A date used as a reference to describe a set of orbital elements. It's required as orbital elements such as the angle of a planet's inclination or its eccentricity vary with time due to perturbations. The current epoch is J2000.0, which is measured from January 1, 2000 at 12:00 terrestrial time.

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Sky Highlights - April 2017

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Current Moon Phase

CURRENT MOON

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