Humanity could settle Mars by 2055, Elon Musk says

A Red Planet settlement isn't a mere pipe dream, according to Elon Musk.

The SpaceX founder and CEO thinks humanity can get a sustainable, self-sufficient Mars settlement up and running by 2055, as long as we make some key advances with our heavy-lift launch technology.

"I think it can be done in in 30 years, provided there's an exponential increase in the tonnage to Mars with each successive Mars transfer window, which is every two years," Elon Musk said via video on Sept. 9 during the All-In Summit, an event organized by the All-In podcast. (Earth and the Red Planet align properly for interplanetary missions just once every 26 months.)

Ramping up the tonnage is important, he stressed, because a Mars settlement will need lots of stuff, from habitat modules to helper robots. And, to be truly self-sufficient, it will also need "to have all of the ingredients of civilization," Musk said — the materials that will enable settlers to grow food, generate fuel from the Martian atmosphere and build microchips, computers and rockets, among many other things.

Musk has one particular rocket in mind to make this Red Planet dream come true — SpaceX's Starship, the biggest and most powerful launch vehicle ever built.

Starship consists of two elements, both of which are designed to be fully and rapidly reusable — a booster called Super Heavy and an upper-stage spacecraft called Starship, or Ship for short. Both are made of stainless steel and powered by SpaceX's next-gen Raptor engine, which burns liquid oxygen and liquid methane (both of which can be produced on Mars, Musk has stressed).

The vehicle is still under development. It has flown in a fully stacked configuration 10 times to date, most recently on Aug. 26. Flight 10 went well; Starship notched all of its main mission milestones, including its first-ever payload deployment in space (eight dummy versions of SpaceX's Starlink broadband satellites).

This was an important bounce-back mission for Ship, which was lost prematurely on the previous three Starship test flights.

The next Starship test flight will be the final launch of the vehicle's current Version 2 design, Musk said at the All-In Summit.

"Thereafter, it's Version 3, which is a gigantic upgrade, because that's got Raptor 3, and pretty much everything changes on the rocket," he said, referring to the next engine iteration. "So, Version 3 might have some initial teething pains because it's such a radical redesign, but it's capable of over 100 tons to orbit, fully reusable."

That's about 2.5 times the lift capacity of SpaceX's Falcon Heavy rocket in reusable mode, he noted. But the Heavy, like its cousin the Falcon 9, is only partially reusable; the vehicle's upper stage is expendable. Each Super Heavy and Ship, by contrast, will fly many times, if all goes according to plan.

SpaceX has already demonstrated reusability with Super Heavy, flying the same booster on both Flight 7 and Flight 9. But it has yet to do so with Ship, which is understandable given the challenges involved.

"For full reusability of the Ship, there's still a lot of work that remains on the heat shield," Musk said.

"No one's ever made a fully reusable orbital heat shield. The [space] shuttle heat shield had to go through nine months of repair after every flight," he added. "We really are looking at the fundamental physics here — again, physics first principles, and trying to figure out, 'How do we make something that can withstand the heat, is very light [and] doesn't transmit the heat to the primary structure?' And then, all the tiles stay on and they don't crack."

Still, Musk voiced optimism about SpaceX's ability to clear such hurdles in a timely fashion.

"I think, unless we have some very major setbacks, SpaceX will demonstrate full reusability next year, catching both the booster and the Ship, and being able to deliver over 100 tons to a useful orbit," he said.

(Starship's eventual flight plan involves both Super Heavy and Ship coming back to the launch pad, where they'll be snagged by the "chopstick" arms of the launch tower.)

Starship Version 3 will stand about 408 feet (124.4 meters) tall, compared to Version 2's 397 feet (121 m), Musk has said. Version 3 will be the first iteration of the vehicle that can fly to Mars — and SpaceX hopes to launch the first uncrewed test flights to the Red Planet with it next year.

But most of the Mars-settlement heavy lifting could be done by an even bigger Starship: Musk has said the vehicle will eventually stand a whopping 466 feet (142 m) tall when fully stacked.

Musk will likely stay committed to the Mars-settlement goal over the long haul, as it has long been a driving force for him and SpaceX. Indeed, Musk has stressed that he founded the company in 2002 primarily to help humanity expand its footprint beyond Earth.

"What really matters is that Mars is self-sustaining, that we are truly a multi-planet species, such that we've achieved planetary redundancy," he said at the All-In Summit. "There's always some risk of an annihilation event on Earth — like I said, self annihilation, or some natural disaster — and so the probable lifespan of consciousness increases dramatically as soon as we are a multi-planet species, with the key test being: Can [the settlement on] Mars survive if the resupply ships stop coming?"