Elon Musk’s plans to go to Mars... within two years

There are few public figures who provoke as much controversy as Elon Musk, the founder of SpaceX. His outlandish statements, extravagant lifestyle and political interference make him seem like a James Bond baddie bent on conquering – and perhaps destroying – the world.

But there is another side to Musk, that of an excellent engineer and visionary. Whether this is due to his cutting-edge ideas or his ability to surround himself with top engineers, the fact is that in just a few years, his companies Tesla and SpaceX have brought about a true revolution in their sphere; others, such as Neuralink, have the potential to do so in the future. He is the one who has insisted on implementing concepts such as the recoverable rocket.

Musk is known for his surprising statements and predictions. Reality has shown that many of them have come true, albeit far more slowly than predicted. Now he has just announced his intention to send not one but five unmanned spacecraft to Mars, taking advantage of the launch window that will open in 2025.

Musk’s ultimate goal is to launch his Starship super rocket at hourly intervals. This is why it’s important that its lower half was able to maneuver back beside its launch tower. That way it can be quickly placed on the launch pad, so that the condition of the engines can be checked, the damaged ones replaced and a second stage attached. It can then be refueled and launched again.

Could such a pace be maintained? Not right now, as the bottom part of the rocket, known as the Super Heavy booster, is still undergoing tests, but two years down the road it seems feasible. In Boca Chica, Texas, there are already two launch towers, although the second one has not yet been inaugurated. A third has been erected on Ramp 39A at the Kennedy Center. When all three are operational, SpaceX could theoretically launch three Super Heavy boosters almost simultaneously.

The Super Heavy booster is recoverable, and each mission lasts less than a quarter of an hour, which is the time it takes to reach an altitude of about 70 kilometers, slow down and return to base. So, it would be enough for SpaceX to have a fleet of three launchers, one per pad. Maybe two or three more as a precaution. After all, they are relatively inexpensive; the most expensive thing is the propulsion plant with its 33 Raptor engines.

Today, SpaceX is producing engines at a rate of one per day. With the upcoming introduction of a new model, which makes extensive use of 3D printing, that figure could be doubled.

Why the launch frenzy? Because the second stage, which includes the Starship, only has enough fuel to travel into Earth’s orbit. Future missions to the Moon or Mars will require refueling with methane and oxygen mid-flight, which is another critical operation that has yet to be tested.

SpaceX engineers plan to use a fleet of tanker spacecraft that will automatically dock with the main spacecraft to refill its tanks as fast as possible to avoid evaporative losses. Each interplanetary trip will require between six and twelve freighters that may or may not be recoverable.

Musk estimates that the cost of each recharge launch will be minimal. The first stage, which is the most expensive, is recoverable; the second stage is little more than a casing that is manufactured at the Boca Chica industrial complex, right next to the ramp. It is cheap and quick to build, as it is made of stainless steel rather than exotic materials such as lightweight aluminum alloys and carbon fiber. Although many of the details remain under wraps, it appears that SpaceX assembles these casings almost in series, directly from the metal coils as they arrive from the rolling mill.

The bottleneck may lie in the supply of the thousands of liters of methane and oxygen needed to maintain a sustained hourly launch rate. Currently the “tank farm” adjacent to the launch tower is sufficient to fill one rocket, but not several in quick succession. Both Boca Chica and Kennedy are on the coast, so some have proposed building a jetty and a small gas pipeline so that the fuel can arrive in large methane tankers.

In principle, the orbital fuel freighters will also be recoverable, which means providing them with protection from the heat of re-entry. Each carry only six engines, which may be worth reusing although they also do not represent an inordinate cost and, if time is of the essence, Musk could opt to let them be destroyed after delivery. It wouldn’t be the first time. On the recent Europa Clipper launch, which required a high exit velocity, SpaceX decided to lose all three rocket bodies in order to squeeze every last drop of fuel out of them.

In any case, after the successful capture of the first stage, it is likely that subsequent efforts will be directed towards the very complicated maneuver of refueling in space. Apart from Musk’s plans to explore Mars, the fact is that this operation will be essential for the lunar lander NASA has contracted as part of the Artemis program to go to the Moon. Mars has no date except in Musk’s diary; the Moon does.

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