Bhagavad Gita Chapter 8.25
dhūmo rātris tathā kṛṣṇaḥ
ṣaṇ-māsā dakṣiṇāyanam
tatra cāndramasaḿ jyotir
yogī prāpya nivartate
Translation
The mystic who passes away from this world during the smoke, the night, the fortnight of the waning moon, or the six months when the sun passes to the south reaches the moon planet but again comes back.