A big thanks to St. Louis Science Center Planetarium educator Eric Gustafson for help answering some of these questions!
Q: What is a total solar eclipse?
A: When the moon passes between the sun and Earth, and blocks all (total) or part (partial) of the sun.
Q: What’s the big deal?
A: We haven’t had a total solar eclipse visible in St. Louis since 1442, and it won’t happen again until 2505!
Q: What is the “path of totality?”
A: This path is where the moon will completely cover the sun and the sun’s tenuous atmosphere.
Q: When is the eclipse happening in our area?
A: Monday, Aug. 21 at about 1:16 p.m. Those cities in the path of totality (DeSoto, Mo.; Chester, Mo.; Columbia, Mo.; St. Clair, Mo.) will experience a maximum of about 2 minutes and 40 seconds of darkness (as dark as about an hour after sunset), and viewers might be able to see planets and stars!
Q: Where can you buy eclipse-viewing glasses?
A: St. Louis Science Center ($2)
Places hosting eclipse events are also either giving away or selling the special glasses. CLICK HERE to see a list!
Q: Why should you wear them?
A: If you don’t wear eclipse-viewing glasses while watching the eclipse, “you will damage your eyes.”
Planetarium educator Eric Gustafson was live on KMOX 1120 last month, talking to Mark Reardon about the upcoming total solar eclipse. WATCH below!
Gustafson answered a few follow-up questions submitted by viewers:
Q: How “good” will eclipse viewing be if you are not in the “path of totality?” For example, Herculaneum, Mo. vs. Edwardsville, Ill.?
A: Herculaneum will be a good place to see the eclipse. They will get about 2 min and 32 sec of totality. The city is planning a weekend and eclipse day festival so there will be lots of stuff to do there.
Unfortunately in Edwardsville they will be outside of the path of totality. They will still see an eclipse in Edwardsville – it just will not be total. They will see a partial eclipse with about 99.47% of the Sun covered by the Moon. All the stuff they will hear about such as it getting dark, animals acting strange, the solar corona and so on will not be seen in Edwardsville. It will still be cool to see, they just won’t have any of the cool stuff seen during totality. There is definitely a distinction between in and outside of totality.
Q: What do you suggest to teachers who want their students to experience the eclipse that day? How do they keep it safe?
A: Having to work with multiple students and ensure they observe safely is an enormous concern. First thing to consider is what will be available for their school. Will they have eclipse glasses? Will they use pinhole projectors? No matter what solar viewing option they choose the advice is the same — practice. This will be difficult since most schools will have only started a few days prior.
The most important thing to discuss regarding eye damage is how the Sun damages your retinas. These are photoreceptors for your eyes, and the Sun’s light is simply too bright and it overloads your retinas with too much energy. This leads to a disease called solar retinopathy which causes vision loss. Even a quick glance can cause this damage. Once I teach them this, most students have a little more respect and reasoning for why they cannot look directly at the Sun. I then teach them the proper method to use their eclipse glasses:
1) Inspect glasses for any damage. Throw away if there are holes or scratches.
2) When outside look for a shadow. If you line up with this shadow, you are in line with the Sun.
3) Look at your feet and put glasses on.
4) Slowly look up until to find the Sun (their face changes when they find the Sun).
5) Before taking off the glasses, look back at your feet. This ensures that you are not still looking at the Sun when you take them off.
Q: How much will the weather (clouds or rain) affect eclipse viewing?
A: Simple answer is clouds are bad, but it all depends cloud type and percentage of sky cover. For instance, if they are thin, high-altitude clouds, you should still be able to see stuff through them. If they are big, billowy, cumulus or storm clouds, that is bad news. As the eclipse occurs, there will also be weather changes that occur that may break apart some of the cloud deck opening what we call sucker holes. These are breaks in clouds that sucker us to set up telescopes.
So what I would advise on eclipse day is, if there are clouds – still go out and hope for the best. Things may change throughout the day, opening gaps in clouds that will give us views. Another option is to plan for multiple viewing sites and watch the weather starting the week of the eclipse and choose which will be the best.
“It will be one of the coolest things you see in your life — get to totality,” Gustafson says.