The moon will blot out the sun for millions of people in a total solar eclipse, best seen from parts of Spain and Iceland, occurring on Wednesday, August 12.

Here is an explanation of the solar eclipse, where it will be visible and what to expect.

WHAT IS A TOTAL SOLAR ECLIPSE?

In a total solar eclipse, the moon passes between the sun and Earth, entirely covering the face of the sun along a small path of our planet's surface. This is called the "path of totality." The daytime sky darkens to a twilight-like level, and animals may alter their behaviour.

"If you're lucky to be right in that path, then you will see a very, very dark coin. That is the moon covering the sun", explained Dr Noelia Noël, astrophysicist at the University of Surrey.

TYPES OF ECLIPSES

There are four different types of solar eclipses - total, partial, annular and hybrid.

In a partial eclipse, “we will still see part of the sun, but the moon will be covering, a very good fraction of it”, said Dr Noël.

While an annular eclipse is similar to a total eclipse, “the size of the moon looks a little bit smaller compared to the size of the sun”, she added.

A hybrid solar eclipse occurs when the eclipse changes its appearance between annular and total eclipse as the Moon's shadow moves over the Earth's surface, according to NASA.

WHERE AND WHEN CAN YOU SEE THE AUGUST 2026 ECLIPSE?

The August 12, 2026 total solar eclipse will be visible in parts of Greenland, Iceland, northern Russia, the Atlantic Ocean, Spain, and a small corner of Portugal, according to NASA.

"For a total eclipse to be visible from Earth, we need to be right in the middle of the path where the sun, the moon and Earth are aligned”, said Dr Noël.

NASA says a partial eclipse will be visible across parts of the Northern Hemisphere, including parts of the northern United States, most of Canada, much of Europe and northwestern Africa.

HOW BIG ARE THE EARTH, MOON AND SUN?

The moon will cover the sun's face, as visible from Earth, only because the moon - in actuality much smaller than the sun - is so much closer to our planet. The moon's diameter is 2,159 miles (3,476 km), compared to the sun's diameter of about 865,000 miles (1.4 million km) and Earth's diameter of 7,918 miles (12,742 km).

SAFETY PRECAUTIONS

"In the moments before the total solar eclipse, you should only wear solar eclipse approved sunglasses”, cautioned Dr Noël.

Viewing an eclipse through a camera lens, binoculars or telescope without making use of a special-purpose solar filter can cause severe eye injury, according to experts.

They advise using safe solar viewing glasses or a safe handheld solar viewer, noting that regular sunglasses are not safe for viewing the sun. The only moment it is considered safe for people to remove eye protection during a total solar eclipse is the brief time when the moon completely blocks the sun's surface.

If you do not have access to specialised eye protection designed for solar viewing, you can use a colander to “project the shadows on a white piece of paper”, advises Dr Noël.

“Or you can actually drill holes on a sheet of paper and and put that against the sun, and then look down on the floor and see the shadows”.

WHAT CAN YOU EXPECT TO SEE DURING THE ECLIPSE?

A total solar eclipse unfolds in several distinct stages.

It starts with a partial eclipse phase as the moon begins to pass between Earth and the sun, partially blocking it and leaving the sun looking like it has a crescent shape.

In the subsequent Baily's Beads phase, points of light from the sun shine around the moon's edges because of the irregular lunar topography, producing small beads of light.

In the diamond-ring phase, the last bright sliver of the sun's visible surface appears beside the faint solar corona, creating an effect resembling a diamond ring. It occurs immediately before totality and again as totality ends.

After totality, the other phases repeat as the moon keeps moving along its path until the eclipse ends.

"From an experience point of view, if you're lucky enough to be in the path of the total eclipse, you will see the dark appearing and suddenly the birds will start chirping. The animals will be confused and and you will see a 360 sunset”, said Dr Noël.

She noted a temperature drop may also follow.

FUTURE ECLIPSES

An annular solar eclipse will occur on February 6, 2027 and be visible in parts of South America and Africa, according to NASA. A partial solar eclipse will be visible from large parts of South America, Africa, Antarctica, the South Pacific Ocean and the South Atlantic Ocean.

A total solar eclipse will occur on August 2, 2027 and be visible in southern Spain, North Africa, Saudi Arabia and Yemen. A partial eclipse will be visible in Europe, Africa, the Middle East, Southeast Asia, eastern Canada and parts of the north American continent.

Posted by: Alma Angeles/NET25 News

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