وَمِنَ اللَّيْلِ فَسَبِّحْهُ وَإِدْبَارَ النُّجُومِ
and also glorify Him during the night and at the receding of the stars.
Agha Ali Puya Commentary
Commentary on Quran 52:49
[Pooya/Ali Commentary 52:49] About spending a part of the night in prayers see Bani Israil: 78 and 79.