A rare sunset total solar eclipse will occur for millions of people on Wednesday

The grand stellar spectacle of the year has arrived. A total solar eclipse will be easily visible over parts of Europe on Wednesday.

A total solar eclipse occurs when the moon moves between the sun and Earth, casting a shadow on our planet that completely blocks the sun’s light from some areas of the world, according to NASA.

Major viewing locations in parts of Iceland, northern Spain and a small corner of northeastern Portugal will be in the path of totality, when the skies go momentarily dark as the sun completely disappears from view — creating a rare sunset eclipse for some, especially observers in Spain.

Meanwhile, a partial eclipse, in which only some of the sun’s light is blocked from view, will pass over the northern US, Canada, much of Europe and northwestern Africa. Check Time and Date to see when it will occur in your area.

Remember to wear certified eclipse glasses or use a handheld solar viewer to protect your vision any time the sun’s light is on display before, during or after the eclipse, and follow these safety tips to protect your vision.

For those who live outside the eclipse’s path, the European Space Agency will share a livestream of totality from Spain’s Astrophysical Observatory of Javalambre in Teruel. NASA is also hosting a live broadcast sharing views from across the path beginning at 1:15 p.m. ET.

Here’s what to expect during the eclipse.

When to see the eclipse

The excitement kicks off in a remote part of northern Russia where totality occurs midday local time. Sky-gazers in Greenland and Iceland will experience the longest duration of totality — about two minutes and 15 seconds — in the late afternoon and early evening.

But Spain and the northeastern tip of Portugal will experience a special spectacle as totality, which will last just under two minutes, occurs right before sunset. In León, totality will begin at 8:28 p.m. local time and end at 8:30 p.m.

Dr. Ryan French, solar astrophysicist at the Laboratory for Atmospheric and Space Physics in Boulder, Colorado, and coauthor of “Little Book of Eclipses,” is staying a few hours north of Madrid where totality will last for one minute and 45 seconds. He opted for a shorter eclipse experience with the likelihood of less cloud cover.

The partial eclipse phase that lingers after totality won’t conclude until 9:22 p.m. local time in León.

“For pretty much the entirety of Spain, by the time the sun sets sort of over the horizon, the total eclipse will have happened, but the sun will set in a partial eclipse, a beautiful sight seeing the sun set as a crescent sun,” French said.

And just as the eclipse excitement begins to subside, one of the best meteor showers of the year, the Perseids, will peak between Wednesday night and Thursday morning. NASA will host a live watch party with experts on YouTube beginning at 12 a.m. ET on August 13.

What happens outside the path of totality

For those living outside of the path of totality, a crescent-shaped partial eclipse, rather than a total eclipse, will be the main event.

The amount of exposed sunlight depends on how close viewers live to the path of totality. For example, people in the US will only see a small part of the sun covered by the moon, while Europe and northwestern Africa will experience a more dramatic cloaking of much of the sun, according to NASA.

“New York will see a 10% eclipse, so you know a very small slice of the sun missing,” French said. “But if you’re in Europe, obviously that slice is much larger. In the United Kingdom, which won’t actually experience a total solar eclipse until the year 2090, they’re actually getting a 95% eclipse for this event.”

The partial eclipse will occur in the morning for those in Alaska and northern Canada, in the afternoon for the northern US and eastern Canada, and in the evening for viewers in the UK, Ireland, Africa and mainland Europe, where the sunset eclipse phenomenon will occur.

What to watch for during an eclipse

The moon doesn’t suddenly appear between Earth and the sun — the event begins with a partial eclipse, in which the moon appears to take a “bite” out of the sun. Depending on your location, the partial eclipse can last between 70 and 80 minutes, according to NASA.

As the time of totality nears, look for changes in the sky’s appearance as it begins to eerily darken.

When the moon starts to cross in front of the sun, the star’s rays will shine around valleys on the moon’s horizon, creating glowing drops of light around the moon called Baily’s beads. The phenomenon was named for English astronomer Francis Baily, who noted them during an annular eclipse on May 15, 1836.

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As totality approaches, Baily’s beads will quickly disappear and make way for the “diamond ring,” a nickname for how the eclipse looks when a single point of light remains — like a glistening, giant diamond ring.

Then, it’s time for totality — the only safe time to remove eclipse glasses. The corona is the sun’s ultrahot outer atmosphere, and it emits a glow that can be seen around the moon during the eclipse. During the total eclipse, the corona will resemble white streams of light, according to NASA.

“The sky will have some sort of weird, twilighty, silvery glow about it,” French said.

If wildfire smoke persists in the path of totality, the corona, which is a million times fainter than the sun’s surface, may be too difficult to see through the haze, he added. But this should not be an issue for those in the path of the partial eclipse.

“Wildfire smoke may even enhance the experience, turning the sun a reddish color and making it easier to photograph without specialist camera filters,” French said.

Spectators may also be able to see a region of the solar atmosphere called the chromosphere, which will appear as a thin, pink circle around the moon.

Bright stars or planets such as Venus may shine in the dark sky, and the air temperature will drop as the sun disappears. The sudden darkness also causes animals to behave in unusual ways.

Remember to put your eclipse glasses back on immediately after totality ends. The diamond ring and Baily’s beads will briefly reappear before the partial eclipse returns as the moon slowly moves across the sun.

NASA advises not to look at the sun through any unfiltered optical device — camera lens, telescope, binoculars — while wearing eclipse glasses or using a handheld solar viewer. Solar rays can still burn through the filter on the glasses or viewer, given how concentrated they can be through an optical device, and can cause severe eye damage.

While everyone tries to photograph the actual eclipse, French prefers a different perspective if viewing the event with friends or family.

“Have somebody in your group position a phone pointing at yourselves and just get an authentic video,” French said. “Forget it’s there, set it up 20 minutes earlier and get a video of how your friends and family react. I think that’s a nice sentimental thing.”

If this awe-inspiring event already has you wanting more, mark your calendar and start making plans for August 2, 2027, when a total solar eclipse will cross southern Spain, Gibraltar, Morocco, Algeria, Tunisia, Libya, Egypt, Saudi Arabia, Somalia and Yemen — and will last up to more than six minutes.

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