Cause of an Eclipse
Name: janette l gubala
Date: 1993 - 1999
What makes an eclipse occur?
Eclipses occur when one astronomical object gets in the way of another,
so that the second objects light is blocked from reaching the earth. In a solar
eclipse, our moon gets between the earth and the sun, and blocks the light from
it for a while.
It's actually a rather remarkable coincidence that the moon and the sun are
roughly the same angular size right now, so that this is possible but rare (and
very spectacular). It's thought that trying to understand and predict solar
eclipses was one of the motivations for the development of astronomy thousands o f years ago.
In lunar eclipses the earth gets between the sun and the moon, so that the moon
becomes darker as we see it from earth. There are all sorts of variations on
these eclipses where only part of the object is blocked by the other - this
happens because the orbit of the moon is not a perfect circle and is not quite p erfectly aligned with
the earth's orbit about the sun.
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Update: June 2012