Which constellations are not visible from North America?
Many. Here is a list for you. http://www.astromax.com/con-page/con-sth.htm
The constellations along or near the ecliptic, including the constellations of the Zodiac, are visible from most of north and south america. At high latitudes in either direction, the equatorial constellations will be pretty low on the horizon and may not be visible unless the terrain is fairly flat, or from high elevations such as mountain peaks.
The constellations near the plane of the ecliptic (the zodiacal constellations) are only visible at certain times of the year. The constellations towards the poles (N and S) are visible at all times of the year from their respective hemispheres. In the South, the Southern Cross would be one example and in the North the Great Bear (or plough) would be another.
Polaris, or the North Star, is always visible in the Northern Hemisphere. The entire sky rotates around it during the night. The Big and Little Dipper aka Big and Little Bear are visible, as Polaris is a part of the Little Dipper. Draco, Casseopia, and Capheus are also formations normally visible around the North Star. The other constellations vary with the seasons, see the star chart referenced.
Circumpolar constellations are visible all year long, depending on where you are viewing them from. At the north pole, or the south pole, some constellations are visible year-round, these are the circumpolar constellations. On the equator, there are no circumpolar constellations because of the earths rotation, that is why circumpolar constellations are at the "poles". Some of the circumpolar constellations can also be viewed from other parts of the same hemisphere, such as the big…
Some of them, yes. Constellations along the Zodiac can be seen from either hemisphere, but constellations well away from the celesial equator cannot be seen very far in the other hemisphere. For example, Ursa Major is not visible in Australia, and the Southern Cross is not visible in Europe or North America. Most of the "official" constellations were named by northern hemisphere astronomers, or European navigators sailing in southern waters. Look at how many southern…
Due to the rotation of the Earth, the constellations overhead in the day time (which are not visible as it is) are not the same ones visible at night. However, the constellations in today's day sky are the same constellations in the night sky 6 months from now, and the constellations in tonight's night sky are the same constellations in the day sky 6 months from now.