2017 Total Solar Eclipse Preview
Learn how you can safely see this summer's total solar eclipse! Where do you need to go? When do you need to be there? How do you protect you eyes? The time to prepare is now! Don't miss this chance to stand in the moon's shadow!
Announcer: Frostbite Theater presents... Cold Cuts! No baloney!
Joanna and Steve: Just science!
Joanna: Hi! I'm Joanna!
Steve: And I'm Steve!
Joanna: Today, we're going to answer a few questions about this summer's total solar eclipse!
Steve: The obvious first question is: What is a Solar Eclipse?
Simply put, a solar eclipse is what you get when the moon passes in front of the sun.
Joanna: If the moon only partly covers the sun, the eclipse is called a partial eclipse and the sun looks a little bit like a cookie that someone's taken a bite out of.
Steve: Sometimes, the moon passes directly in front of the sun, but it isn't large enough to cover the sun completely, kind of like trying to cover a quarter with a nickel. This kind of eclipse is called an annular eclipse and during an annular eclipse, the sun looks like a ring of light.
Joanna: A total solar eclipse occurs when the moon completely covers the sun and you're left standing in the moon's shadow.
Steve: During a total solar eclipse, the sky becomes dark during the middle of the day.
Joanna: The stars come out.
Steve: The temperature drops.
Joanna: The sun's outer atmosphere, the corona, is visible.
Steve: By all accounts, it's nothing like anything that you or I have ever seen before, and it isn't something that should be missed, if at all possible.
Which brings us to: "When is it, and where do I need to be?"
Joanna: The eclipse will take place on Monday, August 21st, 2017.
The exact 'when' depends on your exact 'where,' but your 'where' needs to be somewhere within the eclipse path.
The path stretches from Oregon to South Carolina, but it's only about 70 miles wide.
Close isn't good enough.
Make sure that you end up somewhere inside the path.
Steve: The eclipse occurs later in the day the further east you are. This is because the moon's shadow moves from west to east and because time zones exist.
If you're on the Oregon coast, totality begins around 10:15 in the morning.
If you're on the coast of South Carolina, totality begins around 2:47 in the afternoon.
You can look-up the circumstances for your specific location on-line.
Joanna: Keep in mind that totality doesn't last all that long. Remember, the moon's shadow is only about 70 miles across and it's traveling across the landscape as supersonic speeds.
The longest totality lasts is 2 minutes and 40 seconds near Carbondale, Illinois. The further you are from Carbondale, or the further you are from the center of the track, the shorter totality is.
Steve: This also means you can't afford to wait out the weather. Monitor the forecast closely and relocate if necessary.
Joanna: Okay, next question:
"Hey! Wait a second. I was told that I'll damage my eyes if I look at the sun. Won't looking at an eclipse damage my eyes?"
Yes, you can severely damage your eyes by looking at the sun. That is absolutely right. If you want to look directly at the sun, you need to use a proper filter.
Steve: There are several types of inexpensive filters available, such as these eclipse glasses. Number 14 shade welder's glass is also safe to use. But please, please, please, don't try to homebrew a filter.
Sunglasses are not safe.
Smoked glass is not safe.
There are a lot of ways to make an unsafe filter.
Please, do your eyes a favor and drop a couple of bucks on an approved filter.
Joanna: Alternatively, you can build a simple pinhole camera and view the sun's projected image. However, if you want to look directly at the sun, then you need to use a filter.
Steve: If you're going to use any optical gear, like a camera or binoculars, they need filters, too. The filters go on the front, before sunlight enters the system. And, again, this isn't the kind of thing you want to homebrew. Buy a proper filter.
Joanna: The general rule of thumb for filter use is if you can see the sun using the filter, hen you need to use a filter.
Steve: So, uneclipsed sun, I need a filter.
Joanna: Partially eclipsed sun, I need a filter.
Steve: Annular eclipse, I need a filter.
Joanna: If any part of the sun is showing, I need to use a filter.
Steve: Once totality starts, take the filters off. The moon is now your filter. A couple thousand miles worth of moon rock does a really good job of blocking sunlight.
Joanna: If you leave your filter on, you're going to miss all the exciting stuff.
Steve: This applies to cameras and binoculars, too. Filters off during totality. It's perfectly safe. Once the sun reappears, filters back on.
Joanna: Although the sun is the star of the eclipse, spend some time looking around.
Steve: Venus and Mercury should be visible, as well as some of the brighter stars.
Steve: If you have a good view of the horizon, you should notice that you're surrounded by sunset colors.
Joanna: Are animals acting differently?
Steve: Are people acting differently?
Joanna: Make your observations quickly, though. Totality will be over before you know it.
Steve: Frostbite Theater is planning an expedition out west to view the eclipse. So, if you're in the Casper area on August 21st, you might bump into us!
Joanna: Planning for this trip started nearly two years ago. If this is something that you'd like to see, you need to start planning now.
Here are some sites that can help you get started.
Steve: If you miss this eclipse, your next opportunity is on July 2, 2019, but you'll have to travel to Chile, Argentina or the South Pacific in order to see it.
The next total solar eclipse that will pass through the United States will do so on April 8th, 2024.
Joanna: Thanks for watching!
I hope that you'll join us again soon and good luck with your eclipse plans!
Steve: So, you know, this video is actually longer than totality will be.
Joanna: So many words...
Steve: Lots of words...
The following sites might be helpful in planning for the eclipse:
The 2017 total solar eclipse has come and gone and our trip to see it was a success! You can see the results here:
• 2017 Total Solar Eclipse - Third Contact Close-up
• 2017 Total Solar Eclipse - Totality Only
• 2017 Total Solar Eclipse - Complete Eclipse
• 2017 Total Solar Eclipse Preview
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For questions about this page, please contact Steve Gagnon.