tad-dvÄ«pa-madhye mÄnasottara-nÄmaika evÄrvÄcÄ«na-parÄcÄ«na-vará¹£ayor maryÄdÄcalo 'yuta-yojanocchrÄyÄyÄmo yatra tu catasṛṣu diká¹£u catvÄri purÄṇi loka-pÄlÄnÄm indrÄdÄ«nÄá¹ yad-upariá¹£á¹Ät sÅ«rya-rathasya meruá¹ paribhramataḥ saá¹vatsarÄtmakaá¹ cakraá¹ devÄnÄm aho-rÄtrÄbhyÄá¹ paribhramati
tat-dvÄ«pa-madhye - within that island; mÄnasottara - MÄnasottara; nÄma - named; ekaḥ - one; eva - indeed; arvÄcÄ«na - on this side; parÄcÄ«na - and beyond, or outside; vará¹£ayoḥ - of tracts of land; maryÄdÄ - indicating the boundary; acalaḥ - a great mountain; ayuta - ten thousand; yojana - eight miles; ucchrÄya-ÄyÄmaḥ - whose height and width; yatra - where; tu - but; catasṛṣu - in the four; diká¹£u - directions; catvÄri - four; purÄṇi - cities; loka-pÄlÄnÄm - of the directors of planetary systems; indra-ÄdÄ«nÄm - headed by Indra; yat - of which; upariá¹£á¹Ät - on the top; sÅ«rya-rathasya - of the chariot of the sun-god; merum - Meru Mountain; paribhramataḥ - while circumambulating; saá¹vatsara-Ätmakam - consisting of one saá¹vatsara; cakram - wheel or orbit; devÄnÄm - of the demigods; ahaḥ-rÄtrÄbhyÄm - by the day and night; paribhramati - moves around.
The movement of the sun is confirmed in the Brahma-saá¹hitÄ (5.52): yasyÄjñÄya bhramati saá¹bhá¹›ta-kÄla-cakraḥ. The sun orbits around Mount Sumeru, for six months on the northern side and for six months on the southern. This adds up to the duration of a day and night of the demigods in the upper planetary systems.