Home >> Science & Nature >> Astronomy

Facts About an Eclipse of the Sun

An eclipse of the Sun occurs when the moon passes between the Earth and the Sun, causing the shadow of the Moon to fall upon the Earth. The angle of the Moon's orbit is such that this happens infrequently, but astronomers have been able to map out when solar eclipses occur down to the second.

Umbra and Penumbra
- The umbra is a term that describes that part of the Earth where the Moon's shadow totally obscures the Sun. The penumbra is that part of the shadow that can only partially block out the Sun from someone on the ground.
Total Eclipses
- A total eclipse is one where the entire disc of the Sun is blocked out by the Moon. The view of such an event is limited to a very narrow area where the path of the shadow falls across the Earth.
Partial Eclipses
- A partial eclipse can be seen over a much broader area than a total eclipse. The Moon and the Sun are not in the exact position, so that a total eclipse may occur and only a portion of the Sun will be obscured.
Corona
- During a total solar eclipse, the corona of the Sun becomes visible. The corona is the glowing outer atmosphere of the Sun; sometimes huge solar flares exploding off the star's surface can be observed during a total eclipse.
Future Eclipses
- Astronomers have solar eclipses predicted well into the future. The paths of these events are determined so that scientists can go to where a total eclipse will be visible in order to study the phenomenon.

Astronomy