Srimad-Bhagavatam: Canto 5 - Chapter 1 - Verse 17
Sanskrit:
तत उत्तरस्मादृषय एकादशलक्षयोजनान्तर उपलभ्यन्ते य एव लोकानां शमनुभावयन्तो भगवतो विष्णोर्यत्परमं पदं प्रदक्षिणं प्रक्रमन्ति ॥ १७ ॥
ITRANS:
tata uttarasmād ṛṣaya ekādaśa-lakṣa-yojanāntara upalabhyante ya eva lokānāṁ śam anubhāvayanto bhagavato viṣṇor yat paramaṁ padaṁ pradakṣiṇaṁ prakramanti.
Translation:
Situated 8,800,000 miles above Saturn, or 20,800,000 miles above earth, are the seven saintly sages, who are always thinking of the well-being of the inhabitants of the universe. They circumambulate the supreme abode of Lord Viṣṇu, known as Dhruvaloka, the polestar.
Purport:
Śrīla Madhvācārya quotes the following verse from the Brahmāṇḍa Purāṇa: “Lord Viṣṇu, who is the source of knowledge and transcendental bliss, has assumed the form of Śiśumāra in the seventh heaven, which is situated in the topmost level of the universe. All the other planets, beginning with the sun, exist under the shelter of this Śiśumāra planetary system.”