Suggestions for Safely Enjoying the “The Great American Solar Eclipse of Aug. 21, 2017”
King University Professor Emeritus Dr. Ray Bloomer provides the informative and instructive article below to help everyone enjoy the upcoming solar eclipse on Aug. 21st.
The observation of a solar eclipse in about 1919 was the first proof that Albert Einstein's Theory of General Relativity was correct. During an eclipse scientists are able to study the outer atmosphere (corona) in terms of chemistry, density, and temperature. They can also study the magnetic fields which control so many properties of the Sun that effect the Earth.
Since the path of the Moon’s shadow across the Earth is only about 75 miles wide you must be in that path to see a total eclipse of the Sun and thus be plunged into total darkness for anywhere from 0 to 162 seconds. During that time you will be able to view the outer atmosphere or corona of the Sun with your naked eyes. (See safety suggestions below.) Outside that band you will be able to view the partially eclipsed Sun from almost anywhere in the United States (see reverse for tips.)
One of the best preparations is to download Eclipse Safari to your smart phone. It will provide details for your location (wherever that might be). (Promotions@simulationcurriculum.com) The app is available for iPhones and Android phones from their respective app stores.
NASA has a site with details on the track of the Moon’s shadow across the U.S. I like this map because it shows you most of the major roads that you can use to get to a nice place. A “nice place” is away from street lights, so I would not recommend being in a city. You need to be as close to the center line (red) as possible to enjoy the longest time of darkness. Plan on lots of traffic anywhere you go and go EARLY! https://eclipse2017.nasa.gov/sites/default/files/interactive_map/index.html
A company named Scopedawgoptics has free online maps of the entire United States along the line of longest eclipse duration: https://scopedawgoptics.com/eclipse-maps/illinois-kentucky-tennessee/.
Eye Safety: It is critical that you never look directly at even a tiny portion of the Sun’s surface called the photosphere without protection! Just a blink could result in eye damage. The appropriate glasses reduce the visible, ultraviolet and infrared radiation that can cause damage. It should have the following specification printed on it: ISO 12312-2:2015. I’m using “Eclipse Shades” by Rainbow Symphony:firstname.lastname@example.org, (818-708-6400), but I believe they may be sold out.
During a total eclipse, you can look in the direction of the Sun because you are really looking at the Moon’s near side which is not illuminated with sunlight and so it is black. When you do this you will see a dark spot where the Sun used to be and the outer layers of the Sun’s atmosphere called the corona. It is a beautiful pearly white and may show details of its structure. THE PROBLEM IS THAT UNLESS YOU ARE REALLY CAREFUL, THE SUN MIGHT POP OUT FROM BEHIND THE MOON ALLOWING YOU TO LOOK DIRECTLY AT THE SUN’S SURFACE. The best way is to put on your safety glasses during the partial phases looking now and then at the decreasingly bright Sun. Then once the eclipse is total you can take off your glasses and look at the corona. However, you must know exactly when to get everyone’s glasses back on so as not to be caught looking at the Sun with no protection. That means you must know exactly how long it will be in TOTAL eclipse and have someone in your group keep a careful track of the time! Eclipse Safari would be helpful for this problem!
You might use the following link to find the times and duration of the eclipse for your precise location. https://is.gd/2017eclipsemap. Point and click where you will be, subtract 4 hours from posted UT times, and assume the 24 military times and you will have the correct eastern daylight time, about 2:38 PM. However, if you are farther west, like I will be near Nashville, then subtract 5 hours and the time will be about 1:28 Central Daylight time. Contact me if you have a question about these times.
Observing a Partial Eclipse of the Sun
If you will not be driving to a remote location to experience a TOTAL eclipse, then the Tri-Cities is a good place to be since the Sun will be over 96% eclipsed by the Moon at one point. FOR THIS YOU WILL NEED SPECIAL EYE PROTECTION ALL THE TIME IF YOU WANT TO LOOK DIRECTLY AT THE SUN as the Moon takes a “bite” out of it. (See above for safe eye protection.)
NOTE: Do not use welding glass and other products that are not made for viewing this event.
The old tried and true method to watch a partial eclipse is to use shoe box with a 2” hole cut in one end of it. Tape a piece of aluminum foil over the hole and make a small hole in the foil using a tiny pin (thus the name pinhole camera). Hold the shoe box so it is point toward the Sun, and you should see a tiny image of the partially eclipsed Sun inside the box. Of course, you are looking AWAY from the Sun as is everyone else in your party! Check it out every 5 minutes or so.
Another very simple method is to cross the fingers on each hand with the other hand making small holes between your fingers. This will give a something similar to a “pinhole” camera effect as described above. The pinhole is then the small gaps between your fingers. Not very good images but cool looking!
Finally if you have a pair of binoculars, you might point them at the Sun, and hold a piece of paper near the eyepieces you NORMALLY look through. DO NOT LOOK THROUGH THE BINOCULAR! You are just using the binoculars to project an image of the Sun onto the paper. Mounting your binocular on a tripod makes this much easier for those of us with hands that shake a little. (I have never done this, but it should work.)
Please email about your experience! Good luck and enjoy!
King Professor Emeritus