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When a total solar eclipse creates a spectacle in the skies over Mexico and North America on April 8, it will be the first time such an event has occurred in this part of the world in almost seven years – and the last time there will be one until 2044 . . .
Total solar eclipses occur when the moon passes between the Earth and the sun, completely blocking the face of the sun. But not all these heavenly events are exactly the same.
Although the April eclipse has a path similar to that of August 21, 2017, albeit moving in the opposite direction and covering more ground, there are many differences between the two that make 2024 one to be anticipated, according to NASA. One key factor shaping this year’s event is who will be able to see it.
NASA estimates that 215 million adults across the US 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 nation’s most accessible eclipse in a generation,” said Nicola Fox, associate administrator for NASA’s Science Mission Directorate, in a statement.
A longer and more visible eclipse
More people will be able to see the 2024 eclipse because the path of totality, or locations where people will see the moon’s shadow completely covering 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 further away from Earth and caused the total area to be narrower, stretching from about 62 to 71 miles (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 stretch about 108 to 122 miles (174 to 196 kilometers) wide.
The path of the 2024 eclipse passes over areas and large cities more closely than before. Only 12 million people lived within the total area for the 2017 eclipse, and nearly 32 million are in the 2024 path, and 150 million people live within 200 miles (322 kilometers) of it.
People outside the path of totality will still be able to see a partial solar eclipse, where the moon only blocks part of the sun’s face. 99% of people living across the US, including parts of Hawaii and Alaska, will be able to view at least a partial solar eclipse without traveling.
April’s eclipse will also have a longer total period than 2017 because of the moon’s proximity to Earth. Totality is one of the shortest phases of an eclipse, and its duration depends on viewing location. Observers closest to the center of the path will have the longest total, and the length of that window decreases closer to the edge of the path.
In 2017, skygazers experienced its longest total for two minutes and 42 seconds near Carbondale, Illinois.
This year, an area about 25 minutes northwest of Torreón, Mexico, will offer the longest totality at four minutes and 28 seconds, but people across Texas and even as far north as Economy, Indiana, will see totality that last longer than four minutes. And when the eclipse crosses into Canada, viewers can still expect to see totality for 3 minutes and 21 seconds.
The longest total time in recent history was seven minutes and 8 seconds, and occurred west of the Philippines on June 20, 1955, according to the Guinness Book of World Records.
Do you want to know what you will see during the eclipse? Use our interactive map to find out where you will be on the trail. And don’t forget to take a pair of eclipse glasses to watch the event safely.
The amazing solar experiment
Although the eclipse is of interest to sky watchers, the event gives scientists the opportunity to study the sun in unique ways. And the April eclipse will give scientists a special look at the sun during one of its most active periods, known as solar maximum.
The sun has a regular 11-year cycle of waxing and waning activity associated with when the star’s magnetic field flows. The 2017 eclipse occurred as the sun approaches solar minimum, when the star has less activity.
Experts have predicted that solar maximum, the peak of the sun’s magnetic field activity, will occur later this year. Scientists expect exciting features such as loops, streams and halos to appear in the sun’s hot outer atmosphere, known as the corona, when the moon blocks the star’s surface from view during the upcoming eclipse. The corona, which is smaller than the surface of the sun, is easier to see during an eclipse, allowing scientists to study it in more detail.
It is also possible that an eruption of material from the sun’s surface, known as a coronal mass ejection, may be visible during the eclipse.
A number of experiments will fly aboard NASA’s WB-57 high-altitude research aircraft during the eclipse to study the corona in hopes of obtaining new data about its structure across different wavelengths of light.
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