Elon Musk, an American billionaire and co-founder of SpaceX, announced development of a rocket motor designed for flight to Mars. According to his calculations, the price of "delivery" of a single colonist to the Red Planet would be half a million dollars. The future "Martians" are expected to pay the entire cost of the trip.
"The ticket price should be low enough so that most people in developed countries by the age of 45 or so could save money for a flight," Musk proclaimed at a conference at the Royal Society of Astronautics (UK). He added that $500,000 would buy a house in California.
Meanwhile, statistics show that most Americans are not able to save this amount by the age of 45. Moreover, the average real income of American households has not increased since 1975. It is unlikely that even in developed countries there will be a large number of people willing to colonize Mars. The average age is not the best for becoming a "cosmonaut." At the age of 45 it is not easy to travel to space and then adapt to far from comfortable conditions of another planet.
However, Musk has his own ideas in this regard. Let's say at the beginning of the colonization only one in 100,000 humans will be ready to pay for a ticket to Mars. Most likely, by the time the world's population will grow to about 8 billion people. Therefore, we would have as many as 80 thousand potential colonists who would purchase tickets for a total of $40 billion. This is enough to create the first colony on Mars the size of a small city on Earth. Primary infrastructure will have to be prepared, but it would require less money than the transfer of humans to Mars.
It is the delivery of colonists to Mars that is by far the most challenging task. Even a heavy rocket carrier Falcon-9 with a built-in first stage will not be able to complete such an operation. Now SpaceX is developing a space vehicle called MCT (according to various sources, it stands for Mass Cargo Transport, or Mars Colony Transport). This ship is assumed to run on closed cycle methane engine.
Unlike in Falcon-9, in the engines used in the new vehicle gas will not be released into the environment, but will get into the combustion chamber, thereby increasing traction and engine efficiency. Moreover, methane is much cheaper, for example, than hydrogen, which is important for frequent flights. It can be safely stored at high temperatures, whereas under these conditions liquid hydrogen makes the tanks material more brittle.
But most importantly, methane does not have to be delivered from Earth. It can be obtained directly on Mars using terrestrial anaerobic bacteria and local substrates. Theoretically, hydrogen can be produced on Mars as well, but since this is only possible by electrolysis of water that is found on Mars under the sand in the form of ice, the process would be much more complex and energy-intensive.
Incidentally, according to Elon Musk, using a "reusable" ship for flights that would return to Earth in the early stages of colonization is not feasible, since the distance between the Earth and Mars is constantly changing. The first ship will not transfer many people. Mostly its compartments will be occupied by construction material for the pressurized dome under which the colonists would live, as well as plants and fertilizer. It is also expected to send to Mars supplies of oxygen and water. Water will also provide protection from radiation, which is higher on the Red Planet than on Earth.
Generally, the idea is feasible. It would be possible to find 80,000 people who would agree to be pioneers on an alien planet. Some will look for exotic and romantic adventures, others would look for a chance to leave the overcrowded earth or escape from their terrestrial problems. Another question is whether these people will be fit for Mars exploration? There will be a need not only in people who know how to make money, but also a variety of scientific and technical experts, teachers, doctors, psychologists, and even laborers.
To meet the need in various professionals, a cheap way of transporting them will be required, and then a "ticket" to Mars cannot cost half a million. As for a handful of millionaires, it is unlikely that they can make substantial contributions. So far, none of wealthy people are in a hurry to invest in this expensive project.