Space Travel
22, May, 2012

Space exploration began with the launch of Sputnik and Astrophysics was born as the application of physics to the phenomena observed by Astronomy, which etymologically means laws of the stars.

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Term Definition
Hertzsprung Gap
A region on the Hertzsprung-Russell diagram, between the giant branch and the main sequence, where very few stars are represented. The gap reflects a general absence of giant stars of spectral types F and G, because the stage in the evolution of a star when it is observable as a giant of this type is very short. Thus at any one time, relatively few such stars exist.