The materialistic scientist's endeavor to reach other planets by mechanical vehicles is only a futile attempt. One can, however, reach heavenly planets by virtuous activities, but one can never expect to go beyond Svarga or Janaloka by such mechanical or materialistic activities, either gross or subtle. The transcendentalists who have nothing to do with the gross material body can move anywhere within or beyond the material worlds. Within the material worlds they move in the planetary systems of the Mahar, Janas, Tapas and Satya lokas, and beyond the material worlds they can move in the Vaikunthas as unrestricted spacemen. Narada Muni is one of the examples of such spacemen, and Durvasa Muni is one of such mystics. By the strength of devotional service, austerities, mystic powers and transcendental knowledge, everyone can move like Narada Muni or Durvasa Muni. It is said that Durvasa Muni traveled throughout the entirety of material space and part of spiritual space within one year only. The speed of the transcendentalists can never be attained by the gross or subtle materialists.