It has been nearly half a century since humans have last stepped foot on another celestial body. American astronaut Eugene Cernan’s final steps on the Moon in 1972 have been a poignant reminder of the absence of regular manned-space travel. Not since NASA’s Project Apollo in the late 1960s, when American astronauts travelled nine times to the moon and nine years, have humans ventured out past the great unknown of space to foreign lands.
The desire to colonise the Moon waned during the ‘Space Race’ between the USA and USSR, amidst the Cold War. Scientists on both sides quickly became aware that the landscape of the Moon was not viable for extra-terrestrial living following the use of planetary analogs. These are habitats on Earth that are designed to replicate the surface of celestial bodies to allow humans to test the adaptability of modern technology in an experimental setting. Attention soon turned to Mars, but every attempt since 1960 has failed to land humans on the Red Planet.
“To live on Mars is not going to be easy. Mars has a hostile environment. Living on Mars is no better than living on the South Pole or the tip of Mount Everest.”
Lord Martin Rees, Britain’s Chief Astrophysicist and Astronomer Royal since 1995.
Our Next Frontier, 140-Million-Miles Away
It’s the 29th of September 2017 and SpaceX CEO, Elon Musk, takes the stage at the 68th International Astronautical Congress in Adelaide, Australia. The usually fervent atmosphere of an audience of industry leaders, former astronauts and space enthusiasts dissipates as Musk publicly confirms his company’s intention to commit to interplanetary travel.
“You want to wake up in the morning and think the future is going to be great – and that’s what being a spacefaring civilization is all about. It’s about believing in the future and thinking that the future will be better than the past. And I can’t think of anything more exciting than going out there and being among the stars.”
Elon Musk, speaking on a panel at the 68th International Astronautical Congress in 2017.
Musk’s vision, however, is not without many perilous dangers. The Martian atmosphere is mainly composed of carbon dioxide, nitrogen and argon. This means that plants cannot functionally grow on Mars without compressing the atmosphere. As a result, any initial food supplies to astronauts on Mars will need to make the journey through deep space and humans would find it near impossible to naturally terraform the Martian atmosphere to model that of Earth. Before addressing the problem of surviving on Mars, however, SpaceX will need to solve the issue of building a rocket powerful enough to make the 140-million-mile mission in the first place.
The Most Powerful Launch Vehicle Ever Developed
It wouldn’t be remiss to term SpaceX’s ‘Starship’ a revolution in spacefaring and aerospace engineering. At just 160 feet tall from nose to foot, the rocket will house all the necessary modules for a trip to Mars including the crew, life-support and cargo for each mission. Despite this relatively small size (NASA’s Apollo 11 rocket was 363 feet), the Starship is capable of carrying over 100+ Tons to Earth’s orbit.
Another feat of innovation that has become synonymous with SpaceX’s mission is the concept of renewability. Musk has been committed to reusing both the Starship and the 230 foot ‘Super Heavy’ rocket boosters used in propelling the Starship into Earth’s orbit. To date, SpaceX has conducted 15 missions on Earth testing the capabilities of revised versions of the Starship. The potential of these vehicles is not to be underestimated, for instance the Super Heavy Booster (which is set for a redesign in the coming months), can reach 17 million pounds of thrust compared to the 7.6 million pounds achieved by NASA’s most powerful rocket, the Saturn V. Also crucial for missions to Mars is how the Boosters achieve a thrust-to-weight ratio of 1.5 lbs/Tonne. Vehicles like the Starship and Booster that rely on vertical take-off need to have greater thrust than weight to provide the acceleration needed to push past Earth’s gravity.
Really the ad for going to Mars would be like Shakleton’s ad for going to the Antarctic. There’s a good chance of death, going in a little can through deep space. [If] you land successfully, … there’s a good chance you’ll die there. We think you can come back; but we’re not sure.”
Elon Musk, speaking at the 69th International Astronautical Congress in 2018.
If both the Starship and the Super-Heavy Booster make up the crown in SpaceX’s rocket arsenal, then the Raptor engines powering them are the jewels. These take on two variants, the sea-level engine which provides 200 Tons of thrust and make up half of the 6 Starship engines, and the vacuum (R-Vac) variant providing the remaining 3 engines. The R-Vac features state-of-the-art engineering including regenerative cooling, where methane is pumped via milled copper channels with an accompanying Inconel jacket to cool the walls of the engine, as it travels through deep space.
A recent development to the rocket engines has been the introduction of the Raptor 2 engine for the sea-level variants. This engine will increase thrust capacity to 230 Tons and improve the capability of the Super Heavy Booster to utilise up to 30 spare Raptor engines if needed throughout the mission.
How We’re Going To Get There
- Stage 1 – Starship launches, powered by three SpaceX Raptor engines. Each engine shuts down sequentially until the Starship reaches apogee in orbit. The accompanying Super Heavy booster rocket then detaches and returns to Earth.
- Stage 2 – Starship docks with strategically aligned ‘tanker’ vehicles in an “on orbit” propellant transition process. These are Starships stripped of weight and cargo and repurposed as fueling stations for propellant. The added fuel is essential to transporting all 100+ Tonnes of cargo to Mars at a low cost. This is because long-duration beyond Earth orbit (BEO) is only environmentally viable if the cost per ton delivery to Mars is reduced. The Starship then reorientates to align with the flight path to Mars.
- Stage 3 – Starship, now refilled, begins the 6-month journey to Mars. SpaceX scientists monitor the progress of the rocket remotely from Earth.
- Stage 4 – Starship enters Mars’ atmosphere for entry at a speed of 7.5 km/s. It begins to decelerate to minimise ablation (the vaporisation or erosion that occurs during flight) to the heat shield as it aerodynamically descends. The four landing flaps begin to actuate to control altitude and place the landing; controlled by an automated onboard flight computer.
- Stage 5 – Starship lands on the Martian surface in an upright position. Any rovers within sight of the landing observe the three Raptor engines reigniting to enable a landing flip manoeuvre before touching down.
“One can argue that it’s an effective strategy, and it is less important that the timeline be accurate than it is for it to be inspirational.”
Steve Nutt, Professor of Material Science and Aerospace Engineering at the University of Southern California.
An Optimist’s Timeline of Mars Colonisation
27/04/25 – A Rough Landing
Five uncrewed cargo Starships land together on Erebus Montes, Mars to deliver life-support systems. Included in these systems are backup fuel, liquid oxygen and water, dried food, waste management systems, spacesuits, medical supplies, habitation pods and experiment equipment. They also carry solar panels to power the future base and fuel production. Although solar panels are only 43% as efficient on Mars as they are on Earth, the Starships carry 7 football fields worth of solar arrays to the Martian surface. Before landing, one of the five Starships – nicknamed ‘Heart of Gold’ – deploys the Starlink Global Communications Network in orbit: four satellites join the current 14 orbiting Mars.
The parked Starships begin to release rovers and BostonDynamics robot dogs to deploy the solar arrays, and prepares fuel production experiments by drilling icy water deposits. By using the Sabatier process (using catalysts to generate an exothermic reaction), CO2 from the atmosphere is combined with hydrogen from mined water to produce water, oxygen and methane. In order to refuel the Starships completely, Martian water needs to be mined and filtered of impurities at a rate of 1 ton a day. Roughly 17 megawatt hours of solar power is needed to mine 1 ton of water per metric ton of liquid oxygen and methane propellant produced.
On the surface, Mars Base ‘Alpha’ is established at a location of less than 40 degrees latitude (for optimal solar power production), in a warm average temperature and as close as possible to large subsurface water ice deposits. Elsewhere, multi-use rovers begin to prepare the Martian regolith (loose soil) by flattening and melting it to form a large, flat landing pad for future Starships.
20/06/27 – The First Red Footsteps
Two more Starships land on Mars with the mission to ‘make life sustainable and interplanetary’. These ships carry a 30-strong crew including scientists, engineers, medical specialists and military personnel with scientific backgrounds. Each of these ground-breakers are committed to their 2 years and 2 months of Martian residence.
Ten more cargo Starships also land carrying over-supplies of life-support for this crew. Before beginning any work, the astronauts spend their first week confined to the Starships; acclimating to Martian gravity (38% of Earth’s) by physically exercising to rebuild muscle wastage over the 6-month journey. During this time the Starlink Communications Network is utilised to monitor the surface temperature (averaging minus 63 degrees Celsius) and wind speed. Orbiter satellites operate as extra-terrestrial weather stations to monitor seismic waves below the Martian surface to warn astronauts of incoming quakes.
A week later, the life support systems are deployed on the surface. Astronauts take their first steps on Martian ground and use ‘In Situ Resource Utilisation (ISRU) for deep cryogenic fuel production (supercooled liquid methane and oxygen or LOX). This is part of NASA-developed proprietary technology to promote sustainable infrastructure projects in space exploration missions. Experiments also begin to turn Martian soil into a 3D printable material; taking advantage of its inherent resistance to surface erosion and radiation. At the same time, ‘The Green Project’ begins work to cultivate Martian soil for genetically engineered plants from Earth to be planted including rye, radishes, tomatoes, beans, carrots and potatoes. Astronauts also experiment with cyanobacteria to modify nitrogen in the atmosphere into ammonia fertiliser for human waste-recycled compost.
11/07/29 – Terraforming Terra Nullius
On Earth, SpaceX gigafactories are producing two Starships a week at only $5 million each. At this rate, by the time of the next launch window (every 2 years and 2 months, when Mars and Earth are the closest distance apart), 217 Starships – each with separate crews – will be ready to make the voyage. The window can sometimes, however, be limited to just 12 days, with only a few hours to successfully launch from Earth.
Across the galaxy, the 30 original astronauts leave Mars in a single Starship to return to Earth whilst 76 more humans land to construct permanent greenhouse domes for further crop production. Amongst these are architects, scientists, at least four privately paying individuals (each paying $50 million), engineers and botanist farmers. By this time, enough food has been cultivated by The Green Project to produce whole Martian-grown meals for the new inhabitants. This reduces the demand for frozen and dried food to be sent from Earth in future resupply missions. Construction immediately begins on DepotX, a dedicated refuelling station on Mars, and an AI “Spacefactory” 3D printer starts producing habitats using Martian soil material. Once made, a Starship is strategically disassembled to create the communications and life-support systems required for these habitats.
In the next two months, the human population increases to 354, as new Starships arrive with more sophisticated 3D printing robots and larger “hydroponic” crop facilities are built. As the majority of food consumption switches over to fresh Martian produce, restaurateur and Elon’s brother, Kimble Musk sets up a series of vertical food cultivators called “Martian Farms”. Elsewhere, other astronauts test locations for underground habitat settlement with data being sent to and evaluated by BoringCompany on Earth. Fish from Earth are sent to Mars to make an Aquaponic greenhouse from Martian water production. Before long, Jeff Bezos’ Blue Origin Programme officially registers the domain name “amazon.mars”.
Meanwhile, in low Earth orbit, the largest fleet of Starships ever assembled is ready and waiting for the greenlight for a rare launch window opportunity.
17/11/35 – The Great Crossing
The year 2035 is unique for interplanetary travel, a “perihelic opposition” is in session with the shortest possible window (5 months) for the voyage to Mars from Earth. The Mars population subsequently increases to 748 as settlers take advantage of this. 3D printing on Mars is now fully automated and is used for expanding Base Alpha into a town-sized settlement with underground interconnected domes and even a Martian hospital.
In the next five years, the human population rises to 1579 and then doubles to 3331 as settlers intending to permanently relocate to Mars arrive. Heavy machinery is also introduced, with the BoringCompany drill beginning to modify cave systems for underground habitat development. Robotic bases, operating as mining outposts, are set up at further and further distances from Base Alpha. Simultaneously, nation states from Earth construct smaller habitats as embassies. By this time at least one natural death and birth would have occurred on Mars, with scientists still closely monitoring the health of every new inhabitant at Base Alpha.
In the next four years, the human population continues to double until it reaches 14,885 as commercially paying settlers regularly arrive for 2-year excursions on Mars. A population of this size inevitably necessitates the construction of a political system to provide local policies to govern residents and push the collective agenda of “being self-sustaining as a matter of survival for the colony”. This echoes Elon Musk’s original vision of a “bottom-up emergent social order where low-cost transport infrastructure is used to build a sustainable human civilisation on Mars; the lessons from which can be used to innovate and meet the demand of growing interplanetary ventures.”
Bio-printed food begins to be served at commercial restaurants including meat grown from synthesised animal protein fibres. Bio-printing becomes the new-norm as the first mass-scale printer is used for human organ construction at the Martian hospital; donors are no longer needed from the Martian inhabitant pool. A dedicated maternity ward is also opened. A nuclear fusion powerplant begins construction using components harvested from Base Alpha, as an alternative source of energy to the solar field. This has the added benefit of reducing the demand of solar arrays sent from Earth with each mission.
16/10/46 – The Year of the Explorers
As the human population skyrockets to 66,806, Mars Base Alpha begins to look like an advanced civilization for the first time. An MRNA manufacturing facility opens in Base Alpha to vaccinate any Martian residents returning to Earth. Schools begin construction as Martian workers relocate their families permanently to Mars.
Manufacturing and industry undergo extensive development. A fully autonomous orbiting manufacturing facility is deployed in Martian orbit to send any manufactured goods to the Martian surface. The facility processes asteroids in space (to avoid atmospheric pollution on Mars) for precious materials and metals. On the surface, the first Mars Tesla Gigafactory opens to recycle solar panel batteries, assemble open and closed electric transporters and maintain all SpaceX transport vehicles.
In 2051, another perihelic opposition provides a second mass migration opportunity of human and equipment to Mars. These include government officials, mining company management teams and exploration geologists. Thanks to the advancements in AI robotics and a sustained, dedicated human effort, Mars Base Alpha reaches its objective to be fully self-sufficient for all essential goods.
02/04/53 – Another Terra Nova
The standing population of humans on Mars now reaches over 300,000 and 10,000 days of Martian colonisation is celebrated across both planets. As part of this, the first human to be born on Mars visits Earth and meets with government officials and scientists. They wear a robotic suit, controlled by Elon Musk’s “Neuralink” electrodes, to protect against Earth’s relatively heavy gravity.
On Mars, giant glass domes now house vast grasslands and tree reserves. These sit on melted ice-lakes at the Equator, where temperatures can reach a maximum of 20 degrees Celsius in the Summer. Escaped seedlings from these structures are carried by Martian winds and deposited on the surface. Thanks to terraforming efforts laid in foundation over 25 years ago, the seedlings take on the Martian surface. Against insurmountable odds, natural wild grass is found growing on Mars’ surface for the first time.
20 degrees Celsius in the Summer. Escaped seedlings from these structures are carried by Martian winds and deposited on the surface. Thanks to terraforming efforts laid in foundation over 25 years ago, the seedlings take on the Martian surface. Against insurmountable odds, natural wild grass is found growing on Mars’ surface for the first time.