On April 8, 2024, millions of people across Central and North America will be treated to a spectacular total solar eclipse. The celestial event comes seven years after the "Great American Eclipse" of August 21, 2017 — the first total solar eclipse visible from coast to coast since June 8, 1918. For those who miss the April 2024 show, the next chance to see the spectacle will be August 12, 2045.
What causes a solar eclipse?
A solar eclipse occurs when the Moon passes between the Sun and the Earth, casting its shadow on Earth. However, we do not experience a total solar eclipse every time this happens. That is because the Moon's elliptical orbit causes its distance from Earth to vary between 221,500 and 252,000 miles (about 356,000 and 406,000 km). For a total eclipse to occur, the Moon must be at its closest orbital distance (so it appears larger than the Sun) and perfectly aligned with the Earth and the Sun. On April 8, 2024, the Moon will be just 223,000 miles (about 360,000 km) from Earth.
Are total solar eclipses rare?
Total solar eclipses occur about every 18 months. But they are only visible to those directly in the path of the Moon's umbra. This is the darkest part of the shadow where the Sun's entire surface is covered. The narrow "path of totality" is typically between 93 and 155 miles (150 and 250 km) wide. As a result, only a small percentage of people worldwide can enjoy the experience live. Moreover, total solar eclipses occur at a specific location about every 360 years. So, seeing one in real-time is usually a once-in-a-lifetime opportunity.
Who will be able to see the April 8 eclipse?
All of North and Central America will be able to see a partial eclipse. However, the total eclipse will only be visible to the approximately 31 million people who live within the 115-mile (185-km) path of totality.
The natural phenomenon will start on Mexico's Pacific coast at about 11:07 a.m. PDT on April 8. In the US, the residents of Eagle Pass, Texas, will be the first to experience total darkness at 11:27 a.m. PDT. Over the next hour and a half, the eclipse will traverse the rest of Texas, Oklahoma, Arkansas, Missouri, Illinois, Kentucky, Indiana, Ohio, Pennsylvania, New York, Vermont, New Hampshire, and Maine. Parts of Tennessee and Michigan will also be able to see the total eclipse.
Mexico and Texas will witness the maximum totality of about 4 minutes and 28 seconds. After that point, the Moon's shadow will start to lengthen and narrow. By the time the eclipse exits North America, the Moon will cover the Sun's disk for just 2 minutes and 52 seconds.
Those in the path of the total eclipse will experience a surreal darkness creeping towards and over them as the Moon positions itself perfectly between the Sun and the Earth. Once the Sun's disk is completely covered, they will witness a breathtaking sight of its corona, or outer atmosphere. Bright stars and planets will also be visible in the middle of the day. The total eclipse will last just a few minutes. But partial eclipses will continue for over an hour as the Moon moves in and out of our star's path.
How to view the solar eclipse
Unlike lunar eclipses, solar eclipses must be observed through special glasses. The ultraviolet radiation from the Sun can lead to permanent eye damage or blindness. If protective eye coverings are not available, a simple, homemade pinhole camera — which projects the Sun's disk onto paper or another surface — can also be used.
Happy viewing!
Resources: NASA.gov, Space.com, Nationaleclipse.com, CNN.com
