Rig Veda 1.123.8

Sanskrit text [Accents, Plain, Transliterated]:

स॒दृशी॑र॒द्य स॒दृशी॒रिदु॒ श्वो दी॒र्घं स॑चन्ते॒ वरु॑णस्य॒ धाम॑ । अ॒न॒व॒द्यास्त्रिं॒शतं॒ योज॑ना॒न्येकै॑का॒ क्रतुं॒ परि॑ यन्ति स॒द्यः ॥
सदृशीरद्य सदृशीरिदु श्वो दीर्घं सचन्ते वरुणस्य धाम । अनवद्यास्त्रिंशतं योजनान्येकैका क्रतुं परि यन्ति सद्यः ॥
sadṛśīr adya sadṛśīr id u śvo dīrghaṃ sacante varuṇasya dhāma | anavadyās triṃśataṃ yojanāny ekaikā kratum pari yanti sadyaḥ ||

English translation:

“The same today, the same tomorrow, the irreproachable (dawn) precede the distant course of Varuṇa by thirtyyojanas, and each in succession revolves in its (appointed) office.”

Commentary by Sāyaṇa: Ṛgveda-bhāṣya

Varuṇa = sun, the remover of darkness, revolving daily round Mount Meru, the centre of the earth, performing a diurnal circuit of 5,059 yojanas; the dawn being always 30 yojanas in advance of his rising, or first appearance frombehind the mountain in the east,the period called dawn is reckoned from the disappearance of the stars to the appearance of the sun, and is measured, as to the duration, by 21 ghaṭikās and 26 paras. Taking the ghaṭikā at its lowest valuation of half a muhūrta, or 24 minutes, and a para as 1/30th of a ghaṭikā, in a day of 30 ghaṭikās, more than one-third is allotted to the dawn. The sun's daily journey equates to more than 20,000 miles, i.e. the equatorial circumference of the earth. According to the Purāṇas, the sun travels, in a day of 30 muhurtas, or 60 ghaṭikās, 94,500,000 yojanas or 1,575,000 yojanas in one ghaṭikā. One ghaṭikā is assigned to the sandhya, the morning twilight or dawn, and 3 muhurtas or 2 hours 24 minutes, to the Pratar, or early morning (Bently, Hindu Astronomy, p. 185)

Details:

Ṛṣi (sage/seer): dīrghatamasaḥ putraḥ kakṣīvān [dīrghatamasa putra kakṣīvān];
Devatā (deity/subject-matter): uṣāḥ ;
Chandas (meter): nicṛttriṣṭup ;
Svara (tone/note): Swar;

Padapatha [Accents, Plain, Transliterated]:

स॒ऽदृशीः॑ । अ॒द्य । स॒ऽदृशीः॑ । इत् । ऊँ॒ इति॑ । श्वः । दी॒र्घम् । स॒च॒न्ते॒ । वरु॑णस्य । धाम॑ । अ॒न॒व॒द्याः । त्रिं॒शत॑म् । योज॑नानि । एका॑ऽएका । क्रतु॑म् । परि॑ । य॒न्ति॒ । स॒द्यः ॥
सदृशीः । अद्य । सदृशीः । इत् । ऊँ इति । श्वः । दीर्घम् । सचन्ते । वरुणस्य । धाम । अनवद्याः । त्रिंशतम् । योजनानि । एकाएका । क्रतुम् । परि । यन्ति । सद्यः ॥
sa-dṛśīḥ | adya | sa-dṛśīḥ | it | oṃ iti | śvaḥ | dīrgham | sacante | varuṇasya | dhāma | anavadyāḥ | triṃśatam | yojanāni | ekāekā | kratum | pari | yanti | sadyaḥ

Multi-layer Annotation of the Ṛgveda

[Rigveda 1.123.8 English analysis of grammar]