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Orbital objects are those man-made objects placed
into a
near-periodic orbit in which they move mainly under the
gravitational influence of one
celestial body, such as the
earth,
sun, another
planet, or a
planet's moon or those objects used to
place another object into
space.
Space junk is those objects which
are deliberately or accidentally allowed to float around space as
their
orbits decay and they burn up during
reentry. The balance
between
velocity and gravitational pull on an object control the
orbit. Many types of orbits exist, but
most
artificial satellites orbiting Earth travel in one of four
types: (1)
high altitude,
geosynchronous; (2)
medium altitude, (3)
sun-synchronous,
polar; and (4)
low altitude. Most orbits of these
four types are
circular. |
