I think there is more than mathematical astronomy as indicated by other members of this forum. The Mantras and Brahmanas provide a piece of intrinsic evidence to this effect!

According to my knowledge, it has a strong connection with Prajāpati. 

I do not agree with the interpretation provided by Rama Sharma Acharya as he has failed to consider the apparent connection of this verse with Śatapatha Brāhmaṇa. 

We should remind ourselves time and again that the primary purpose of Mantras and Brāhmaṇa is yajñá. 

Certainly, anyone can arrive at a layered meaning employing his figments of imagination. Nevertheless, the primary purposes of Mantras and Brahmanas cannot be ignored during interpretation!

See for instance १.६.३.[३५] of Śatapatha Brāhmaṇa (1.6.3.35 and ff. )

> प्रजापतेर्ह वै प्रजाः ससृजानस्य । पर्वाणि विसस्रंसुः स वै **संवत्सर** एव प्रजापतिस्तस्यैतानि >**पर्वाण्यहोरात्रयोः** संधी पौर्णमासी चामावास्या **चर्तुमुखानि** - १.६.३.[३५]

>After Prajāpati had created the living beings, his joints were relaxed. Now >Prajāpati is the year (संवत्सर) and his joints are the two junctions of day and >night (पर्वाण्यहोरात्रयोः), the full moon and the new moon and the beginning of >seasons. He was unable to rise and the gods healed him by Havis and so on. 

I understand that I have provided a partial answer or rather hints. However, it hints a strong connection with Sayan's commentary and the original Rk.