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The Electromagnetic Spectrum
For thousands of years, humans have used their eyes to observe stars and planets. But scientists eventually discovered that visible light, the light that we can see, is not the only form of radiation. In 1852, James Clerk Maxwell proved that visible light is a part of the electromagnetic spectrum. The electromagnetic spectrum is made up of all of the wavelengths of electromagnetic radiation.
space probes
uscrewed vehical that caries tools to space to provied information
rockets
a vehical that takes us to space to see things with human eyes.
Satellite
is an object which has been placed into orbit by human endeavor. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon.
inertia
the tendency of an object to resist being moved or, if the object is moving, to resist a change in speed or direction until an outside force acts on the object
momentum
a quantity defined as the product of the mass and velocity of an object
apparent motion of stars
a apparent motion of stars is it appers the stars move but its actally its the earth is the one moving