Download The most obvious feature on the Moon`s surface are its many craters

Near the magnetic poles, these
particles sometimes leak into our
atmosphere, causing the gases to
glow. This is known as the aurora.
The most obvious feature on the Moon’s
surface are its many craters.
Most of the Moon’s craters are round,
implying that they were formed from impacts
by high-speed meteoroids.
Craters include features such as central
peaks, collapsed terrace walls, and ejecta
blankets.
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Close examination of moon rocks reveal tiny
microcraters less than one millimeter in
diameter.
The Moon’s surface
also has large, dark
gray plains called
maria.
Since these regions
have few impact
craters, the lunar
surface here is
relatively young
compared with the
lighter surrounding
terrain.
From Earth, maria appear to be smooth regions on the lunar
surface. However, close-up photographs reveal small craters
and occasional cracks called rilles.
CLOSE-UP VIEWS FROM A
LUNAR ORBITER
APOLLO 15 MISSION
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A surprising find from
lunar orbiters is that the
side of the Moon facing
away from the Earth has
only one small mare,
while the rest is covered
with craters.
Missions to the
Moon have
revealed much
about its history.
An enormous boulder fractured
while sliding down a mountain
The Moon’s surface is covered with a
layer of powdered rock called regolith.
Lunar Rocks from Different Regions
MARE BASALT contains many holes,
suggesting that gas was dissolved in the
lava and solidified to create this rock.
ANORTHOSITE from the highlands is
an ancient rock believed to be part of
the Moon’s original crust.
IMPACT BRECCIAS are created from
debris fused together under high
temperature and pressure created by
impacts of space debris with the lunar
surface.
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Seismic experiments revealed
that the main regions of the
Moon’s interior mimic those of
the Earth, but in different
proportions.
Water ice may exist in the polar
craters, where the energy
received from the Sun is
insufficient to melt it.
The similarity in materials making up the Earth and Moon suggest
that the Moon may have been created from Earth material ejected
after a collision with a large planetesimal.
MOON
EARTH
This computer simulation shows how the
Moon could have been formed in a
collision between the Earth and a large
planetesimal..
planetesimal
The Earth and Moon orbit around their
center of mass, called the barycenter.
barycenter.
A wrench sliding across a
table rotates around its
center of mass.
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