What is Annular Solar Eclipse?

KARACHI: Most of Asia will experience the last solar eclipse of the year on Thursday morning along with some parts of eastern Africa and northern Australia. A small region will witness an annular solar eclipse.

Sun Eclipse

A solar eclipse happens when the moon, orbiting the Earth, comes in between the sun and the Earth, due to which the moon blocks the sun’s light from reaching the Earth, causing an eclipse of the sun or a solar eclipse. There are three types of eclipses.

Total Solar Eclipse

A total solar eclipse happens when the moon appears large enough to cover the entire face of the sun. A total solar eclipse is visible only from a small area on Earth. A total solar eclipse happens when the sun, moon and Earth are in a direct line.

Partial Solar Eclipse

Partial solar eclipse occurs when the shadow of the moon appears on a small part of the sun.

During a solar eclipse the moon casts two shadows on the Earth, the first one is called the umbra, which gets smaller as it reaches the Earth. The second one is called the penumbra, which gets larger as it reaches the Earth. According to researchers, people standing in the umbra see a total eclipse and those standing in the penumbra see a partial eclipse.

Annular Solar Eclipse

An annular solar eclipse happens when the moon is farthest from the Earth, which is why it seems smaller. In this type of an eclipse, the moon does not block the sun completely, but looks like a "dark disk on top of a larger sun-colored disk" forming a "ring of fire".

In this type of eclipse, the moon covers the sun's centre, leaving the sun's visible outer edges to form a "ring of fire" — around the moon.

During an annular eclipse, experts use ground and space instruments to view this top layer when the sun’s glare is blocked by the moon.

But today, the moon will be near apogee, the point in its orbit when it is farthest away from the Earth. As a result, the moon will not quite be large enough to cover the entire sun, leaving behind a ring of light.

Safety

According to experts and the researchers, the sun can be viewed safely using the naked eye only during a total eclipse, while during partial and annular solar eclipses, the sun should not be viewed without proper equipment and techniques.