|
eclipse
|
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. |
| galaxy
|
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. |
| gravity
|
the
force by which a planet or other such body tends to draw objects
toward its center. |
| asteroid
|
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. |
| meteor
|
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. |
| meteorite
|
a
mass of stone or metal falling to earth from outer space; meteoroid.
|
| moon
|
any planet's natural satellite. |
| orbit
|
the curved path in which a planet, satellite, or spacecraft revolves
about another body. |
| planet
|
a
large, nonluminous celestial body, esp. one of the nine in the solar
system, that revolves around a star and often has one or more satellites. |
| satellite
|
a
heavenly body that revolves around a planet or other larger body;
moon. |
| black
hole |
a
hypothetical region or body in space, possibly the remnants of a
collapsed star, with such a strong gravitational pull that neither
light nor matter can escape. |
| zenith |
the
point in the sky that is directly over the head of the observer.
|
| comet |
a
heavenly body orbiting the sun, and having a nucleus surrounded
by a nebulous sheath that may form an elongated tail when the body
comes close to the sun. |
| constellation |
any
of eighty-eight groupings or patterns of stars named after the animals,
objects, or mythological characters they are thought to resemble.
|
