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The Moon
The silvery moon is the best subject to view with your telescope. As
Earth’s nearest neighbor, it’s about a quarter million miles (402,000 km)
away. That may sound like a long distance, but it’s close enough that
your telescope will reveal a fascinating lunar landscape of craters,
plains, and mountain peaks.
Here are a few interesting lunar features to look for:
Mare Crisium
Mare Crisium (“Sea of Crises”) is actually a huge plain formed when great
lava flows cooled and hardened on the moon’s surface.
Crater Copernicus
Crater Copernicus is a bright crater with a huge encircling ring of debris
that was thrown out of the crater when it was formed by an impacting
meteor more than 100 million years ago. It is 60 miles (97 km) across
and more than 2 miles (12,600 feet, or 3,840 m) deep.
Crater Tycho
Bright streaks or rays, best seen during a full moon, emanate from this
crater. The rays indicate that this is a young crater. Over time, meteors
constantly bombarding the crater’s surface will cause the rays to
disappear. Crater Tycho is 56 miles (90 km) across and almost 14,000 feet
(4,267 m) deep.
Crater Grimaldi
This large crater looks elliptical in shape, but it is actually circular. It
appears to be elliptical because we see it on the western horizon of
the moon, which is curving away from us. This effect is called
foreshortening. Crater Grimaldi is about 140 miles (225 km) across
and 10,500 feet (3,200 m) deep.
E
N
S
W
Mare
Crisium
Crater
Copernicus
Crater
Tycho
Crater
Grimaldi
© Copyright 1982 The Royal Astronomical Society of Canada
Note: This map, like
your telescope,
shows a mirror image
of the moon.
