As Earth orbits the Sun each year, the Sun appears to cross in front of more than a dozen constellations. As observers on a nearly circular path that takes 365 days to complete, we find the Sun moves ...
PASADENA, Calif. -- Lunar Orbiter 1, America's flying photographic laboratory, became the first U.S. spacecraft to orbit another heavenly body besides earth Sunday, when it went into a near-perfect ...
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