Describe the Moon, which orbits the Earth appearance as an object;
size, color and composition.

Hello,

The moon is 2,140 miles (3,476 km) around, or about one-fourth the
size of the Earth. (2,140 miles is about the distance from
Philadelphia to Spokane, Wash.) It weighs about 7.35x10^22 kg., or
about 1/81 of the Earth's mass (1).

The lunar surface is made up mostly of oxidized forms of metals,
especially silicon, aluminum, calcium, magnesium and iron (2).
Scientists think the moon's metal core is relatively small -- less
than 4 percent of the moon's total mass (3).

The "color" of the moon is subjective, dependant on the source of
light, the distance to the viewer, and what is between the viewer and
the moon. Ordinarily, it looks white or yellow from Earth, but can
appear orange during certain sky conditions. During an eclipse, it may
appear red. The actual material from the moon looks dark when brought
to Earth (4).

I hope this answer meets your needs. If not, please request
clarification.

(1) Zoom Astonomy, "The Moon"
http://www.enchantedlearning.com/subjects/astronomy/moon/

(2) Permanent, "Major Lunar Minerals"
http://www.permanent.com/l-minera.htm

(3) BBC, "Earth smask spawned Moon"
http://news.bbc.co.uk/1/hi/sci/tech/298157.stm

(4) Robert Roy Britt, "Coloring the Universe"
http://www.space.com/scienceastronomy/astronomy/color_universe_020625-1.html

The Moon, as seen from Earth, is about 30 seconds of arc (half a
degree) across. By a happy coincidence this is the same size as the
sun, hence we have solar eclipses.

The Moon appearing larger when it's nearer the horizon is an illusion
- it's got nothing to do with atmospheric refraction.

Ian G.

The surface gravity of the Moon is about 1/6 of the gravity at Earth's
surface. The 12 astronauts, explored 6 tiny locations on the moon,
perhaps a millionth part of the moon's surface. So we are partly
guessing what the rest of the moon is like. We have lots of pictures
with resolution good enough to see snall hills and all larger features
that can be photographed from about 100KM = 60 miles above the
surface, except the North and South Pole regions are not as well
photographed. Colors are rare, just various shades of grey.  Neil

2140 miles is the moon's diameter, making it about 6724 miles around :)