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Leo the Lion
You can look at a calendar to check when spring will come.
However, 2,000 years ago, people looked at the sky to check
if spring was coming. They looked to the stars. A star is a
huge, hot, bright ball of gases. These people were looking for
a particular group of stars. Stars can be grouped together in
sets to form a pattern. The pattern is called a constellation.
These people were looking for a constellation known as Leo
the Lion.
This constellation got its name because the ancient Greeks
and Romans thought that the stars formed the outline of a
lion. This is one of the easiest constellations to identify. Leo’s
head looks like a backward question mark. A star that forms
one of Leo’s legs is one of the brightest stars in the night sky.
If you watch this constellation, it appears to move slowly
across the sky. This is true of all the constellations. However,
the constellations are not really moving. We are. Earth’s
rotation makes it seem as if the constellations are moving.
Just think how trees can appear to move if you are spinning
around in a forest.
As Earth spins, Leo the Lion appears over
the Northern Hemisphere at the
beginning of spring. In other words,
during the spring Earth is tilted so that
the Northern Hemisphere faces this
constellation in space.
During the other seasons, Earth is tilted
so that other constellations appear in the
Northern Hemisphere. In summer, you
can see Scorpio the Scorpion. In fall, you
can spot Pegasus the Flying Horse. In
winter, you can observe Taurus the Bull.
That leaves only 84 more constellations to
identify in the night sky.
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