An eclipse is simply the shadow cast by one body upon another, when
it passes in front of a source of light. There are two categories of
eclipse of interest to observers on the Earth, both of which owe their
existence to the fact that the Moon orbits around the Earth:
Lunar and Solar eclipses.
- A Solar eclipse occurs when the Moon passes between the
Earth and Sun; this happens at the New Moon,
and the effect is that
observers on the side of the Earth facing the Sun (i.e. the side which
is in daytime) have their view of it cut off, either partly or
completely.
- A Lunar eclipse occurs when the Earth passes between the
Full Moon and Sun (or, to look
at it another way, when the Moon passes
"behind" the Earth), and is visible at night as a shadow cast on the
Moon. A lunar eclipse can be quite beautiful; the full moon is seen
in shadow, and often appears a deep red colour.
The following pages provide more detail on the workings of
eclipses:
For those who are interested in delving a little deeper into the science,
here is some more detailed information:
