As far as I understand, since the the 12 zodiac constellations (astrological signs) 'surround' the earth, hence it's possible to see by naked eyes a group of 6 astrological signs (only) simultaneously - from one hemisphere.
Assuming it's correct, my question is how many of the 12 zodiac constellations are possible to see in one single night?
Since the earth moving constantly, it seems that the answer depends on the time and season, but assuming that the day and the night are equal in time (March 21th), what will be the answer? To my logic it should be 12 but I am not sure about it.