A unit used in the measurement of angles, heavily used particularly in astronomy. Due to ancient Babylonian mathematics, we still divide a circle into 360 even units of arc and call each of these ...
A table listing specific data of a moving object, as a function of time. Ephemerides usually contain right ascension ("R. A. " in these web pages) and declination ("Decl. " in these web pages), ...
Determined in principle from the sun's apparent annual motion, ET is the numerical measure of uniform time, which is the independent variable in the gravitational theory of the earth's orbital ...
20 用語
