The countdown to the total solar eclipse in April has begun. What to know about watch parties and safe viewing

The sun is about to pull another eclipse across North America, turning day into night during a total solar eclipse.

The peak of the spectacle on April 8 will last for up to 4 minutes and 28 seconds in complete darkness, twice as long as the total solar eclipse that darkened US skies in 2017.

This eclipse will take a different, more populated path, entering over the Pacific coast of Mexico, passing through Texas and Oklahoma, and crossing the Midwest, mid-Atlantic and New England, before exiting eastern Canada into the Atlantic Ocean.

An estimated 44 million people live within the 115-mile-wide (185-km) total route that runs from Mazatlán, Mexico, to Newfoundland; There are about 32 million of them in the United States, ensuring crowded roads to enjoy the must-see heavenly sensation.

Kelly Couric, NASA's eclipse program manager, said the eclipse will allow many to participate in “the wonders of the universe without going any further.”

Here's what to know about April's splendor and how to prepare for it:

What happens during a total solar eclipse?

The Moon will line up perfectly between the Earth and the Sun, blocking out the sunlight. It will take only a few hours for the moon's shadow to cut a diagonal line from southwest to northeast across North America, briefly plunging communities along the path into darkness.

Fifteen US states will get a share of this event, although two of them – Tennessee and Michigan – will barely get a share.

Among the exciting cities: Dallas; Little Rock, Arkansas; Indianapolis, Cleveland, Ohio; Buffalo, New York; and Montreal – making for the largest eclipse crowd on the continent.

Don't worry if you don't have front row seats. Virtually anyone on the continent can view at least a partial eclipse. The further we are from the path of the eclipse, the smaller the moon's bite from the sun. In Seattle and Portland, Oregon, as far away as is possible in the continental United States, a third of the sun will be swallowed.

Why is the total longer?

By a stroke of cosmic luck, the Moon will come closest to Earth during the month on the day before a total solar eclipse. This puts the Moon only 223,000 miles (360,000 km) away on the day of the eclipse.

The moon will appear slightly larger in the sky thanks to this proximity, resulting in a particularly long period of darkness obscured by the sun.

What's more, the Earth and Moon will be 93 million miles (150 million kilometers) from the Sun on that day, which is the average distance.

When the closest Moon is in conjunction with the distant Sun, the total eclipse can last an astonishing 7 1/2 minutes. The last time the world witnessed more than seven minutes of a total eclipse was in 1973 over Africa. It won't happen again until 2150 over the Pacific Ocean.

How can I watch the eclipse safely?

Sunglasses won't cut it. Special eclipse glasses are essential for safely observing the Sun as the Moon moves across the late morning and afternoon sky, covering more and more of our star.

During a total eclipse when the sun is completely covered, it's a good idea to remove your glasses and look with your naked eye. But before and after, certified eclipse glasses are essential to avoid eye damage. Just make sure it's not scratched or torn.

Cameras, binoculars and telescopes must be equipped with special solar filters for safe viewing. Bottom line: Never look into the exposed sun without proper protection any day of the year.

WHERE ARE SOME ECLIPSE VIEWING PARTIES?

Cities above and below the overall path hold star parties. Festivals, races, yoga retreats, drum circles and more will be unveiled at museums, fairgrounds, parks, stadiums, wineries, breweries and even one of Ohio's oldest movie theaters and the Indianapolis Motor Speedway.

Besides looking up, you can attend a “prom in space” in the Texas Hill Country, get married in eclipse-themed ceremonies in Tiffin, Ohio, and Russellville, Arkansas, or learn about the history of the moonwalk at the Armstrong Air and Space Museum in Wapakoneta. Ohio – the birthplace of Neil Armstrong.

As the eclipse unfolds, NASA will launch small rockets equipped with science instruments into Virginia's upper atmosphere and chase the shadow of totality from high-altitude aircraft. Satellites and the International Space Station crew will attempt to capture the display from space.

When is the next total eclipse?

A total solar eclipse occurs every one, two or three years, often in the middle of nowhere like the South Pacific or Antarctica. The next total solar eclipse, in 2026, will witness the northern edges of Greenland, Iceland and Spain.

North America won't see a total eclipse again until 2033, with Alaska getting the only dolphins. Then it will continue until 2044, when the total eclipse will be limited to western Canada, Montana and North Dakota.

There won't be another eclipse in the United States, extending from coast to coast, until 2045. This one will extend from Northern California to Cape Canaveral, Florida.

Aside from Carbondale, Illinois, which is within range of the 2017 and 2024 eclipses, it typically takes between 400 years and 1,000 years before a totality returns to the same place, according to NASA's Couric.

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