SB 3.16.27

brahmovāca
atha te munayo dṛṣṭvā
 nayanānanda-bhājanam
vaikuṇṭhaṁ tad-adhiṣṭhānaṁ
 vikuṇṭhaṁ ca svayaṁ-prabham
Word for word: 
brahmā uvāca — Lord Brahmā said; atha — now; te — those; munayaḥ — sages; dṛṣṭvā — after seeing; nayana — of the eyes; ānanda — pleasure; bhājanam — producing; vaikuṇṭham — the Vaikuṇṭha planet; tat — of Him; adhiṣṭhānam — the abode; vikuṇṭham — the Supreme Personality of Godhead; ca — and; svayam-prabham — self-illuminating.
Translation: 
Lord Brahmā said: After seeing the Lord of Vaikuṇṭha, the Supreme Personality of Godhead, in the self-illuminated Vaikuṇṭha planet, the sages left that transcendental abode.
Purport: 

The transcendental abode of the Supreme Personality of Godhead, as stated in Bhagavad-gītā and confirmed in this verse, is self-illuminated. In Bhagavad-gītā it is said that in the spiritual world there is no need of sun, moon or electricity. This indicates that all the planets there are self-illuminated, self-sufficient and independent; everything there is complete. Lord Kṛṣṇa says that once one goes to that Vaikuṇṭha planet, he never returns. The inhabitants of Vaikuṇṭha never return to the material world, but the incident of Jaya and Vijaya was a different case. They came to the material world for some time, and then they returned to Vaikuṇṭha.