optikë aktive

Exactly 365. 25 days, in which a century (100 years) is exactly 36525 days and in which 1900. 0 corresponds exactly to 1900 January 0. 5 (from the Julian-date system, which is ...

heliocentrik

Astronomy; General astronomy

Referring to the sun. A heliocentric orbit is one based on the sun as one of the two foci of the (elliptical) orbit (or as the center of a circular orbit); a heliocentric ...

datë juliane

Astronomy; General astronomy

The interval of time in days (and fraction of a day) since Greenwich noon on Jan. 1, 4713 BC. The JD is always half a day off from Universal Time, because the current definition ...

ekuinoks

Astronomy; General astronomy

Either of the two points (vernal, autumnal) on the celestial sphere where the ecliptic (which is the apparent path of the sun on the sky) intersects the celestial equator. Due to ...

shtrirje

Astronomy; General astronomy

Angular distance of a celestial object from the sun in the sky. In standard ephemerides, this is usually denoted by the Greek letter epsilon (or by the abbreviation "Elong. "). A ...

pjerrësi

Astronomy; General astronomy

One element of the astronomical coordinate system on the sky that is used by astronomers. Declination, which can be thought of as latitude on the earth projected onto the sky, is ...