Ecliptic
The ecliptic is the path the Sun appears to follow across the sky in a year, marking the plane of Earth's orbit.
The ecliptic is the line across the sky along which the Sun appears to move over a year, against the background stars. It marks the plane of Earth's orbit. Because the other planets orbit in nearly the same plane, they too are always found close to the ecliptic, as is the Moon.
The constellations along the ecliptic are the zodiac constellations, such as Taurus, Gemini and Leo. Many meteor shower radiants lie near the ecliptic, because many asteroids and comets have low-inclination orbits, but others, such as the Quadrantids and Draconids, lie far from it.
The ecliptic is also where interplanetary dust is concentrated. On clear, dark nights, a faint cone of light, the zodiacal light, can be seen rising along the ecliptic after dusk or before dawn. This is sunlight scattered by dust grains, some of which eventually fall to Earth as micrometeorites.
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