What fundamentally defines the ecliptic in celestial mapping?

Answer

The plane of Earth’s orbit around the Sun projected onto the sky.

The ecliptic is defined as the projection of the Earth's orbital plane onto the celestial sphere. It acts as a reference line because the Moon and major planets also orbit near this plane.

What fundamentally defines the ecliptic in celestial mapping?

#Videos

The Ecliptic: Crash Course Kids #37.2 - YouTube

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