Imagine if we trace a path of the Sun, Moon and planets about the sky, we will have the ecliptic plane. We "see" the ecliptic arc across our sky because of Earth's tilt, but what this is in reality is the orbital planes of all the planets about our Sun.

The image above demonstrates the ecliptic as viewed from San Francisco, California in December. Seasonal and latitude changes will effect where this arc appears - seasonal changes because of the lower in the winter, higher in the summer changes due to Earth's orbit about the Sun (more on this in the Earth section).

Back to Top | Image Credit: Starry Night v. 4.5