General Eclipse Information

On April 8, 2024, a total solar eclipse will cross the continental United States, providing an exciting and breathtaking opportunity for observation and science. A total solar eclipse happens when the Moon passes between the Sun and Earth, completely blocking the face of the Sun. People located in the center of the Moon’s shadow when it hits Earth will experience a total eclipse.

The sky will darken, as if it were dawn or dusk. Weather permitting, people in the path of a total solar eclipse can see the Sun’s corona, or outer atmosphere, which is usually obscured by the bright face of the Sun. This total solar eclipse will be visible in 15 U.S. states, and a partial solar eclipse will be visible in all 49 continental states.

Observing our star, the Sun, can be safe and inspirational. The only safe way to look directly at the uneclipsed or partially eclipsed Sun is with specialized eye protection, such as eclipse glasses, a solar viewer, or through a telescope with a solar filter. You can also use an indirect viewing method, such as a pinhole projector. During the brief totality phase of the total solar eclipse in April 2024, you can enjoy the solar corona without eclipse glasses.

You can safely view the Sun any day, even when there isn’t an eclipse, as long as you use specialized eye protection, such as eclipse glasses, a solar viewer, or a telescope with a solar filter. You can also use an indirect viewing method, such as a pinhole projector.

Eclipses are a unique opportunity to participate in a celestial event, and experiencing an eclipse is one way that everyone can participate in NASA Science. You can work together with NASA to make discoveries possible before, during, and after an eclipse, and you do not have to be in the eclipse path to participate.

Partial? Annular? Total?

While partial and annular eclipses are more common, a total solar eclipse is once in a lifetime. This is due to the distance between the Sun, Moon and Earth along with their elliptical orbits.

Almost everyone has heard of a total solar eclipse — also known as a total eclipse of the Sun — but it's often mixed up with a 'ring of fire' annular solar eclipse ("annular" means "ring"). Both types of solar eclipses are described by astronomers as central solar eclipses, but the exact geometrical differences between them are slight. However, those differences have a huge effect on what observers see, feel and experience. While one of the eclipse types can be described merely as a beautiful sight the other is an awe-inspiring multi-sensory experience. 

The basic reason solar eclipses happen is because the Moon orbits Earth every 27 days, so often gets roughly between the Earth and the Sun. However, solar eclipses do not happen every month. That's because the plane of the Moon's orbit of Earth is tilted by 5º with respect to Earth's orbit of the sun. Twice each month the Moon crosses the aptly-named ecliptic — the path of the Sun through our daytime sky — at points that astronomers called nodes, according to EarthSky. If a new Moon crosses the ecliptic it causes a solar eclipse, which it can do during every year's two eclipse seasons. 

It's possible for the Moon to block the Sun because on average it's 400 times smaller than the Sun, but also 400 times closer to Earth. The two objects thus have a very similar apparent size in our sky. It's an incredible coincidence, but in reality, it doesn't quite work out like that. Something else happens that results in two different kinds of solar eclipses.

Source: Great American Eclipse


The 15 lucky states that will be visited by the Moon’s shadow during the total solar eclipse are Texas, Arkansas, Oklahoma, Missouri, Tennessee, Illinois, Kentucky, Indiana, Ohio, Michigan, Pennsylvania, New York, Vermont, New Hampshire, and Maine. Tennessee and Michigan are omitted because the Moon’s shadow only touches a small corner of these two states.

Anticipation for the April 8, 2024 total solar eclipse will be sky high! Not only are there 32 million people already living within the USA section of the path, but metropolitan areas such as St Louis, Cincinnati, Detroit, Toronto, and Quebec are very close to the path. The major cities of Boston, New York, Philadelphia, Baltimore, and Washington, D.C., are all within 200 miles of the path of totality.  So be prepared for the single-biggest mass travel event in the USA.