Special moments to watch during the total eclipse on April 8

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when Total solar eclipse Tracks the path Across Mexico, the United States and Canada On April 8, viewers can expect many amazing moments.

During a total solar eclipse The moon completely obscures the face of the sun Briefly known as totality – the 32 million people in the United States who fall along the 115-mile-wide (185-kilometer) path of totality for the April event will have the opportunity to enjoy this full expression of the celestial eclipse. Scene.

It's worth taking some time to pause and enjoy this historic celestial event because a total solar eclipse won't be visible across the contiguous United States again until August 2044, and annular eclipses will win, where the moon can't completely block the sun. They will not appear in this part of the world again until 2046.

“Until you actually see (a total eclipse), it's almost impossible to describe,” said Dr. John Mulci, vice president for science at the Carnegie Institution for Science and director and head of the Carnegie Observatories. “When you see it all, you can see how it has had such a huge impact on humans over thousands of years. It's one of the most beautiful things that most people will ever experience.”

But the phases surrounding a total eclipse — including some phenomena stunning enough to earn their own names — are also unforgettable, eclipse experts say. Here's what to look for.

The Moon does not suddenly appear between the Earth and the Sun, but rather the event begins with a partial eclipse, in which the Moon appears to take a “bite” of the Sun. Depending on your location, the partial eclipse can last between 70 and 80 minutes NASA.

For those outside the path of totality, the main event will be the crescent-shaped partial eclipse, not the totality.

A partial eclipse is the longest phase within the path, but as the time of totality approaches, look for changes in the appearance of the sky.

“About 15 to 20 minutes before totality, the sky starts to get this really weird dreary color,” Mulcci said. “It's almost like gray because the sun is high in the sky, but it's almost completely obscured. It's not like twilight or sunset or sunrise when (the sun) is low in the sky. It's above you. And suddenly, you lose most of the sunlight, and it looks very strange.”

An eerily dark sky is a signal to sky watchers that a star show is about to begin. Just make sure you have eclipse glasses handy to safely view the sun before the event starts.

Mulcci said that two amazing phases occur in the last moments before the total eclipse.

As the Moon begins to cross in front of the Sun, the star's rays will shine around the valleys on the Moon's horizon, creating glowing droplets of light around the Moon called Bailey's beads. This phenomenon is named after the English astronomer Francis Bailey, who observed it during an annular eclipse on May 15, 1836.

As totality approaches, Bailey's beads will quickly disappear and make way for a “diamond ring,” a nickname for how they appear when a single point of light remains — like a giant, shiny diamond ring.

These two phases last less than a minute, Mulci said.

Then it was time for college.

The total phase of the April 8 eclipse is It is expected to remain double what it was in 2017 Because the moon is currently closer to the sun. Those along the path's center line will see a total eclipse lasting between 3½ and 4 minutes, according to NASA.

“All of a sudden, a total eclipse happens, and the corona appears,” Mulci said. “Even though it's dark, it's pretty cool.”

The corona is the Sun's extremely hot outer atmosphere, which emits a glow that can be seen around the Moon during an eclipse. Normally, the corona is harder to see because the Sun's surface is brighter. During the total eclipse, the corona will resemble white streams of light, according to the “The Verge” website. NASA.

During the 2017 eclipse, the Sun was approaching solar minimum, or the quiescent phase of our star's 11-year activity cycle. Now, the sun is getting closer Maximum solar powerWhen the sun is exceptionally active, Mulci said. The corona will likely appear brighter and fuller, and there may be a chance of spotting glowing, streamer-like rings of solar activity within the corona during the eclipse.

Viewers 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. Sudden darkness also causes Animals behave in unusual ways.

“We may start to see nocturnal behavior, such as crickets chirping or bats emerging, and animals stopping diurnal behaviors, such as birds roosting or flying insects landing,” said Dr. Andrew Farnsworth, a visiting scientist at the Cornell Laboratory of Ornithology.

After the total eclipse ends, the diamond ring and Bailey's beads will appear again briefly before the partial eclipse returns as the moon slowly moves across the sun.

It was just that Six years since a total eclipse crossed the United StatesThe path of the April 8 eclipse is completely different, as it heads from west to east.

On average, eclipses occur in the same place every 375 years, Molcci said.

He said we live at the right time to truly enjoy the spectacle of a total terrestrial eclipse.

While eclipses occur throughout the solar system, none of them are quite like those that occur in our universe.

The moon is about 400 times smaller than the sun, but the moon is also about 400 times closer to Earth than the sun, creating a “beautiful coincidence” that creates an eclipse when the three celestial bodies line up, Molcci said.

This alignment is called conjunction, or when three objects line up in space.

In the distant past, the Moon was much closer to Earth, which means it probably did not appear as fully formed as it does now. In another 60 million years or so, the moon will be so far away that it will never cover the sun, making this a rare moment in time, Mulci said.