The Moon
28.2
Lunar Properties
 Lunar – pertaining to moon
 We have a large moon
compared to the size of
Earth
 Our moon is solid and rocky,
other moons are icy
Features
 Highlands – light colored
regions that are
mountainous and covered
with craters
 Maria – dark, smooth plains
 Impact craters – (all)
formed when objects from
space crashed into the
moon (no atmosphere)
Craters
 Ejecta – the material
that comes out of the
moon after an impact
(what was in the hole
before the impact)
 Rays – trails of ejecta
that radiate outward
from where the crater
hit
Craters on Earth/Moon
 Earth was hit with many objects just like the
Moon, erosion on Earth
 No erosion on the moon
Composition of the Moon
 Made of minerals like the
ones on Earth
 Breccia - Rocks that are
mostly silicates (salts with
silicon and oxygen) with
Calcium and Aluminum
History of the Moon
 Aged between 3.8 billion – 4.6 billion years old
 Regolith – a layer of loose, ground up rock
 formed during the first 800 million years from being
bombarded
 Maria – formed by lava coming up from the inside of
the moon and filling the areas hit
 Temperature varies
 As high as 127 degrees C in sun
 As low as -173 degrees C w/out sun
Moon doesn’t rotate on its axis, so we always see
the same side
Crust is twice as think on the far side of the moon
and almost completely covered with highlands
(farther the lava has to travel)
Layers of the Moon
 Crust – varies in thickness,
thickest on far side
 Upper Mantle – solid
 Lower mantle – partially molten
 Core – made of solid Iron
Properties
 Size
 Mass = 7.349 x 10^22 kg
 Radius = 1737.4 km
 Orbit Distance - 363,104 km
 27 days