Shatapatha Brahmana 8.5.4.2

8.5.4.2

yadvevāṣāḍhāyai | iyaṃ vā aṣāḍhāsāvāditya stomabhāgā amuṃ tadādityamasyām pratiṣṭhāyām pratiṣṭhāpayati

And, again, as to why (on the range) of the Ashâdhâ;--the Ashâdhâ, doubtless, is this (earth), and the Stomabhâgâs are yonder sun: he thus establishes yonder sun upon this earth as a firm foundation.