Engineering news
Elon Musk, chief executive of private US aerospace company SpaceX, has outlined his plans to colonise Mars.
Speaking at the annual International Astronautical Congress in Guadalajara, Mexico, he addressed the technical details of the mission to create a self-sustaining city on the red planet.
Musk said: “What we really want to achieve is to make Mars seem possible…something we can do in our lifetimes. And is there a way that anyone can go if they wanted to.”
Musk demonstrated a simulation of the Interplanetary Transport System (ITS) that consisted of a booster and a spaceship. The primary structure is constructed from carbon fibre, is 122m high and 17m wide, with a densified CH4/O2 propellant.
The booster will be equipped with a total of 42 Raptor engines: 21 in the outer ring, 14 in the inner ring, and seven in the centre cluster. While the outer engines will be fixed in place, the centre engines will have gimbals. The spaceship will be equipped with nine Raptor engines. Musk stated that this configuration of the engines will ensure the mission continues safely even in the event of multiple engine losses.
Methane is Musk’s choice of fuel as it is easy to produce on Mars and does not require insulation and cryogenic cooling as liquid hydrogen would. The spaceship will be kept lightweight by having its tank empty at lift-off and fuelling it mid-orbit. Once the spaceship and booster separate during the mission, the booster will return to the launch mount to pick up a propellant and bring it back to the spaceship to provide fuel. This will make the mission cheaper by 500%, according to Musk.
The ITS will lift off with a 127,800kN thrust, travelling at 6km/s for a trip that will take 80 days to arrive at Mars. Musk is aiming to reduce the travel time in the distant future to 30 days. Solar arrays on the spaceship will be deployed during the mission with 200kW of power.
The first test flight will take place in four years and civilian trips will commence in 10 years, said Musk. The spaceship can accommodate up to 100 people and carry 408 tonnes of cargo. The current mission cost per person stands at $10 billion, but Musk is planning to reduce that to $200,000 per person by ensuring the transportation system is reusable.
Musk estimates that it will take colonies of at least 1 million people and 40 to 100 years to achieve a fully self-sustaining civilisation on Mars. To make migration more appealing, Musk assured that the spaceship will keep passengers entertained with zero-gravity games, films and restaurants.
However, Musk does not want to limit the ITS to Mars. He says there is potential to go beyond as long as you have four elements: a rocket booster, a space ship, a tanker, and a propellant plant. These would make planet hopping or moon hopping a possibility, according to Musk.
The first firing test of the Raptor engine that took place a day before the presentation was successful. The rocket has a thrust of 3MN at 300 bar with a specific impulse of 382 seconds. Its chamber pressure is almost three times that of SpaceX’s Merlin engines that are used on its Falcon 9 rockets.
Earlier in the year, the Falcon 9 exploded about two minutes after take-off from Cape Canaveral.