For astrophysicist Adam Becker, the colonisation of Mars, advocated by Elon Musk as a rescue plan for humanity, is more fantasy than viable strategy. Even in the worst-case scenarios on Earth, our planet would still be infinitely more habitable than the icy desert of Mars.

Elon Musk’s Martian dream called into question

Elon Musk, CEO of SpaceX, makes no secret of his ambition to turn humanity into a multi-planetary species. At the heart of his vision is the colonisation of Mars, seen as a “lifeboat” in the event of an earthquake. But according to astrophysicist and author Adam Becker, this idea is a technological optimism out of touch with physical reality.

In an interview with Rolling Stone, Becker doesn’t mince his words: “That’s one of the stupidest things anyone can say.”

Three disaster scenarios… and yet

To support his point, Adam Becker imagines three apocalyptic scenarios:

An asteroid the size of the one that wiped out the dinosaurs.

The explosion of all the nuclear bombs on the planet.

Uncontrollable global warming.

In each of these extreme cases, Becker claims that Earth would remain more hospitable than Mars. Why should this be? Because, even when ravaged, our planet retains some fundamental elements: a breathable atmosphere, suitable gravity, accessible water and protection from radiation.

Mars, an icy, barren hell

Even after a cataclysm, the Earth would remain much more hospitable than Mars is today. Its atmosphere, rich in oxygen and nitrogen, would remain breathable, whereas Mars’ atmosphere, composed of 95% carbon dioxide, has a pressure so low that it is completely unbreathable. The Earth’s temperature could fall, but would remain less extreme than that of the Red Planet, which is frozen at around -63°C. As far as water is concerned, the Earth would retain its oceans, even if contaminated, whereas Mars only contains ice that is deeply buried and difficult to access. The Earth would also retain its magnetic field, which is essential for blocking cosmic radiation, unlike Mars, which is totally exposed. Finally, the Earth’s soil would still contain organic matter, whereas that of Mars, rich in toxic perchlorates, represents a danger for any form of cultivation.

On Mars, life would only be possible under pressurised domes, and any failure in a vital system would mean immediate death. On Earth, even after a global disaster, pockets of life could survive and rebuild.

Terraforming Mars: an illusion?

Elon Musk imagines a red planet made habitable by human ingenuity: exploding the poles with nuclear bombs, giant mirrors in space, air-conditioned greenhouses… But to turn Mars into Earth 2.0, we’d need :

Release enough CO₂ to thicken the atmosphere.

Create a long-lasting greenhouse effect to heat the planet.

Make an artificial magnetic field to protect it.

Even if all the stored CO₂ were released, the pressure would only exceed 7% of that on Earth, insufficient to survive without a pressurised suit. Not to mention the titanic cost of transporting materials, food, water and humans 55 million kilometres.

Becker concludes: investing in survival on Mars would be like abandoning a ruined hospital to go and survive in a radioactive desert with no oxygen : “It’s better to preserve our planet, even if it’s wounded, than to exile ourselves to a giant open-air chamber.”

In the absence of a credible interplanetary Plan B, the priority here remains preserving this blue jewel suspended in the vacuum of space, the only one to offer life until proven otherwise.