Elon Musk has revealed more details of his ambitious plans to establish humanity's first colony on Mars.
In a scientific paper, the SpaceX billionaire says the only way of attracting enough people to build a settlement on the red planet would be to cut the cost of a one-way ticket.
The entrepreneur aims to get the price down of the ticket down to the cost of an average house in the US - or around $200,000 (£157,000), reports Daily Mail.
To achieve this within our lifetime, he will create the first 'Interplanetary Transport System' - a reusable rocket-and-spaceship hybrid powered by 42 SpaceX Raptor engines.
"I want to make Mars seem possible - make it seem as though it is something that we can do in our lifetime," Musk writes in a freely available paper published in New Space.
"There really is a way that anyone could go if they wanted to."
Musk writes that cutting the price of a one-ticket to Mars will be key to starting a viable population on Mars.
"Right now, you cannot go to Mars for infinite money," he says.
"Using traditional methods, taking an Apollo-style approach, an optimistic cost would be about $10 billion (around £8bn) per person."
"You cannot create a self-sustaining civilization if the ticket price is $10 billion per person.
"If we can get the cost of moving to Mars to be roughly equivalent to a median house price in the United States, which is around $200,000 (£157,000), then I think the probability of establishing a self-sustaining civilization is very high.
"I think it would almost certainly occur."
He adds that "not everyone would want to go" but people from all walks of life could apply for sponsorship in order to take up much-needed labour positions on the colony.
Key to cutting the price of space travel is to build a high-power reusable rocket-and-spaceship hybrid, he says.
Elon Musk's plan for mars
1. Cut the price of space travel
2. Build a reusable 'interplanetary trave system'
3. Establish spaceship fuel stations on Mars
4. Explore the Solar system
"You could use any form of transport as an example of the difference between reusability and expendability in aircraft," he writes.
"A car, bicycle, horse, if they were single-use-almost no one would use them; it would be too expensive.
"However, with frequent flights, you can take an aircraft that costs $90 million (£71m) and buy a ticket on Southwest right now from Los Angeles to Vegas for $43, including taxes.
"If it were single use, it would cost $500,000 (£392,000) per flight. Right there, you can see an improvement of four orders of magnitude."
He writes that both the booster and spaceship will be propelled by SpaceX's Raptor engine, which the company is still developing.
Musk says the engines will be three times stronger than the engines that power his Falcon 9 rocket.
The booster will be powered by 42 Raptor engines, which will make it the most powerful rocket in humanity's history by a long way.
It will be able to launch 300 metric tonnes to low Earth orbit. In comparison, Nasa's record-breaking Saturn V moon rocket is capable of 135 metric tonnes.
The rocket could get one million people to Mars within 50 to 100 years, he says.
He added that key to building an all-powerful reusable rocket is establishing a way to produce fuel on Mars.
"Producing propellant on Mars is obviously also very important. Again, if we did not do this, it would have at least a half order of magnitude increase in the cost of a trip," he writes.
"It would be pretty absurd to try to build a city on Mars if your spaceships just stayed on Mars and did not go back to Earth.
"You would have a massive graveyard of ships; you have to do something with them."
Musk hopes to realise these goals within his lifetime and added that his spaceship could be used to go "beyond Mars".
He says: "There is obviously the rocket booster, the spaceship, the tanker and the propellant plant, and the in situ propellant production.
"If you have all four of these elements, you can go anywhere in the solar system by planet hopping or moon hopping.
"By establishing a propellant depot on the asteroid belt or on one of the moons of Jupiter, you can make flights from Mars to Jupiter.
"In fact, even without a propellant depot at Mars, you can do a flyby of Jupiter."
Why did Musk choose Mars?
Musk says that SpaceX will target Mars for colonisation over other planets in the solar system as it is the most similar to Earth.
He writes: "Sometimes people wonder, 'Well, what about other places in the solar system? Why Mars?'"
"We have, in terms of nearby options, Venus, but Venus is a high-pressure-super-high-pressure-hot acid bath, so that would be a tricky one.
"Venus is not at all like the goddess. So, it would be really difficult to make things work on Venus.
"Then, there is Mercury, but that is way too close to the sun. We could potentially go onto one of the moons of Jupiter or Saturn, but those are quite far out, much further from the sun, and much harder to get to.
"It really only leaves us with one option if we want to become a multi-planetary civilization, and that is Mars."
Characteristics of Earth and Mars
• Diameter 12,756km/7,926 miles
• Average distance from sun150,000,000km/93,000,000 miles
• Temperature range -88°C to 58°C/-126°F to 138°F
• Atmospheric composition 78% N2, 21% O2, 1% other
• Gravity (weight) 100lbs
• Day Length 24 hours
• Land mass 148.9 million km sq
• People 7 billion
• Diameter 6,792km/4,220 miles
• Average distance from sun 229,000,000km/142,000,000 miles
• Temperature range -140°C to 30°C/ -285°F to 88°F
• Atmospheric composition 96% CO2, <2% Ar, <2% N2, <1% other
• Gravity (weight) 38lbs (62.5% less gravity)
• Day Length 24 hours 40 minutes
• Land mass 144.8 million km sq (97% of Earth)
• People 0
Data Source: Elon Musk