Eclipse FAQ

A total solar eclipse is an amazing phenomenon full of superlatives. Totality is a unique moment in our lives when we can experience our solar system moving in real-time motion and see the most beautiful object in the sky, the Sun's corona, which is otherwise hidden from us all our lives.

Because this is such a exceptional event, people have questions and we've got answers.

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Why is this called the Great American Eclipse?

The most common phrase used in the media to describe the coming total solar eclipse of 2017 is 'Great American Eclipse' and this is why:

  1. The 2017 eclipse will be so widely accessible to many millions of Americans because the eclipse track bisects the USA from Oregon to South Carolina. Over half the nation can reach the path of totality within one day's drive!
  2. The 2017 eclipse is the first time in 38 years that the continental USA experiences a total solar eclipse, the first time in 99 years that a total eclipse crosses from the Pacific coast to the Atlantic coast, and the first time ever that a total solar eclipse visits the USA and no other nation since the nation's founding in 1776!
  3. This is the first total solar eclipse in an industrialized country in the age of social media. Because of this, information about the eclipse will spread like wildfire and the nation will be transfixed by the extraordinary vision of eclipse day. You can be certain that this will be one of the biggest stories of summer 2017 and that you will remember this event for the rest of your life. The eclipse will truly be that impactful.
Total solar eclipse of March 9, 2016 as seen from the Makassar Strait near Indonesia

Total solar eclipse of March 9, 2016 as seen from the Makassar Strait near Indonesia

I think I saw a total solar eclipse, did I?

Probably not. If you are in doubt, you probably either saw a partial solar eclipse or a recent annular solar eclipse in 2012 or 1994. While an annular solar eclipse (when the Moon almost blocks the Sun) is interesting, it is nothing compared to the jaw-dropping sight of a total solar eclipse.

You may have seen a total solar eclipse if you lived along the US Atlantic coast in March 1970 or in the chill of February 1979 in several Pacific northwest states. Otherwise, few Americans living today have seen a total solar eclipse.

Why should I bother to drive to see the eclipse?

Simply because it is the most beautiful sight you can see in nature. Your first sight of the total phase of a solar eclipse will be unlike anything else you've ever seen. You'll be astonished at the sudden darkness in the middle of the day and it is a full sensory 

Is it safe to watch a total solar eclipse?

Yes, if you follow a couple of basic rules:

  1. When any part of the Sun's disk is visible, NEVER look directly at the Sun. You must use approved solar filters (available here) to gaze upon the partial stage of a solar eclipse. Or you can use a pinhole projection method to indirectly view the partial phase of the eclipse.
  2. If you use solar filters during the partial phase of eclipse, NEVER use these solar filters with binoculars or telescopes, unless you securely attach them on the front side of the telescope or binoculars without any gaps. Seek expert advise if you wish to do this.
  3. Only if you are inside the path of totality and when the Moon completely covers the Sun, then you can directly view the total solar eclipse during the 2 minutes of so of duration.

What time of day is a total solar eclipse? 

The total solar eclipse of August 21, 2017 has first landfall at Yaquina Head on the Oregon coast at10:15 a.m. PDT. The total solar eclipse leaves the coast of South Carolina just north of Charleston at about 2:47 p.m. EDT.

The chart on the left shows the time of greatest eclipse for every location in the U.S. If you are outside the yellow path of totality, the time is when the partial eclipse is at greatest magnitude at your location.

How long is the eclipse?

The duration of the partial phase of the solar eclipse varies by location, but it is generally between two and two and a half hours. The duration of the total phase of the solar eclipse (seen only if you are within the yellow path of totality) also varies but is longer if you are in the center of the path. If you stand precisely in the center of the path of totality, then you will experience about 2 minutes of totality which gradually increases to 2 minutes and 41 seconds in southern Illinois. So by all means, find a spot in the center of the path to get every precious second of this celestial spectacular.

Does the eclipse happen at day or night?

Believe it or not, we've been asked this question severals times. Simply put, you can only see a solar eclipses during the day and only during the New Moon. Lunar eclipses are only visible at night and during the Full Moon. Our page on eclipse basics explains this further.

The map says I can see a 90% eclipse, is that good enough?

Not even close! If you are outside the path of totality on eclipse day, you will not see the spectacle of daytime turning to deep twilight instantly, nor the stunning sight of the Sun's corona. 

Will it be cloudy?

Who knows? You'll have to wait until a few days before August 21st, 2017 to have an idea. Roughly stated, a place with very good weather statistics will experience cloudy weather about a third of the time. And a place with mediocre weather statistics will experience sunny weather about a third of the time.

So you want to stack the odds in your favor. There are two components to this: if you have the freedom to travel, target a region with superior weather odds and this is roughly from central Oregon to western Nebraska. But even if you can't easily travel to the western U.S., keep this in mind: from any place along the path of totality, if you study the weather forecast one or two days before,  

How can I get a good photo of the eclipse?

Generally, we don't recommend first time eclipse observers to attempt photography of the event. There are a couple of reasons for this: 

Unless you have specialized equipment and training, enjoy instead the amazing photographs that astrophotographers will share on social media.

You will be so astounded by the spectacle that 

Why do we have total solar eclipses?


How rare are solar eclipses?

According to retired NASA astrophysicist Fred Espenak (, a total solar eclipse is visible from any spot on Earth about once every 375 years on average. In the world, a total solar eclipse occurs on average once every 16 months or so. 

It's important to note these statistics are averages. Some lucky locations, like Carbondale, Illinois in 2017 and 2024 will enjoy two total solar eclipses with just a few years. Unlucky locations may not experience a total solar eclipse over a span of 1,000 years.

How many people live in the path of total solar eclipse?


When was the last total solar eclipse in the USA? When is the next?


How fast does the Moon's shadow travel? Can a jet keep up?


Is there a pattern to where and when solar eclipses occur?

There is a well-known pattern of eclipses called the Saros cycle.