SpaceX CEO and billionaire Elon Musk revealed further details about his plans to build a self-sustaining city on Mars. His plans were recently published in the journal New Space.

According to Musk, he is consistently refining his plans. Earlier, his speech called "Making Humans a Multi-planetary Species" enumerated his initial plans to make his ambitious journey to Mars possible. He said that humans must work to build a colonization outside the Earth.

The paper discussed why Musk chose Mars and how his plans will progress from early explorations to building a self-sustaining city on the red planet. He also emphasized that he wanted to "make Mars possible." Musk believes that if the human race remains confined on the planet there will be an extinction eventually, so the only way to save the population from that is to build another colonization on Mars.

In order to become a full-pledged multi-planetary species, mankind should be able to build, not just a colony, but a self-sustaining city on Mars that will eventually become a habitable planet with the help of technology.

But why Mars? This is because the scientific community is well aware that there is a limited choice when it comes to potential planets for exploration within the Solar System. Earth's neighbor like Mercury and Venus are almost impossible to work with. This led his work to focus on Mars - the only choice man has to become a multi-planetary species.

"It would be quite fun to be on Mars because you would have gravity that is about 37% of that of Earth, so you would be able to lift heavy things and bound around," SpaceX CEO Elon Musk wrote on the paper. "Furthermore, the day is remarkably close to that of Earth."

Musk says all the data about the red planet, previously gathered by NASA will help in building the self-sustaining city on Mars.