What is an Eclips and Where Will You See It
Where will you be next Monday morning around 10:15? With any luck, you will be able to watch the solar eclipse that will cover most of North America. A solar eclipse occurs when the moon passes between the sun and Earth and blocks all or part of the sun. The process takes up to three hours, from beginning to end, when viewed from a given location.
For this eclipse, the longest period when the moon will completely block the sun from any given location along the path will be about two minutes and 40 seconds. The last time the contiguous U.S. saw a total eclipse was in 1979.
According to NASA, an estimated 500 million people will be able to observe the August 21, 2017 total solar eclipse, in partial or total form: 391 million in the U.S., 35 million in Canada, and 119 million in Mexico (plus Central America and parts of South America and northwestern Europe).
To see a total eclipse, where the moon fully covers the sun for a short few minutes, you must be in the path of totality. The path of totality is a relatively thin ribbon, around 70 miles wide, that will cross the U.S. from West to East. We’ve heard lots of people are making plans to travel to location where they will be able to see the full effects.
According to NASA, the first point of contact in the U.S. will be at Lincoln Beach, Oregon at 9:05 a.m. PDT. Totality begins there at 10:16 a.m. PDT. Over the next hour and a half, totality will cross through Oregon, Idaho, Wyoming, Montana, Nebraska, Iowa, Kansas, Missouri, Illinois, Kentucky, Tennessee, Georgia, and North and South Carolina. The totality will end near Charleston, South Carolina at 2:48 p.m. EDT. From there, the lunar shadow leaves the United States at 4:09 EDT. Its longest duration will be near Carbondale, Illinois, where the sun will be completely covered for two minutes and 40 seconds.
It’s estimated that here in Los Angeles, we will only see about 60-70% of the sun blocked by the moon. We found this movie, made by the University of California at Berkeley, that will approximate what you will see from any given location (just type in your zip code).
Safely Viewing an Eclipse
The only safe way to look directly at the uneclipsed or partially eclipsed sun is through special-purpose solar filters, such as eclipse glasses or handheld solar viewers. Homemade filters or ordinary sunglasses, even very dark ones (unless they’re #14 welding glasses), are not safe for looking at the sun. In the 70-mile-wide swath of the country that will experience a total eclipse, it’s safe to look at the total eclipse with your naked eyes only during the brief period of totality, which will last about two minutes, depending on your location.
There’s been a lot of confusion about the safety of some glasses since Amazon issued a recall notice. We got some eclipse glasses From Landis Labyrinth toys for $1.95 each. We checked with Landis staff, who said they bought them from a “reputable source,” and consider them to be safe. The American Astronomical Society offers a list of reputable suppliers as one sure way to know your glasses are up to current safety standards. Also, see this link for other ways to tell if your glasses might be safe – in short:
“You shouldn’t be able to see anything through a safe solar filter except the sun itself or something comparably bright, such as the sun reflected in a mirror, a sunglint off shiny metal, the hot filament of an unfrosted incandescent light bulb, a bright halogen light bulb, a multiple-white-LED flashlight, or an arc-welder’s torch.”
If you want avoid direct viewing, consider making a pinhole projector. With this method, sunlight streams through a small hole – such as a pencil hole in a piece of paper, or even the space between your fingers – onto a makeshift screen, such as a piece of paper or the ground. It’s important to watch the screen, not the sun. There are lots of ways you can create a pinhole project, including using a common kitchen colander (which projects dozens of images at one time).
Or, you can get online and see images captured in space. Thanks to NASA, viewers around the world will be provided a wealth of images captured before, during, and after the eclipse by 11 spacecraft, at least three NASA aircraft, more than 50 high-altitude balloons, and the astronauts aboard the International Space Station – each offering a unique vantage point for the celestial event.
There are also lots of events around the city planned for viewing the eclipse. Local libraries, including Memorial Branch and Washington Irving Branch are planning viewing events; some will have glasses available but not all. Here’s a complete list of LA Libraries organizing events.
The California Science Center is planning a Solar Eclipse Festival on the weekend before the eclipse, and will have an expert from JPL available to answer questions on Monday during the eclipse. The Science Center will have safe viewing tools available, too.
Finally, Griffith Observatory is also hosting a big eclipse viewing event…but we’re guessing that one’s going to be very popular and crowded. Check their link, though – it has lots of other useful information, including a list of other big viewing events.
There’s so much more eclipse information out there than we have included, but you have a week to get ready – so have fun planning and viewing!