Satellite Dataflow Vocabulary

1995, 1996 The Regents of the University of California

Depending on your grade level, the following terms may need to be defined and given further explanation.


A body that revolves around a planet; a moon; a human-made device designed to be launched from the Earth into orbit around a planet or the Sun.


A region of the electromagnetic spectrum that is outside the visible spectrum of energy and cannot be detected by the human eye. That is, electromagnetic waves of frequencies higher than those of violet, but lower than those of x-ray.

The Electromagnetic Spectrum
Gamma RayX-RayExtreme UltravioletUltraviolet VisibleInfraredMicrowaveRadio


Rotation refers to the motion of an object spinning around its own axis. In a spherical object the axis passes through the center of the sphere. In a non-spherical object it is the line of symmetry about which the object turns.


Revolution refers to the motion of an object about another. This motion may trace a path that is circular or nearly circular. For example, the Earth revolves around the Sun and the Moon revolves around the Earth. The path the object takes is called the orbit.


An object in space which revolves about the Earth once every 24 hours is in a geosynchronous orbit about the Earth. This means that the object is always above the same spot on the Earth. In order for the object to revolve about the Earth in 24 hours, it must be approximately 26,000 miles from the Earth's center (22,000 miles from the surface of the Earth).

Data "Drop Out"

Data just stops flowing, a break in the transmission of information from the satellite.

Return to Lesson Plan Details

Return to Procedure (at "rotation")

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