If an observer were standing on the equator, which of these positions in the sky would pass through their zenith at some time in one 24-hour period?
A) north celestial pole, which is the perpendicular to the celestial equator
B) position of the Sun at summer solstice
C) vernal equinox, or 0 hours right ascension, 0° declination
D) ecliptic pole, or perpendicular to the ecliptic plane

Question

Quizplus · Accepted Answer

The vernal equinox, or 0 hours right ascension, 0° declination, is the only position listed that is directly on the celestial equator. Since the zenith of an observer standing on the Earth's equator aligns with the celestial equator, only objects located on the celestial equator (like the vernal equinox) can pass through their zenith.

If an Observer Were Standing on the Equator, Which of These