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Those who look at the sky A total solar eclipse will occur across North America on April 8 over Mexico, the United States, and Canada.
The event will be visible to millions of people, including 32 million people in the United States alone, who live along the path the moon’s shadow will travel during the eclipse, known as the path of totality. For those in areas experiencing totality, the moon’s shadow will completely cover the sun. According to NASA, those along the middle line of the path will see an eclipse that will last 3½ to 4 minutes.
The next total solar eclipse will not be visible from the contiguous United States again until August 2044. (It’s been more than six years since the “Great American Eclipse” of 2017.) And an annular eclipse will not be visible on this part of Earth. The world again by 2046.
Here’s everything you need to know about the upcoming eclipse.
What is a total solar eclipse?
A total solar eclipse occurs when the Moon comes between the Earth and the Sun, completely blocking the Sun’s face.
Those on the path of totality or places where the moon’s shadow will completely block the sun will see a total solar eclipse. People outside the path of totality will still be able to see a partial solar eclipse, where the moon covers only part of the sun’s face.
During a total solar eclipse, the sky will darken as at dawn or dusk, and there are several phases of the eclipse that skygazers can predict.
The moon does not suddenly appear between the Earth and the sun; The event begins with a partial eclipse that causes the moon to take a “bite” from the sun, causing the sun to resemble a crescent. Depending on your location, the partial eclipse could last between 70 and 80 minutes, according to NASA.
As the moon begins to pass in front of the sun, the star’s rays will shine around valleys on the moon’s horizon, creating bright blobs of light around the moon in a phenomenon called Baily beads.
As totality approaches, Baily’s beads will rapidly disappear until only a single point of light remains, resembling a shiny giant diamond ring.
When totality comes, the diamond ring will disappear and there will no longer be any signs of direct sunlight. Bright stars or planets may shine in the dark sky, and the air temperature will drop when the sun disappears. Sudden darkness causes animals to become quiet.
The chromosphere, or part of the sun’s atmosphere, may shine as a thin pink circle around the moon during totality, while the sun’s warm outer atmosphere, or corona, will appear as white light.
As the Moon continues its journey across the face of the Sun, the diamond ring, Baily beads, and partial solar eclipse will appear on the opposite side of the Moon from the Sun. completely reappears.
Where can I see the eclipse?
The total solar eclipse will be visible in Mexico, Canada and more than 10 US states, while the partial crescent-shaped solar eclipse is expected to be visible in 49 states, weather conditions permitting.
The eclipse will first appear over the South Pacific Ocean and begin its journey across North America. The Pacific coast of Mexico is the first point of totality on the track, expected at 11:07 a.m. PT (2:07 p.m. ET).
The trail will continue through Texas, Oklahoma, Arkansas, Missouri, Illinois, Kentucky, Indiana, Ohio, Pennsylvania, New York, Vermont, New Hampshire and Maine. It will then cross Canada through southern Ontario, Quebec, New Brunswick, Prince Edward Island and Nova Scotia, ending on the Atlantic coast of Newfoundland at 5:16 p.m. (3:46 p.m. ET).
Use our interactive map to determine how the eclipse will appear from your viewing location.
How can I view the eclipse safely?
According to NASA, the only time it is safe to see the sun without eye protection is during a total solar eclipse or during brief moments when the moon completely blocks sunlight and sunlight is not visible.
Otherwise, always wear certified ISO 12312-2 compliant eclipse glasses or use a handheld solar viewer before and after the total eclipse and during the partial eclipse.
Separately, you can observe the sun with a telescope, binoculars, or a camera with a special solar filter on the front that acts like eclipse glasses.
Looking directly at the sun can cause blindness or visual impairment. During a total solar eclipse in 2017, 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 eclipse glasses that did not meet doctors’ safety standards. There is no cure for solar retinopathy. It may get better or worse, but it is a permanent condition.
Sunglasses will not work as a substitute for eclipse glasses or sunglasses, which are 100,000 times darker and comply with the international safety standard.
According to The Planetary Society, the lenses of solar eclipse glasses are made of black polymer, or resin, infused with carbon particles that block nearly all visible, infrared and ultraviolet light. Sunglasses do not block infrared radiation.
For safe manufacturers and vendors 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 move away from the sun before taking them off again. Always keep an eye on children wearing eclipse glasses to make sure they do not take them off when looking at the sun.
If you normally wear glasses, put them on and place eclipse glasses over them or hold a hand-held viewer in front of them, according to the American Astronomical Society.
According to NASA, do not look at the sun with any unfiltered optical device (camera lens, telescope, binoculars) while wearing eclipse glasses or using a handheld solar viewer.
Considering how concentrated they can be in an optical device, the sun’s rays can still burn and cause serious eye damage by getting through the filter on glasses or goggles.
If you bought eclipse glasses to view the “ring of fire,” protect your eclipse glasses and viewers from April’s total solar eclipse by storing them in an envelope or original packaging at room temperature to prevent scratches.
What we can learn from eclipses
Eclipses give scientists 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,” NASA program scientist Kelly Korreck said in a statement. “They helped us make the first detection of helium, provided us with evidence for the general theory of relativity, and allowed us to better understand the Sun’s impact on the Earth’s upper atmosphere.”
One of the projects will rely on NASA’s high-altitude research aircraft to take images of the eclipse from 50,000 feet (15,240 meters) above the Earth’s surface to capture never-before-seen 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 annular and total solar eclipses to see how these events change the way radio waves travel. Operators in different locations will 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, or ionosphere, which allows radio communications to travel farther. However, this may change when the moon blocks the sun.
Both scientists and citizen scientists plan to observe the sun’s most active regions as it passes over the moon during both eclipses, using the Goldstone Apple Valley Radio Telescope.
The Sun is currently approaching solar maximum towards the end of this year, and scientists are keen to capture this peak of activity through a variety of observations that can only occur during eclipses.
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