Either half of the celestial sphere as divided by the ecliptic, the celestial equator, or the horizon.

半天球被黄道，天赤道或地平圈分成两半的天球的一半…

youdao

Either half of the celestial sphere as divided by the ecliptic, the celestial equator, or the horizon.

半天球被黄道，天赤道或地平圈分成两半的天球的一半…

youdao