Multiple Solar Eclipses Coming Up: What is a Solar Eclipse, How to Safely Observe and Where

By Rosemary Ford and Caitlin Agnew

This article has been lightly edited for length and clarity. 

Even with the advancement of science, space has always been a fascination for many humans and this fall and spring residents of New Hampshire will get an opportunity to experience two solar eclipses. On this episode of The State We’re In, Associate Professors from University of New Hampshire , Amy Keesee and John S. Gianforte, also the director of the UNH Observatory, and Lori Harnois, Director of Division of Travel and Tourism Development discuss two important events coming up: a partial solar eclipse in October and a total solar eclipse in April. 

Melanie Plenda:

So John, let's start with you. Can you tell us a bit about what a solar eclipse is, and what happens?

John S. Gianforte:

Well a solar eclipse takes place, when the Moon comes between the Earth and the Sun, the Moon orbits the Earth about once a month, and the Earth goes around the Sun once a year. And every so often, we have an alignment that puts the Moon, the Sun and the Earth in the same plane, and the Moon casts a shadow on the Earth, if you happen to be within that shadow, actually cast to shadow so enter shadow and an outer shadow. If you happen to be in either one of them, you'll see a solar eclipse, and that's when the Moon blocks out at least a part of the Sun and blocks it from our view. And it's a really splendid site to watch if you do it safely.

Melanie Plenda:

And Amy, what makes these two eclipses one in October and one in April different?

Amy Keesee:

So the path of any Eclipse is different depending on where the shadow hits Earth. And so the path of the two eclipses is going to be different. And that's part of why we're going to observe something different. For each of the two in October, the path goes more across the western part of the United States. So in New Hampshire, we're only going to be able to observe a partial eclipse. Also, if you happen to be in the path of the October Eclipse, where there's the most coverage, it's not going to be a complete coverage of the Sun, it is going to be what's called an annular eclipse. And that means you'll still see a ring of sunlight around the Moon itself. Now in April, that's going to be a total solar eclipse. And that means that if you're in the path of totality, the Moon is going to completely block out all of the light from the Sun for a portion of it. Now you have to be in the path of totality. So that's where John was talking about the two different shadows, you have to be in the central portion of the shadow to be in the path of totality. And that's going across the northern part of New Hampshire. But all of New Hampshire is going to see a partial solar eclipse, so part of the Sun will be blocked, and you'll see sort of a crescent shape that covers it up. But we're going to see a lot more coverage in April for the partial part than you will in October for the partial part.

Melanie Plenda:

And John, what's the best way as you were mentioning to safely view these eclipses?

John S. Gianforte:

Well the two best ways to view a solar eclipse and to view the Sun at anytime doesn't have to be during an eclipse is using a projection method. A pinhole projector is probably the safest way, the easiest way. And if you are interested in doing that, all you do is take a piece of cardboard and cut a square hole in it. Cover that square hole with tin foil, pick a pinhole in that aluminum foil and then get a great big piece of poster board and on the day of the eclipse or any sunny day. Point the piece of cardboard with the pinhole and the aluminum foil up at the Sun and put the poster board behind the piece of cardboard with the pinhole in the aluminum foil and move it back and forth. And you'll see a round image of the Sun. The day of the eclipse is on October 14th which is a Saturday. A little after noon, you will see a little piece, a little nibble taken out of the Sun and won't be a complete circle. Another method that works very effectively and is very safe is to use solar eclipse glasses. And this is a great way to view the Sun anytime and especially during any partial phases of the eclipse, all through the October Eclipse. And for most of April 8 2024 Eclipse, we will be having to wear these eclipse glasses using the projection method to safely view the Sun. The only time you can observe the eclipse is if you are in the path of totality, or the Moon completely blocks the Sun. And it's only going to be for a few minutes, depending on where in the state you are, the closer to the eclipse path you are, the longer it will be totally obscured by the Moon. But that's the only time during a solar eclipse, when you can directly look at the Sun without the glasses. That's because the Moon is completely covering the disk of the Sun. And it's safe to look. But as soon as a little, little, little sprinkle of sunlight filters through the valleys and mountains on the Moon, after the eclipse is over, those glasses have to come right back on.

Melanie Plenda:

And just in case that folks at home are not yet convinced to use one of these two methods. John, what happens if you don't use these methods? Why is this necessary?

John S. Gianforte:

Well, that's a really, really good question to cover. And if you don't, the problem is it's not any more dangerous to look at the Sun during an eclipse, except you know, the eclipse is going on. So it makes you want to look. And if your eyes are unprotected, and you look at the Sun, anytime you can cause irreparable damage to the retina, the light sensitive part of your eye way at the back of your eye. It doesn't sense any pain or no pain receptors in the retina. And so you'll be burning a hole in your retina, literally, if you're looking at the Sun, without even knowing you're causing any damage. And the longer you look, the greater the damage will be. And it could very well leave you lined with really permanently visually impaired. So it's really of the utmost importance to project the image of the Sun during the partial phases. Or were the solar glasses during the partial phases.

Melanie Plenda:

So this question is for the three of you. What do you think drives our interest in eclipses? And why do you think so many people from so many walks of life find them fascinating. Let's start with Amy, then to John and Lori.

Amy Keesee:

So I think solar eclipses are a way to experience something awesome, something in science that has no barriers you're just walking around, you just need some very simple equipment to be able to observe them. And we're always fascinated by things going on in the sky, just because we experience the sky all the time. And so having something different and spectacular is very interesting to everybody. 

Melanie Plenda:

And John, what do you think?

John S. Gianforte:

Well, it's one of the few events that I can clearly say that is truly awesome. Once you see a total solar eclipse, you'll be looking online for when the next one in your area will be and they are just an awe inspiring act of nature that you can actually witness and observe without any optical aid at least the total the total part of the of the eclipse, like I mentioned, during the partial phases, you have to use the glasses or you have to project the image of the Sun. But it is absolutely an awe inspiring event for the amount of time that the Sun is completely covered by the Moon. It's just something that is completely out of our experience. And just beautiful. You will see the most beautiful shades of pink with some of these explosions of superheated plasma that you can see poking out from the black New Moon. And it's just you'll be able to see the atmosphere of the Sun called the corona. It's kind of a kind of a white light. That's coming out in many different directions from the Sun, not bright enough to hurt your eyes, but truly a spectacular sight in the daytime sky. 

Melanie Plenda:

Lori?

Lori Harnois:

Yeah, I agree with Amy and John, I think it's just a natural phenomenon that only 13 states in the United States will experience totality. And New Hampshire is one of those lucky states. And I think people want to come and see that. And from what I understand, it's when totality is happening, that you can hear noises that you typically would hear at night from the animals. So I'm really excited to, to experience it this coming spring, where

Melanie Plenda:

And John and Amy, what are you and your students planning to do around the eclipses? Let's start with John and then to Amy.

John S. Gianforte:

Well, with such a large student population and staff and faculty, we'll be having some sites on campus to view the clips from, we'll probably have telescopes equipped with solar filters, as well as some solar eclipse glasses that we've actually had one of our students designed the artwork for, and will be passing some of those out on campus. So that will be something that we're going to be doing right here in Durham, probably on the main campus where we can reach a lot of people during the eclipse, which is late in the afternoon on the 24th of April, which is a Monday. 

Melanie Plenda:

And Amy.

Amy Keesee:

Yeah, so we're also working to prepare educators across the state to work with their students in sort of the K through 12, but also informal educators, we've built a website, it's extension.unh.edu/eclipse, where we're going to have lots of resources and videos about how to prepare for the Eclipse. And we have funding from the NASA Space Grant, where we've bought some more eclipses, the ones that John was referring to get a student design, and we're going to be offering those to educators across the state so that they can plan events in their communities to observe the eclipse. We're also going to plan an open house on the UNH campus within the Physics and Astronomy Department and the Space Science Center. So probably about a week before the Eclipse people can come in, learn about the Eclipse and learn about all the awesome Sun and space related research that we do.

Melanie Plenda:

Wow, what an exciting experience that you're talking about. University of New Hampshire professors John S. Gianforte, Amy Keesee, and Lori Harnois, thank you all so much for joining us. 

The State We’re in a weekly digital public affairs show is produced by NH PBS and The Marlin Fitzwater Center for Communications. It is shared with partners in the Granite State News Collaborative, of which both organizations are members.