Editor's Note: This article was originally published on 28 September, 2016. We are republishing the article as Elon Musk has presented a study on making Human Life Interplanetary in the Journal New Space.
Elon Musk has unveiled plans that will let anyone who wants to go to Mars buy a ticket for about the cost of a home. The schedule is tight, there are few launch windows, and things have to proceed like clockwork if this is to happen. Humans going to Mars is not about a symbolic display of technological progress, or a mission of scientific research. This is a question of the survival of the species. Humans cannot stay on Earth indefinitely, as that would eventually lead to an extinction event.
The SpaceX plans charts a course where the cost of going to Mars is reduced considerably. Right now, there is no real way for humans to go to Mars. Using traditional methods, the cost of a ticket can be reduced to about $10 billion per person, which is still too much for most people. The idea is to use innovative methods to significantly reduce the cost of the mission. That means reducing the cost of travelling to Mars by five million per cent.
The major portion of the cost will be saved by reusing the spaceship that will take people to mars. The capacity for the colonial ship has to be 100 people, or more for the plan to be feasible. There were even plans of packing in 200 people onto a ship, so it could get crowded on the journey to Mars. There are solar panels mounted on retractable fins on the ships, which will be used for power on the journey to Mars. The colonial ship will be equipped with the new raptor engines, and pushed into orbit on a booster rocket. The ship along with the booster is one of the largest launch vehicles till date, with a gross lift-off mass of 10,500 tons.
The only comparable rocket is the Saturn V with a gross lift-off mass of 3,039 tons. The vehicle is 122 meters in height with a diameter of 12 meters. Musk wants to build even bigger vehicles with more capacity. The main reason for this is that there are very few launch windows, and the more people and cargo that can be loaded on board in each mission to mars, the cheaper it becomes per ton to ship it.
The booster rocket is also equipped with raptor engines, and is meant to be reusable. The booster will take the spaceship to Earth orbit, where it will be parked while the booster returns to the ground with a vertical landing. Then, a fuelling tank is loaded onto the booster, and it takes off again. The fuelling tank fuels the colonial ship in Earth orbit. This will reduce the cost of repeatedly launching the ship into space. The Ship then travels to Mars, lands, takes off and comes back to Earth.
The first ship will have a propellant plant, which will be further expanded over subsequent ships. This plant is meant to harvest the propellant needed for spaceflight on Mars itself. Mars has a large amount of water ice on the surface, and carbon dioxide in the atmosphere. These natural resources will be harvested, and chemically transformed into a methane and oxygen based propellant. This propellant has many desirable properties, including how well it can be transferred between crafts, how cheap it is, the feasibility of being produced on Mars and support for large vehicle sizes.
The design of the whole system means that the cost of a taking a person to Mars will be less than $200,000 and eventually less than $100,000. Elon Musk plans to reroute the earnings from satellite launches, and missions that take astronauts to the International Space Station, into the Mars colonisation mission. Elon Musk said that the main reason he is accumulating assets is to do everything he can possibly do to make human life multi-planetary, a statement that received an ovation. As people start believing this is possible, Musk believes that the support in the form of funding will snowball.
There will be Red Dragon missions to mars. There are pilot spacecraft that will survey Mars for the colonisation mission. This will include finding locations where carbon dioxide can be collected and water can be mined. Potential landing sites for the colonial ships will be identified, along with any hazards that may exist on the surface. A Dragon 2 mission will be sent on 2018, and another one in 2020. Musk wants to send a flight on every launch window to Mars, similar to a scheduled train time table, where there is always a train waiting. The Dragon 2 is designed to be a propulsive lander, the kind of spaceship that can hop between planets and land on any surface.
A permanent human settlement on Mars would start with a sustainable city, an ecosystem within itself. One of the key problem areas is providing power to the city, which could be done through an array of solar panels. A healthy self sustaining population is a minimum of 1,000,000 people. To get 1,000,000 people on would require between 5000-10,000 missions, with at least 100 people on board each ship.
SpaceX ambitions does not stop at Mars though. The Mars Colonial Transporter was recently renamed as the Interplanetary Transport System. Attractive targets are moons of the gas giants Saturn and Jupiter, that are known to have subsurface oceans. A day before Musk gave his presentation on plans to colonise Mars, NASA announced that the Hubble space telescope had found evidence of plumes of water on Europa. Establishing permanent human settlements in these resource rich moons could provide a base for commercial and scientific activities in the outer solar system, including asteroid mining.