What is an Eclipse

You know you’re seeing a solar eclipse when the sky goes dark in the middle of a sunny day. Slowly a dark circle will form on the Sun, eventually blocking most of the fiery disc before growing smaller and then disappearing. You have just witnessed an eclipse. Now let’s learn about the science behind an eclipse.

An eclipse is an event that occurs in outer space when one object in space moves into the shadow of a second object. The shadow is an area beside a planet, moon, asteroid or other object where the Sun’s rays do not penetrate, as they are blocked by that object. For example, the Earth will always have a shadow in the area directly opposite from our sun, much like your body will cast a shadow in the opposite direction of the sun. When another object moves into that shadow, the sun’s light is blocked either partially or completely, causing an eclipse.

The two types of eclipses that we can witness from Earth are solar and lunar. They both involve the sun, the Earth, and Earth’s Moon. A solar eclipse is an event whereby Earth’s Moon partially or fully blocks the Sun’s rays, creating darkness on Earth in the path of the Moon’s shadow. Lunar eclipses occur when the Earth blocks some or all of the sun’s rays from hitting the Moon’s surface. Generally speaking, lunar eclipses will occur more often than solar eclipses. After all, the Earth is much larger than the Moon, which creates more opportunities for the Earth to block the sun’s rays than the opposite to occur. It’s worth noting that lunar eclipses will only occur during a full moon, when the Moon is on the far side of the Earth, opposite the Sun.

As noted above, eclipses can be full or partial. A full eclipse occurs when one object completely hides the Sun’s rays from another. Due to the angle of tilt of the Earth on its axis, as well as the position of the Moon in space, an eclipse may only partially block the sun’s rays while permitting some sunlight to penetrate to the Earth’s surface. It is also possible that some parts of the Earth’s surface will experience partial eclipse, a full eclipse, or no eclipse at all at a given point in time, all dependent upon the position of the Earth, the Moon, and the Sun in space.

In the past some people attributed mystical or magical properties to an eclipse. There’s never been any proof of that, but it’s still an intriguing phenomenon. One final thought: never look directly at an eclipse! There’s still enough radiation coming from the sun to permanently damage your sight, even during an eclipse.