Matsya Purana — The Slaying of Jambha and the Rise of Tāraka: Divine Battle Formations
ततो ऽम्बुधय उद्भूतास् ततो नष्टा रविप्रभा ततस्तमः समुद्भूतं नातो ऽदृश्यन्त तारकाः //
tato 'mbudhaya udbhūtās tato naṣṭā raviprabhā tatastamaḥ samudbhūtaṃ nāto 'dṛśyanta tārakāḥ //
Then the oceans surged up; then the radiance of the Sun vanished. Thereafter darkness arose everywhere, and from that point the stars were no longer seen.
It describes classic pralaya portents: waters overwhelm the world, sunlight fails, and the sky becomes so dark that even stars are not visible—signaling an advancing cosmic dissolution.
In the Matsya–Manu framework, recognizing such omens supports dharmic preparedness—protecting dependents, preserving sacred knowledge, and following divine instruction (as Manu does) rather than clinging to ordinary routines when dissolution is imminent.
No direct Vastu or temple-building rule is stated; the ritual takeaway is the emphasis on cosmic inauspiciousness (loss of solar light, pervasive darkness), which in Purana practice signals a time for protective rites, restraint, and adherence to prescribed emergency dharma rather than new constructions.