// Package sun 太阳位置、升落、晨昏朦影、均时差、真太阳时、视高度角、视差角、视直径与日面物理星历；角度单位为度。
// Package sun covers solar position, rise/set, twilight, equation of time, apparent solar time, apparent altitude, parallactic angle, diameter and solar physical ephemeris; angles are degrees.
package sun