Here’s what to know about next week’s total solar eclipse 

Parts of North America will be dark next week because of a rare celestial phenomenon that will not return for the next few decades.

A total solar eclipse is set to take place next Monday, for the first time since 2017, completely blocking off the mask of the sun. 

What a total solar eclipse is

“A total solar eclipse happens when the Moon passes between the Sun and Earth, completely blocking the face of the Sun,” according to NASA. 

The eclipse will last longer than the one in 2017 because the moon will be closer to Earth than usual — 223,000 miles apart at that time. The totality of the eclipse will be the longest over Mexico at 4 minutes and 28 seconds, according to NASA. In Syracuse, N.Y., the eclipse will only last 1 1/2 minutes. 

When it will happen

A total solar eclipse will take place April 8. The last one occurred in August 2017. It will be a few decades until another occurs. 

The next total solar eclipse is slated for August 2044 in Montana and North Dakota, per NASA.

The path of the eclipse 

The path of the eclipse will bring the moon’s shadow over communities from the Southwest U.S. to the Northeast, with 15 states expected to experience the total eclipse. 

The eclipse will travel from Texas and pass through Oklahoma, Arkansas, Missouri, Illinois, Kentucky, Indiana, Ohio, Pennsylvania, New York, Vermont, New Hampshire and Maine, according to NASA. 

How people can watch it safely

NASA is offering a livestream. 

Looking at the sun during the eclipse can cause “eclipse blindness.” Regular sunglasses will not offer adequate protection. 

The glasses people should use have a filter called ISO 12312-2. 

“Unfortunately, sunglasses are not enough, because you need them to actually be 1,000 times darker than regular sunglasses,” an ophthalmologist and assistant professor at the Cleveland Clinic Cole Eye Institute, Dr. Nicole Bajic, told ABC News. “So, we are looking specifically for the eclipse glasses, and these have a special filter called the ISO 12312-2.”

Eclipse glasses should be on during the parietal solar eclipse. 

A special-purpose solar filter should be on if watching through a telescope or a camera lens, according to NASA. 

It is safe to remove the glasses during the short period of totality, when the moon completely covers the sun. When the moon moves on, glasses should be back on.