so ’tivrajya munīn api
parastād yad dhruva-gatir
viṣṇoḥ padam athābhyagāt
tri-lokīm—the three planetary systems; deva-yānena—by the transcendental airplane; saḥ—Dhruva; ativrajya—having surpassed; munīn—great sages; api—even; parastāt—beyond; yat—which; dhruva-gatiḥ—Dhruva, who attained permanent life; viṣṇoḥ—of Lord Viṣṇu; padam—abode; atha—then; abhyagāt—achieved.
Dhruva Mahārāja thus surpassed the seven planetary systems of the great sages who are known as saptarṣi. Beyond that region, he achieved the transcendental situation of permanent life in the planet where Lord Viṣṇu lives.
The airplane was piloted by the two chief associates of Lord Viṣṇu, namely Sunanda and Nanda. Only such spiritual astronauts can pilot their airplane beyond the seven planets and arrive in the region of eternal blissful life. It is confirmed in the Bhagavad-gītā also (paras tasmāt tu bhāvo ’nyaḥ [Bg. 8.20]) that beyond this planetary system begins the spiritual sky, where everything is permanent and blissful. The planets there are known as Viṣṇuloka or Vaikuṇṭhaloka. Only there can one get an eternal blissful life of knowledge. Below Vaikuṇṭhaloka is the material universe, where Lord Brahmā and others in Brahmaloka can live until the annihilation of this universe; but that life is not permanent. That is also confirmed in the Bhagavad-gītā (ābrahma-bhuvanāl lokāḥ). Even if one goes to the topmost planet, one cannot achieve eternal life. Only by arriving in Vaikuṇṭhaloka can one live an eternally blissful life.
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