If A constellation is on the "ecliptic" is it on the celestial equator?

False. Only as an observer on Mercury would define his own "ecliptic" and his own "celestial equator" would this be true, because only Mercury has zero tilt of its axis relative to its orbit perpendicular line, due to a tidal connection with the sun.





Earth, where 99% of all observers are, is a planet with an axial tilt of 23 degrees.



Only the equinox sun constellations are on in theory both the ecliptic and the celestial equator. In practice, since the constellations span broad regions of the sky, about half of the ecliptic constellations are also on the celestial equator (Aquarius, Pices, Taurus, Leo, Virgo, and Ophiuchus).If A constellation is on the "ecliptic" is it on the celestial equator?No...



The ecliptic is the apparent path that the Sun traces out in the sky during the year, appearing to move eastwards on an imaginary spherical surface, the celestial sphere, relative to the fixed stars. In more accurate terms, it is the intersection of the celestial sphere with the ecliptic plane, which is the geometric plane containing the mean orbit of the Earth around the Sun.

As the rotational axis of the Earth is not perpendicular to its orbital plane, the equatorial plane is not parallel to the ecliptic plane, but makes an angle of about 23掳26', which is known as the axial tilt (or obliquity of the ecliptic).

The intersections of the equatorial and ecliptic planes with the celestial dome are great circles known as the celestial equator and the ecliptic respectively.

The intersection line of the two planes results in two diametrically opposite intersection points, known as the equinoxes. The equinox that the Sun passes from south to north is known as the vernal equinox or first point of Aries.

The name ecliptic arises because eclipses occur when the full or new Moon is very close to this path of the Sun.If A constellation is on the "ecliptic" is it on the celestial equator?The ecliptic is tilted 23.5 degrees with respect to the equator, so they cross twice, once in Aries and once in Virgo. The other constellations on the ecliptic are not on the equator, and the other equatorial constellations, such as Orion, are not on the ecliptic.