What is the ecliptic of the celestial sphere?
The ecliptic of the celestial sphere is the counterpart of the ecliptic of the earth’s sphere. Since the Earth’s ecliptic is inclined to the Earth’s Equator by 23.50 the ecliptic of the celestial sphere is also inclined by 23.50. Generally, when we say “the Ecliptic” we mean the ecliptic of the celestial sphere otherwise specified.
The ecliptic is therefore a circumferential line or great circle on the celestial sphere, titled to the celestial equator at an angle of 23.50.
What are the North Pole of Ecliptic and the South Pole of Ecliptic?
Just as the ecliptic can be visualized as the celestial equator displaced on the celestial sphere by 23.50, we can visualize the north and south celestial poles to be correspondingly displaced by 23.50 on the celestial sphere to form respectively the North Pole of Ecliptic and the South Pole of Ecliptic.
What is the significance of the ecliptic, the equinoxes and the solstices?
These parameters have been closely related to the changes of seasons on Earth since ancient times.
What are the equinoxes?
The two times in each year when day and night are of equal duration are called equinoxes. The ecliptic intersects the celestial equator at two points, called the points of summer or vernal equinox or “Vasanta Sampaat” (which occurs on 21st March) and the autumnal equinox or “Sharad Sampaat” (which occurs on 22nd September respectively.
What are the solstices?
The points midway between the equinoxes are called the points of summer solstice (which occurs on 21st June) and the winter solstice (which occurs on 22nd December).
What is the ecliptic of the Earth’s sphere?
The plane of Earth’s equator is titled by 23.50 with respect to the mean plane of the planets; hence the Equator is also titled by 23.50 the ecliptic of Earth’s sphere refers to an imaginary, circumferential line around the Earth situated in the mean plane of the planets, or equivalent to the Equator titled by 23.50.
