The zodiac is a belt-shaped region of the sky that extends approximately 8° north and south of the ecliptic, the apparent path of the Sun across the celestial sphere over the course of the year. Also within this zodiac belt appear the Moon and the brightest planets, along their orbital planes. The zodiac is divided along the ecliptic into 12 equal parts ("signs"), each occupying 30° of celestial longitude. These signs roughly correspond to the astronomical constellations with the following modern names: Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius, and Pisces.
The Earth's orbit around the Sun causes the apparent motion of the latter along the ecliptic (red). Earth is axially tilted 23.4° relative to this plane; its equator, extended to the stars, is shown in light blue.
Astrophotos of the twelve zodiac constellations
A sixth-century mosaic zodiac wheel in synagogue Beth Alpha incorporating Greek-Byzantine elements, Israel
The 1st century BC Dendera zodiac (19th-century engraving)
The ecliptic or ecliptic plane is the orbital plane of Earth around the Sun. From the perspective of an observer on Earth, the Sun's movement around the celestial sphere over the course of a year traces out a path along the ecliptic against the background of stars. The ecliptic is an important reference plane and is the basis of the ecliptic coordinate system.
Image: Four Planet Sunset hao annotated
