How will the 2024 total solar eclipse differ from the 2017 solar eclipse?

(CNN) — When Mexico and North America see a total solar eclipse on April 8, it will be the first such event in this part of the world in nearly seven years, and the last time it will happen until April 8. 2044.

A total solar eclipse occurs when the Moon passes between the Earth and the Sun, completely blocking the face of the Sun. But these celestial phenomena are not all exactly the same.

While the April eclipse on August 21, 2017 has a similar path, although it moves in the opposite direction and covers more ground, there are several differences between the two that make the 2024 event a must-see. Expectations, according to NASA. A key factor that sets this year’s event apart is who will be able to see it.

NASA estimates that 215 million adults across the United States saw the 2017 eclipse directly or virtually.

“This year’s total solar eclipse will be at least partially visible to everyone in the contiguous United States, making it the most accessible eclipse this nation has experienced this generation,” said Mission Directorate Associate Administrator Nicola Fox. NASA scientists, one sentence.

A longer and more visible eclipse

More people will be able to see the 2024 eclipse because the path of totality, or the places where people will see the moon’s shadow completely cover the sun, will be wider. The Moon’s distance from Earth varies as it orbits our planet, and during the 2017 total solar eclipse, the Moon was farther from Earth and narrowed the area of ​​totality, from about 100 to 114 kilometers wide.

But the moon will be closer to our planet during this year’s event, so the path its shadow will follow over North America is expected to be 174 to 196 kilometers wide.

The path of the 2024 eclipse also passes through more densely populated areas and large cities than ever before. Only 12 million people lived within the total area of ​​the 2017 eclipse, while about 32 million people are in the path in 2024 and 150 million people live within 200 miles.

This composite image shows the progress of a partial solar eclipse over Ross Lake in North Cascades National Park in Washington on August 21, 2017. (Credit: Bill Ingalls/NAS

People outside the path of totality will still be able to see a partial solar eclipse, where the Moon blocks only part of the Sun’s face. An astonishing 99% of people living in the US, including parts of Hawaii and Alaska, will be able to glimpse at least a partial solar eclipse without having to travel.

The total duration of the April eclipse will be longer than that of 2017 due to the Moon’s closer proximity to Earth. Totality is one of the shortest phases of an eclipse and its duration depends on the viewing location. Observers near the center of the path will experience the longest totality, and that window length will decrease near the edge of the path.

In 2017, skywatchers who experienced the longest glimpse of totality were near Carbondale, Illinois for two minutes and 42 seconds.

This year, an area about 25 minutes northwest of Torren, Mexico will offer the longest totality at four minutes and 28 seconds, but people across Texas and as far north as Economy, Indiana will see totality longer than four minutes. . And when the eclipse comes to Canada, viewers can still expect to see it in totality for 3 minutes and 21 seconds.

The longest totality in recent history was seven minutes and 8 seconds and occurred on June 20, 1955, west of the Philippines, according to the Guinness Book of World Records.

Do you want to know what you will see during an eclipse? Use our interactive map to determine where you’ll be along the way. And don’t forget to bring a pair of glasses to view the eclipse safely.

The Great Solar Experiment

While eclipses are fun for sky watchers, the event also gives scientists an opportunity to study the Sun in a unique way. And the April eclipse will allow scientists to catch a glimpse of the Sun during one of its most active periods, called solar maximum.

The Sun undergoes a regular 11-year waxing and waning cycle as the star’s magnetic field changes. The 2017 eclipse occurred when the Sun was approaching solar minimum, when the star experiences the least activity.

Experts predict that solar maximum, the peak of solar magnetic field activity, will occur later this year. Scientists predict that interesting features such as bright loops, streamers and curls will appear in the Sun’s hot outer atmosphere, known as the corona, when the Moon blocks the star’s surface during the next eclipse. The corona, which is fainter than the Sun’s surface, is easier to see during an eclipse, allowing scientists to study it in more detail.

It is also possible that an explosion of material from the Sun’s surface, called a coronal mass ejection, could be seen during the eclipse.

Several experiments aboard NASA’s WB-57 high-altitude research aircraft will fly to study the corona during the eclipse, hoping to gain new details about its composition at different wavelengths of light.