What imaginary great circle on the celestial sphere represents the precise plane in which the Earth orbits the Sun?

Answer

The ecliptic

The ecliptic is defined as the apparent track traced by the Sun across the distant stars over one year, corresponding exactly to the geometric plane of Earth's orbit around the Sun.

What imaginary great circle on the celestial sphere represents the precise plane in which the Earth orbits the Sun?
sunastronomypathCelestial sphereecliptic