Earthquake — Why it happens?

An earthquake is a sudden movement of the earth's crust caused by an abrupt shift of rock along a rupture in the Earth, called a fault.

The crust is the thin outer layer of the Earth and is made of several plates that covers the entire surface of the globe. Since they are all moving they rub against each other in some places, sink beneath each other in others or spread apart from each other.

The sudden movements inside the earth that push against the Earth's fragile crust break the rocks suddenly. This set off a concentric shock waves to move out from that point and releases pressure that has accumulated within the rock. An earthquake is the vibration that radiates out from the breaking rock. Most of the earthquakes occur in the areas where plates collide or try to slide past each other.

Solar Eclipse — A Strange Phenomenon

Solar eclipse occurs when the Moon circling around the Earth passes between the Sun and the Earth obstructing the Sun's light. When the sun is blocked off by the moon a shadow of the moon is cast over the earth's surface. This is what a solar eclipse really is. This usually happens at New Moon.

The moon circles our planet about 29 and a half days, but this does not mean that we should have a solar eclipse every month. This is so because the moon circles the Earth at an angle, approximately 5 degrees relative to the Earth-sun plane. As a result, the Moon's cast shadow usually misses Earth as it passes our planet. This makes solar eclipses relatively rare at any location. At least two or up to five solar eclipses can take place on Earth each year.

The Moon's two shadows are the umbra and the penumbra. You can see a total blocking of the sun's light or a total solar eclipse over which the umbra passes. And you can see only a partial blocking of the sun if you are within the area of penumbra shadow.