1. the north polar constellation can be seen in the southern hemisphere.
"As viewed from the North Pole, all fully visible constellations north of the celestial equator are circumpolar, and likewise for constellations south of the celestial equator as viewed from the South Pole."
2. the south polar constellation can be seen in the northern hemisphere.
"The southern constellations Carina, Centaurus, and Crux are found circling the south celestial pole and can be seen from southern latitudes at any time of year while remaining invisible for observers in most northern locations."
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