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Sky-gazers Across North America is in for a treat on April 8, when a total solar eclipse will sweep across Mexico, the United States and Canada.
The event will be visible to millions of people – including 32 million people in the US alone – who live along the path the moon’s shadow will take during the eclipse, known as the path of totality. For those in the areas experiencing totality, the moon’s shadow will completely cover the sun. Those along the center line of the path will see a solar eclipse lasting between 3½ and 4 minutes, according to NASA.
The next total solar eclipse won’t be visible again in the contiguous United States until August 2044. (It’s been more than six years since the “Great American Eclipse” of 2017.) And no annular solar eclipse will appear in this part of the United States. the world again until 2046.
Here’s everything you need to know about the upcoming solar eclipse.
What is a total solar eclipse?
A total solar eclipse occurs when the moon passes between the Earth and the sun, completely blocking the face of the sun.
Those within the path of totality, or locations where the moon’s shadow will completely cover the sun, will see a total solar eclipse. People outside the path of totality will still be able to see a partial solar eclipse, in which the moon blocks only part of the sun’s face.
During a total solar eclipse, the sky will darken, just like at sunrise or sunset, and there are different stages of the eclipse that skygazers can anticipate.
The moon does not suddenly appear between the earth and the sun; the event begins with a partial solar eclipse where the moon appears to take a “bite” out of the sun, making the sun look like a crescent moon. Depending on your location, the partial solar eclipse could last between 70 and 80 minutes, according to NASA.
When the moon begins to cross in front of the sun, the star’s rays will shine around valleys on the moon’s horizon, creating glowing droplets of light around the moon in a phenomenon called Baily’s beads.
As totality approaches, Baily’s beads will quickly disappear until a single point of light remains, resembling a glittering giant diamond ring.
The diamond ring will disappear when totality arrives and there is no longer any sign of direct sunlight. Bright stars or planets may shine in the dark sky, and the air temperature will drop as the sun disappears. The sudden darkness causes animals to become silent.
The chromosphere, or part of the Sun’s atmosphere, may glow in a thin pink circle around the Moon during totality, while the Sun’s hot outer atmosphere, or corona, will appear as white light.
As the moon continues its journey across the face of the sun, Baily’s diamond ring and beads and the partial solar eclipse will appear on the far side of the moon until the sun rises. appears completely again.
Where can I see the solar eclipse?
The total solar eclipse will be visible in parts of Mexico, Canada and more than ten US states, while a crescentic partial eclipse is expected to occur in 49 states – weather permitting.
The eclipse will first appear over the South Pacific and then begin its journey across North America. Mexico’s Pacific coast is the first point of totality on the path, expected at 11:07 a.m. PT (2:07 p.m. ET).
The trail continues through Texas, Oklahoma, Arkansas, Missouri, Illinois, Kentucky, Indiana, Ohio, Pennsylvania, New York, Vermont, New Hampshire and Maine. The route then crosses Canada through southern Ontario, Quebec, New Brunswick, Prince Edward Island and Nova Scotia, ending on the Atlantic coast of Newfoundland at 5:16 PM (3:46 PM ET).
Use our interactive map to determine what the eclipse will look like from your viewing location.
How can I watch the solar eclipse safely?
The only time it is safe to look at the sun without eye protection is during the “totality” of a total solar eclipse, or the brief moments when the moon completely blocks the sun’s light and no sunlight is visible, according to NASA .
Otherwise, wear certified eclipse glasses that comply with ISO 12312-2 or use a portable solar binocular before and after totality, and at all times during a partial solar eclipse.
In addition, you can observe the sun with a telescope, binoculars or camera with a special solar filter on the front, which works in the same way as eclipse glasses.
Staring directly at the sun can lead to blindness or impaired vision. During the 2017 total solar eclipse, a young woman was diagnosed with solar retinopathy, damage to the retina due to exposure to solar radiation, in both eyes after viewing the eclipse with what doctors thought were eclipse glasses that were not on the safety standard met. There is no treatment for solar retinopathy. It may improve or worsen, but it is a permanent condition.
Sunglasses do not take the place of eclipse glasses or solar binoculars, which are 100,000 times darker and meet an international safety standard.
The lenses of solar eclipse glasses are made of black polymer, or resin, infused with carbon particles, which block almost all visible, infrared and ultraviolet light, according to The Planetary Society. Sunglasses do not block infrared radiation.
For safe manufacturers and resellers of eclipse glasses and filters for optical devices, including cameras and smartphones, check out the list compiled by the American Astronomical Society.
Put on your eclipse glasses before looking up and remember to turn away from the sun before taking them off. Always supervise children wearing eclipse glasses to ensure they do not remove them while looking at the sun.
If you normally wear glasses, keep them on and place eclipse glasses over them or hold a portable viewer in front of them, according to the American Astronomical Society.
Don’t look at the sun through an unfiltered optical device — camera lens, telescope, binoculars — while wearing eclipse glasses or using handheld solar binoculars, according to NASA.
The sun’s rays can still burn through the filter of glasses or binoculars, given how concentrated they can be through an optical device, and can cause serious eye damage.
If you purchased eclipse glasses to view the “ring of fire,” store your eclipse glasses and binoculars for the April total solar eclipse by storing them at room temperature in an envelope or in the original packaging to prevent scratches.
What can we learn from eclipses?
Eclipses provide scientists with the opportunity to study the sun and how it interacts with Earth in unique ways, and NASA has selected several projects to fund during the total solar eclipse.
“Scientists have long used solar eclipses to make scientific discoveries,” Kelly Korreck, program scientist at NASA, said in a statement. “They helped us make the first detection of helium, gave us evidence for general relativity and allowed us to better understand the sun’s influence on Earth’s upper atmosphere.”
One project will rely on NASA’s high-altitude research aircraft to capture images of the eclipse from 50,000 feet (15,240 meters) above Earth’s surface to capture previously invisible details in the Sun’s corona. The images could also help scientists search for asteroids orbiting near the sun.
Amateur radio operators will conduct an experiment during both the annular and total solar eclipses to see how these phenomena change the way radio waves propagate. Operators at different locations record the strength of their signals and how far they travel. Scientists are interested in tracking this distance because the sun directly affects the Earth’s upper atmosphere, the ionosphere, allowing radio communications to travel further. But if the moon blocks the sun, that can change.
Scientists and citizen scientists alike plan to observe the most active regions of the sun as the moon passes over them during both eclipses using the Goldstone Apple Valley Radio Telescope.
The sun is currently approaching solar maximum later this year, and scientists are keen to capture this peak of activity through a variety of observations that can only take place during eclipses.
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