Description of the solar system - Verse 109

Sūta said: This (mountain) has the illumination on the side of the world. Beyond the worlds, it is devoid of illumination. The inter-space between. Uṣā (Night or Dawn) and Vyuṣṭi (Morning) joins the Lokāloka accepted by the sun(?) Therefore, they call it Sandhyā (Twilight). Uṣā is remembered as night and Vyuṣṭi is remembered as the day, by the Brāhmaṇas