Watch out — on Aug. 21, the heavens will align and the moon will darken the sun in what’s being called the Great American Eclipse. According to space.com, total solar eclipses happen approximately every 18 months, but they vary widely in when they're visible from some point on Earth's surface — in fact, according to NASA, this is the first time that a total solar eclipse will be visible in the United States since 1991, and it won't happen again until 2024.
But what exactly is a total solar eclipse?
“An eclipse is a general term for when one object goes in between another object and the solar system, so like three objects lining up,” said Darin Ragozzine, an assistant professor in the physics and astronomy department at Brigham Young University. “And in particular, the solar eclipse is when the moon goes in front of the sun from our perspective.”
“The moon orbits Earth, Earth orbits the sun, and they’re sort of in the same plane but not entirely,” added Joseph Moody, also a professor in the physics and astronomy department at BYU. “ The moon’s going to go around in the sky relative to the sun once every month, and when it comes close to the sun, it usually goes a little bit above it or a little bit below it. But every now and then, it’s going to go right in front of it, and when that happens, it just blocks its light, casting a shadow onto Earth’s surface, and that shadow falls on various places. Turns out on Aug. 21, that shadow’s going to cut right across North America.”
Moody said that traditionally, eclipses were a chance for scientists to learn more about the atmosphere of the sun, but today’s instruments allow them to do that without an eclipse; however, “the main thing about the eclipse is that it’s an amazing public outreach tool,” Ragozzine said, “and we’re using it to help people understand more about our solar system and where we live.”
With that in mind, here’s everything you need to know to experience this extraordinary celestial event.
The times and places
According to greatamericaneclipse.com, the eclipse will cut diagonally across North America between Oregon and South Carolina, with totality (the eclipse phase in which the moon completely blocks the sun) lasting anywhere from 1 minute 17 seconds to 2 minutes 41.6 seconds at different times and places. For Utahns, the closest places to view totality will be the Snake River Valley, Idaho, area at 11:33 a.m. MDT for 2 minutes 18 seconds, and the Casper, Wyoming, area at 11:42 a.m. MDT for 2 minutes 26 seconds.
For a full list of times and places to view totality, visit greatamericaneclipse.com.
The hotels and campsites
According to an article from the Rexburg Standard Journal, all Upper Valley hotels are booked, as well Eagle Park, Beaver Dick Park and Twin Bridges Park.
However, a number of Airbnb rentals are available, and Brigham Young University-Idaho has approved owners of university owned housing to rent out their buildings for the eclipse. For more information and to stay updated, check Rexburg's eclipse website.
In Wyoming, the city of Casper is hosting the 2017 Wyoming Eclipse Festival. Its website includes an extensive travel page, which lists a number of camping and hotel accommodations, and the page is regularly updated to include only places that still have availability.
Ragozzine, however, said that people don't necessarily have to travel to see the eclipse because a thin crescent of the sun will be visible virtually everywhere in the United States. He also said that in northern Utah, about 90 percent of the sun will be covered around 11:35 a.m.
The glasses and gear
“The most important thing for people to know is that it is not safe to look even at a small part of the sun without special glasses,” Ragozzine said. “Not sunglasses — special sun viewing glasses that are made for that purpose.”
This means that at every eclipse phase except totality, viewers need eclipse glasses. According to NASA, four manufacturers are certified to the international standard for making them: Rainbow Symphony, American Paper Optics, Thousand Oaks Optical and TSE 17. The only time it's safe to look directly at the eclipse without these glasses is during totality.
Other things that eclipse viewers might use to make the most of their experience include cameras, telescopes and binoculars, though it's never safe to look directly at the sun or a partial eclipse through these devices without a solar filter. It is also not safe to look through unfiltered optical devices even while wearing eclipse glasses.
In addition, eclipse glasses are available for $1 through BYU. Call Denise Stephens at 801-422-2167 to order and arrange pickup on campus, or order through newfrontiergames.com (free shipping for over 10 pairs of glasses, otherwise there's a flat shipping rate of $3). Profits will go towards the BYU Astronomical Society's free public astronomy day. Supplies are limited.
For Raggozine, the Great American Eclipse is an almost once-in-a-lifetime opportunity.
"I like to say (it's a) twice-in-a-lifetime (opportunity) to be within driving distance of a total solar eclipse," he said. " It’s a rare opportunity and fun."
Moody agreed that this is a special event.
"This one is unusual, very unusual, in that it’s cutting right through a populated area," he said "Frankly, if you don’t go, you’re not going to have anything to talk about with anybody else for a month."