This Vidura was Yamarāja. So he was cursed by one muni to go down and take birth in śūdra family. Yamarāja was very exalted post, but still... Yamarāja means the superintendent of death. There is Pitṛloka, Yamaloka, different planets. And where each planet is situated, how many miles, yojana... The Sanskrit is called yojana. Yojana means eight miles. So how many yojana is one planet situated from another planet, that is all described in the Bhāgavata, Fifth Canto.
So there is a Pitṛloka, Yamaloka. Just like the moon planet, we are trying to go there, but there are different lokas, planets, and you can go, not by the sputnik, by force. No. You'll have to qualify yourself. Just like to come to your country, to take the permanent visa, I had to qualify in so many ways, the immigration department, not by force. Even in this planet, you cannot enter any country without being permitted. How you can enter other planets? Simply by force? No, that is not possible. You have to qualify yourself. That is stated in the Bhagavad-gītā. Yānti deva-vratā devān (BG 9.25). A person can go to the planets of the demigods, devān. There are many demigods: Indra, Candra, Varuṇa, Vāyu. Brahmaloka, Prajāpatiloka, Siddhaloka—they are in the higher planetary systems. This is... We are now situated in the middle, Bhūrloka. It is called Bhūrloka. Above this, there is Bhuvarloka. Above that, Svarloka, Janaloka, Maharloka, Satyaloka, like that, ūrdhvaloka. They are higher planetary... Then middle. And then lower planetary system. Ūrdhvaṁ gacchanti sattva-sthāḥ. If you develop sattva-guṇa, the quality of goodness, then according to your degree of goodness, you get promoted to the higher planets. Ūrdhvaṁ gacchanti sattva-sthā madhye tiṣṭhanti rājasāḥ (BG 14.18). If you are in the passion modes, then you stay here in this middle planetary system. And jaghanya-guṇa-vṛtti-sthā adho gacchanti tāmasāḥ. Those who are in the most abominable condition of life, adho gacchanti, they go down. Not only the down planetary system, but even to the animal kingdom, the beasts, birds, trees, plants, aquatics. You have to go.