Commentary Purg I 26

Our northern hemisphere is 'widowed,' deprived of the sight of these stars, because, as Chiavacci Leonardi suggests in her commentary (DDP Chiavacci.Purg.1.26), it is like the 'widowed' Jerusalem of Jeremiah (Lamentations 1.1), separated permanently from its original condition of unalloyed goodness (the condition, we may sometimes forget, that preceded that of original sin).  Those who argue that our 'widowhood' signifies that we know no goodness are defeated by the fact that some humans are indeed virtuous.  What we have lost is more primitive and total than acquired virtue: absolute innocence.

      Casella (Case.1949.1) argues that the southern sky represents the Christian active life, one of permanent prayer, while the northern heavens stand for our mortal life in consequence of the first sin.