What characteristic determines if a constellation is considered part of the Zodiacal band?
Answer
Its boundaries cross the ecliptic.
A constellation belongs to the Zodiac if its defined boundaries intersect the imaginary line traced by the Sun's apparent yearly path across the sky.

#Videos
The Ecliptic: Crash Course Kids #37.2 - YouTube
Related Questions
What fundamentally defines the ecliptic in celestial mapping?What characteristic determines if a constellation is considered part of the Zodiacal band?Besides the Sun, which celestial bodies primarily appear to travel along or very close to the ecliptic line?What celestial event corresponds to the ecliptic intersection point at $180^ ext{circ}$ longitude?What results from the Earth's axial tilt of approximately $23.5^ ext{circ}$?Which constellation must the Sun physically cross the boundaries of, leading to a count of thirteen zodiacal constellations astronomically?What phenomenon causes the Sun's current astronomical location to differ from the constellation corresponding to its traditional astrological sign?Why are constellations like Leo obscured during the Northern Hemisphere summer months?How close to the ecliptic is the Moon always found, making it a useful tracking marker for solar system objects?The traditional division of the $360^ ext{circ}$ ecliptic into twelve astrological signs is based on what division size?