On Monday, August 21, much of the mainland United States will experience something that hasn’t happened in over 38 years: a total eclipse of the Sun. The last time such an event the mainland US was February 1979. A total of 14 states will experience totality on August 21, but much of the rest of the country will still experience a partial eclipse of the sun that day as well.
In case you are unfamiliar with how a solar eclipse occurs, it happens when the silhouette of the Earth’s moon covers the sun completely for a small period of time. This results in generating a darkness in the middle of the day, but also allows people to view the Sun’s corona, which looks like a band of light stretching out from the dark circle created by the eclipse.
Needless to say, such an astronomical event has been highly anticipated in the US for quite some time. If you are in the path of the total eclipse shadow, or even if you will only get to see a partial eclipse of the Sun, there are ways to view the event safely.
When, where and for how long?
As we stated, the total eclipse of the Sun will occur on Monday, August 21. The 70 mile wide path of totality will be visible in parts of Oregon, Idaho, Wyoming, Montana, Iowa, Kansas, Nebraska, Missouri, Illinois, Kentucky, Tennessee, Georgia, North Carolina, and South Carolina. It will officially begin at 1:16 Eastern time on Oregon’s coast, and the shadow will move through the other states very quickly, ending at 2:48 pm ET in Charleston, SC.
It’s estimated that about 12.2 million people live where the path of the total eclipse will happen, while another 88 million live within a day’s drive of the shadow. That means a ton of people will be able to experience the event. The actual total eclipse time will vary, depending on the shadow’s path and location, but the longest period of totality will be 2 minutes, 41.6 seconds, inside the Giant City State Park in Illinois.
How to view the partial eclipse safely
Before totality happens, the shadow of the Moon will create a partial eclipse of the Sun, and will do so again after the totality event is over. In addition, all of North America will get to experience a partial eclipse of the sun on August 21, along with Western Europe, the northern part of South America, and some locations in Africa and Asia.
During the time of the partial eclipse, it is extremely important that people not look directly at the Sun without some form of protection for their eyes, even if the Sun is 99 percent covered by the Moon’s shadow, The Sun’s photospheric crescent is still visible during that time, and its rays could cause permanent damage to the naked eye.
The partial eclipse can be viewed with special protective glasses. Regular sunglasses are not enough; you will need to get your hands on glasses that have a thin layer of aluminum, chromium or silver that can filter out the dangerous light generated from a partial eclipse. They should also be both ISO and CE certified. Such glasses, along with specially made binoculars, are available for sale on Amazon. You might also be able to get one during an eclipse viewing party.
The safest way to view a partial eclipse is by not looking at it directly at all. Instead, you can see an image of the partial eclipse via a pinhole that can project an image of the sun to a surface about 1.5 feet or more beyond that pinhole. There are a number of ways to create a simple, and cheap, pinhole box to safely view the partial eclipse.
If you are in the path of totality, you can view the Sun with the naked eye during that brief amount of time, and see the corona of the Sun coming out of the Moon’s shadow. This is the only part of the event where you will be able to do this, so be sure to look away, or view the Sun with filtered glasses, once the total eclipse part of the event is over.
Of course, you want to make sure that you can experience the total eclipse for as long as you can. We’ve already mentioned where the longest period of totality will happen in the US, but other locations in the US will have long eclipse periods as well.
Viewing any total eclipse of the Sun can be a truly awe-inspiring event, and since the mainland US has waited so long for such an eclipse to occur over the country, it’s become one of the most anticipated days of 2017. However, no one wants to have that astronomical event to be tarnished by damaged eyes, so be sure to view it safely.
By the way, the US won’t have to wait quite as long for the next total eclipse; another will occur over the mainland US in April 2024. An annular solar eclipse, where the Moon’s shadow crosses over the Sun but is too small to cover it completely, will happen over part of the US even earlier, in October 2023.