SB 10.1.1

śrī-rājovāca
kathito vaṁśa-vistāro
 bhavatā soma-sūryayoḥ
rājñāṁ cobhaya-vaṁśyānāṁ
 caritaṁ paramādbhutam
Synonyms: 
śrī-rājā uvāca — King Parīkṣit said; kathitaḥ — has already been described; vaṁśa-vistāraḥ — a broad description of the dynasties; bhavatā — by Your Lordship; soma-sūryayoḥ — of the moon-god and the sun-god; rājñām — of the kings; ca — and; ubhaya — both; vaṁśyānām — of the members of the dynasties; caritam — the character; parama — exalted; adbhutam — and wonderful.
Translation: 
King Parīkṣit said: My dear lord, you have elaborately described the dynasties of both the moon-god and the sun-god, with the exalted and wonderful character of their kings.
Purport: 

At the end of the Ninth Canto, Twenty-fourth Chapter, Śukadeva Gosvāmī summarized the activities of Kṛṣṇa. He spoke of how Kṛṣṇa had personally appeared to reduce the burden on the earth, how He had manifested His pastimes as a householder, and how, soon after His birth, He had transferred Himself to His Vrajabhūmi-līlā. Parīkṣit Mahārāja, being naturally a devotee of Kṛṣṇa, wanted to hear more about Lord Kṛṣṇa. Therefore, to encourage Śukadeva Gosvāmī to continue speaking about Kṛṣṇa and give further details, he thanked Śukadeva Gosvāmī for having described the activities of Kṛṣṇa in brief. Śukadeva Gosvāmī had said:

jāto gataḥ pitṛ-gṛhād vrajam edhitārtho
 hatvā ripūn suta-śatāni kṛtorudāraḥ
utpādya teṣu puruṣaḥ kratubhiḥ samīje
 ātmānam ātma-nigamaṁ prathayañ janeṣu

“The Supreme Personality of Godhead, Śrī Kṛṣṇa, known as līlā-puruṣottama, appeared as the son of Vasudeva but immediately left His father’s home and went to Vṛndāvana to expand His loving relationships with His confidential devotees. In Vṛndāvana the Lord killed many demons, and afterward He returned to Dvārakā, where according to Vedic principles He married many wives who were the best of women, begot through them hundreds of sons, and performed sacrifices for His own worship to establish the principles of householder life.” (Bhāg. 9.24.66)

The Yadu dynasty belonged to the family descending from Soma, the moon-god. Although the planetary systems are so arranged that the sun comes first, before the moon, Parīkṣit Mahārāja gave more respect to the dynasty of the moon-god, the soma-vaṁśa, because in the Yādava dynasty, descending from the moon, Kṛṣṇa had appeared. There are two different kṣatriya families of the royal order, one descending from the king of the moon planet and the other descending from the king of the sun. When the Supreme Personality of Godhead appears, He generally appears in a kṣatriya family because He comes to establish religious principles and the life of righteousness. According to the Vedic system, the kṣatriya family is the protector of the human race. When the Supreme Personality of Godhead appeared as Lord Rāmacandra, He appeared in the sūrya-vaṁśa, the family descending from the sun-god, and when He appeared as Lord Kṛṣṇa, He did so in the Yadu dynasty, or yadu-vaṁśa, whose descent was from the moon-god. In the Ninth Canto, Twenty-fourth Chapter, of Śrīmad-Bhāgavatam, there is a long list of the kings of the yadu-vaṁśa. All the kings in both the soma-vaṁśa and sūrya-vaṁśa were great and powerful, and Mahārāja Parīkṣit praised them very highly (rājñāṁ cobhaya-vaṁśyānāṁ caritaṁ paramādbhutam). Nonetheless, he wanted to hear more about the soma-vaṁśa because that was the dynasty in which Kṛṣṇa had appeared.

The supreme abode of the Personality of Godhead, Kṛṣṇa, is described in Brahma-saṁhitā as the abode of cintāmaṇi: cintāmaṇi-prakara-sadmasu kalpa-vṛkṣa-lakṣāvṛteṣu surabhīr abhipālayantam. The Vṛndāvana-dhāma on this earth is a replica of that same abode. As stated in Bhagavad-gītā (8.20), in the spiritual sky there is another, eternal nature, transcendental to manifested and unmanifested matter. The manifested world can be seen in the form of many stars and planets such as the sun and moon, but beyond this is the unmanifested, which is imperceptible to those who are embodied. And beyond this unmanifested matter is the spiritual kingdom, which is described in Bhagavad-gītā as supreme and eternal. That kingdom is never annihilated. Although material nature is subject to repeated creation and annihilation, that spiritual nature remains as it is eternally. In the Tenth Canto of Śrīmad-Bhāgavatam, that spiritual nature, the spiritual world, is described as Vṛndāvana, Goloka Vṛndāvana or Vraja-dhāma. The elaborate description of the above-mentioned śloka from the Ninth Canto — jāto gataḥ pitṛ-gṛhād (Bhāg. 9.24.66) — will be found here, in the Tenth Canto.