Meridianal coordinate system
From Wikipedia, the free encyclopedia
Meridianal coordinate system is a celestial coordinate system that deals with system of meridiator and meridians mounting on the celestial sphere. There are two types of important meridiator on the celestial sphere: Equinox meridiator and Solstice meridiator. Two meridiators will bisect at the poles.
Equator has the widest separation between the lines of meridian. As the latitude increases, the meridians are getting closer together and longitude are getting narrower. At the poles, the meridian lines will all intersect and don't have defining longitude.
Contents |
[edit] Equinox meridiator
Equinox meridiator is an imaginary line that goes around the celestial sphere by passing through both poles and equinoxes, exactly like the equator, but they are perpendicular. The intersection between the ecliptic is called equinox. The intersection between the equator and meridiator is called equinox virgin. Equinox meridiator can be divided into two parts: Spring Meridian and Autumn Meridian.
[edit] Spring Meridian
Spring Meridian is a part of the equinox meridiator, at which the celestial longitude is 0° (0h). This is the meridian of the First point of Aries, or vernal equinox. Equinox is the intersection between equator and the ecliptic. Vernal equinox is the intersection between Spring Meridian, equator, and the ecliptic, located in the constellation Pisces. The intersection between the equator and the Spring Meridian is called the midnight virgin because it is located in right ascension 00h 00m 00.00s, corresponding to midnight.
[edit] Autumn Meridian
Autumn Meridian is a part of the equinox meridiator at which the celestial longitude is 180° (12h). This is the meridian of the First point of Libra. The intersection between the equator and the ecliptic is located in the constellation Virgo. The intersection between Autumn Meridian and the equator is called noon virgin. While the intersection between the equator and the ecliptic is called autumnal equinox.
[edit] Solstice meridiator
Solstice meridiator is a meridiator that divide into two parts: Summer Meridian and Winter Meridian. Like Equinox meridiator, it passes over the poles and opposely, on the right angles of Equinox meridiator (6h apart). The intersection between solstice meridiator is called solstice and the intersection with equator is called solstice virgin.
[edit] Summer Meridian
Summer Meridian is a part of the solstice meridiator at which the celestial longitude is 90° (6h). This is the meridian of the First point of Cancer. It is the intersection between the ecliptic and Summer Meridian, located in constellation Taurus. When intersects the equator, it is called morn virgin in the constellation Orion. If intersects the ecliptic, it forms known as summer solstice.
[edit] Winter Meridian
Winter Meridian is a part of the solstice meridiator at which the celestial longitude is 270° (18h). This is the meridian of the First point of Capricorn. The intersection between Winter Meridian and the equator is known as eve virgin in the constellation Ophiuchus, while it intersects the ecliptic is called winter solstice in constellation Sagittarius.
