the point in the sky that is directly over the head of the observer.
Starts with
C
a heavenly body that revolves around a planet or other larger body; moon.
Starts with
D
Starts with
E
the force by which a planet or other such body tends to draw objects toward its center.
Starts with
G
any of thousands of celestial bodies with diameters between one and five hundred miles that revolve around the sun in orbits located mostly between those of Jupiter and Mars; planetoid.
Contains
I
Contains
K
Starts with
L
Starts with
M
a small mass, speck, or remnant of matter traveling through space or falling to earth, or the fiery streak in the sky made by the friction of its passage through the earth's atmosphere; meteorite or meteoroid.
Starts with
N
Starts with
O
at a particular observation point, the blocking of light from one celestial body by another, such as the eclipse of the sun by the interposition of the moon, or the eclipse of the moon by the earth's coming between the sun and moon
Starts with
P
a system of billions of stars and other matter held relatively close to each other by gravity and separated from other such systems by vast distances.
Contains
R
Starts with
S
any of eighty-eight groupings or patterns of stars named after the animals, objects, or mythological characters they are thought to resemble.
Starts with
T
Contains
U
Contains
V
Contains
X
Contains
Y
Starts with
Z
the curved path in which a planet, satellite, or spacecraft revolves about another body
