow. But what is it about an eclipse of the Sun that draws so many people? Why do some “eclipse chasers” travel thousands of miles to see an event that can, at most, last seven and a half minutes?
If you are curious, you will get your chance this August, with very little travel required. On Monday, August 21 at 11:53 a.m., the Moon will begin to cover the Sun. The Moon will be completely in front of our Sun at 1:20 p.m., and “totality” will only last two minutes and forty seconds.
However, to see this total solar eclipse, you must travel southward. You need to be in the Moon’s shadow, which begins in Oregon and travels through the Midwest, on to South Carolina. This is the first coast-to-coast eclipse in our country since 1918! It is estimated that over 12 million people will either be in the eclipse’s path (including Kansas City and St. Louis) or will travel to the path.
But what’s going on in August? Why is this happening? The Moon takes 29.5 days to orbit our Earth, which is our basis for our month, or “moonth.” During New Moon, the Moon is in the same area of the sky as our Sun, hence we only see the dark, unlit side of the Moon. The Moon’s orbit, however, is tilted five degrees to the Earth’s orbit.
To put this in perspective, if you hold out your fist at arm’s length and close one eye, one fist is about ten degrees. So a “half-fist” doesn’t seem like much, but it’s enough that the Moon usually appears to pass above or below the Sun each month. This is why we don’t have solar eclipses at every New Moon and lunar eclipses at ever Full Moon. The Moon is 400 times smaller than the Sun but it is also 400 times closer to us. Thus the Sun and the Moon appear to be the same size in our sky.
During times that the Moon does cut across the face of the Sun, the shadow of the Moon crosses the Earth, and those in the path will experience this grand event. There will be an eclipse this coming February 26 but you have to be in far southern South America or South Central Africa to see it. Which bring us to August 21.
How to View the Eclipse
If you want to see the eclipse, you must take precautions, as the Sun exhibits a blinding light. If you stay in Champaign County, 93 percent of the Sun will be covered by the Moon. While this is significant, 7 percent of the Sun will still blind you. There are several safe ways to observe the eclipse. The easiest is to locate some mylar eclipse glasses. The Staerkel Planetarium has these glasses for sale at $1 per pair. You are also safe if you have a #14 welder’s glass.
If you own a telescope, you can point the telescope at the Sun by using the telescope’s shadow. When the telescope is roughly aligned with the Sun, the shadow of the tube will look like a circle on the ground. Do NOT look through the telescope, but put a white index card roughly 6-8 inches behind the eyepiece and project an image of the Sun. Be wary of solar filters that thread into the telescope’s eyepiece! Here you are filtering the Sun at the point where the Sun’s brilliance is being focused. If the filter cracks, your eyesight is at severe risk. Appropriate solar filters attenuate the Sun’s glare before it enters the telescope.
There is also the age-old method of a pinhole camera. Hold two pieces of cardboard roughly 2-3 feet apart and put a pinhole in the sheet nearest the Sun. You should see an image of the Sun on the second sheet. Better yet, use a peg board!
Seeing the Total Eclipse: An Observing Opportunity
If you want to see the total eclipse and not a partial, you will have to head south. But where do you go? The maximum duration of this eclipse occurs near Carbondale. Good luck finding lodging in Carbondale! Any that might be available will be sold at an, shall we say, “inflated” rate. The University of Illinois Astronomy Department will set up shop in Goreville, south of Marion, Illinois.
The William M. Staerkel Planetarium is partnering with the Champaign-Urbana Astronomical Society and Twin City Amateur Astronomers (from Bloomington-Normal) to offer a weekend of observing from Camp Ondessonk (https://ondessonk.com), a Catholic youth camp located southeast of Marion and just south of Ozark, Illinois. The camp can provide rustic lodging and all meals for $115 per person. CUAS and TCAA will provide educational workshops on Sunday, the day before the eclipse, plus a dark-sky star party on Sunday night (weather permitting). Meals will be served in the camp dining hall. Tent camping is also allowed. If you would like to join us on our eclipse trek, you need to register by August 1. Point your web browser to https://ondessonk.com/event/2017-great-american-eclipse-event/ for more information. The planetarium will not be accepting registrations and there will be no event at the planetarium on the day of the eclipse.
Let’s hope for clear weather! IF we miss this event, the next “Great American Eclipse” will be on April 8, 2024!
The planetarium will be including information about the eclipse during our Friday night “Prairie Skies” star show. For more information on this event and how to observe it, go to the Staerkel Planetarium’s website and click on the image of the solar eclipse.
[Dave Leake is director of the William M. Staerkel Planetarium.]
Image from NASA.gov, with credit: Steve Albers, Boulder, CO; Dennis DiCicco, Sky and Telescope; Gary Emerson, E. E. Barnard Observatory