Recently, parts of Kerala, Karnataka and Tamil Nadu witnessed an annular solar eclipse. Rest of the country witnessed a partial solar eclipse.
About Solar eclipse
Solar eclipse happens when the moon, while orbiting the Earth, comes in between the Sun and the Earth, thereby blocking the sun’s light, fully or partially.
There are four types of eclipses:
Total solar eclipse
Total solar eclipses are rare at any particular location because totality exists only along a narrow path on the Earth’s surface traced by the Moon’s full shadow or umbra.
It happens when
- it is New Moon
- the Moon is near perigee (the closest point of the Moon from Earth)
- and the Sun are aligned in a straight (or nearly straight) line.
It is visible only from a small area on Earth.
People who are able to view the total solar eclipse are in the centre of the
moon’s shadow as and when it hits the Earth.
Partial solar eclipse:
In it the shadow of the moon appears on a small part of the sun.
Annular solar eclipse (ASE):
o It occurs when the angular diameter of the Moon falls short of that of the
Sun so that it cannot cover up the latter completely.
Since the moon does not block the sun completely, it looks like a “dark disk on top of a larger sun-colored disk” forming a “ring of fire” (or annulus).
For an ASE to take place, three things need to happen-
- there should be a New Moon
- the Moon should be at or very near a lunar node so that the Sun, Moon and the Earth all are in a straight line
- the Moon should be near the apogee (the farthest point of the Moon from Earth) so that the outer edge of the Sun is visible.
o During one of the phases of the ASE a phenomena called Bailey’s Beads’ are visible. This is a thin fragmented ring caused by passage of sunlight through the rough edge of the Moon.
o This is the only time when one can find two shadows for everything in all the sides under the sunlight because the light source during Annularity is a giant illuminating ring.
o During an ASE, NASA uses ground and space instruments to view top layer of the sun or corona when the sun’s glare is blocked by the moon.
o During partial and annular solar eclipses, it is dangerous to view sun without proper equipment and techniques. Not using proper methods and equipment for viewing can cause permanent eye damage or severe visual loss.
This is a very rare eclipse where the eclipse will only be annular for the first few seconds. For the rest it will be a total eclipse.