9.04.2024

"These are unthinkable numbers, but we’re not breaking any physics to achieve this."

Elon Musk has been talking publicly about his sweeping vision for Mars settlement for nearly eight years now, dating to a speech in Guadalajara, Mexico, in September 2016.

This weekend, at SpaceX's Starbase facility in South Texas, Musk once again took up the mantle of his "making life multiplanetary" cause. Addressing employees at the location of the company's Starship factory, Musk spoke about the "high urgency" needed to extend the "light of consciousness" beyond Earth. That is not because humanity's home planet is a lost cause or should not be preserved. Rather, Musk said, he does not want humanity to remain a one-planet civilization that will, inevitably, face some calamity that will end the species.

All of this is fairly familiar territory for spaceflight enthusiasts—and observers of Musk. But during the last eight years he has become an increasingly controversial and polarizing figure. Based on his behavior, many people will dismiss Musk's Mars comments as those of a megalomaniac. At least in regard to spaceflight, however, that would be wrong. Musk's multiplanetary ambitions today are more credible because SpaceX has taken steps toward doing what he said the company would do.

SpaceX has real hardware today and has completed three test flights. A fourth is possible next month.

"It’s surreal, but it’s real," Musk said this weekend, describing the audacious Mars vision.

The booster and ship

As part of his 45-minute speech, Musk spoke about the booster for Starship, the upper stage, and the company's plans to ultimately deliver millions of tons of cargo to Mars for a self-sustaining civilization.

If thousands of launches seem impossible, Musk noted that SpaceX has now completed 327 successful Falcon launches and that 80 percent of those have involved used boosters. This year, he said, SpaceX will launch about 90 percent of the mass sent into orbit from the planet. China will launch about 6 percent, he added, with the remainder of the world accounting for the other 4 percent.

This kind of performance has given Musk confidence that reusability can be achieved with the Super Heavy booster that powers Starship. On the vehicle's next test flight, possibly in May, the company will attempt to land the booster on a virtual tower in the Gulf of Mexico. If that landing is precise enough, SpaceX will try to catch the booster on the fifth test flight with the chopstick-like mechanisms on Starship's massive launch tower.

The Raptor rocket engine will see performance upgrades.

"That’s very much a success-oriented schedule, but it is within the realm of possibility," Musk said. With multiple test flights occurring this year, Musk said the odds of catching the booster with the launch tower this year are 80 to 90 percent.

It will take longer to land and begin reusing Starship's upper stage, which must survive the fiery reentry through Earth's atmosphere. This vehicle broke apart and burned up during its attempt to return through the atmosphere during a flight test in March. On the next flight, Musk said, the goal for Starship's upper stage is to survive this heating and make a controlled landing in the ocean. At some point this year, he expects SpaceX to achieve this milestone and then begin landing Starships back in Texas next year.

Building more, building bigger

SpaceX is also building additional ground-based infrastructure and making design upgrades to Starship.

Musk said the company will construct a second launch tower in Texas to facilitate additional developmental test flights. And by the end of 2025 it intends to have two Starship launch towers in Florida to begin supporting operational launches. Initially, these are likely to support Artemis lunar landing missions for NASA.

The company plans to build six additional Starship vehicles this year and increase that production in 2025 as a new factory comes online at the Starbase facility.

Starship will also get bigger, primarily by expanding its length. Musk outlined the company's plans for a "Starship 2," capable of launching 100 tons to low-Earth orbit in fully reusable mode, and "Starship 3," with a capacity of 200 or more tons. If this seems unrealistic, consider that SpaceX performed four major block upgrades to the Falcon 9 rocket from 2010 to 2018, more than doubling its performance.

These larger vehicles will be necessary to reduce the number of refueling missions required to load a vehicle in Earth orbit for a trip to the Moon or Mars. Musk said the goal is to reach a configuration such that it will only take five or six refueling missions to support a Starship that can land 200 tons on Mars.

The final Starship 3 vehicle will be about 500 feet (150 meters) tall, about 20 percent larger than the current vehicle. This will allow for additional propellant to increase lift capacity. Musk said the company should be able to launch Starships for less than the original price of the Falcon 1 rocket, which was $6 million. Starship would carry 400 times the payload, however.

"These are unthinkable numbers, but we’re not breaking any physics to achieve this," Musk said.

Millions of tons to Mars

Ultimately, Musk's goal is to seed a civilization on Mars as humanity's first step toward becoming a multiplanetary species. To accomplish this, he believes Mars will need a population of about 1 million people, with many millions of tons of supplies so that settlers can mine and build and grow things on Mars to become self-sustaining.

This will require an absurd amount of launches, 10 per day, and the dispatch of a fleet of hundreds of vehicles to Mars during the short-trip trajectory window that opens between Earth and the red planet every 26 months. Ultimately, while it is challenging, Musk believes that humans could terraform a "fixer-upper" planet like Mars.

Getting to Mars? It's complicated.

How much you buy into this vision will undoubtedly depend on your predilection toward Musk and your sense of the difficulty of forging habitable communities on an uninhabitable world like Mars. The engineering challenges are extraordinary. But people have been underestimating SpaceX for years. Generally, the company's talented employees have done what Musk has said they would do. Why stop now?

Eight years ago, when Musk first outlined his Mars plans, I characterized them as "audacity, madness, and brilliance." I still believe all three adjectives apply. If anything, the vision is more audacious. But as of today, with SpaceX having proven that rocket reusability is a very viable thing and with a vibrant Starship factory at hand, they do seem a little less mad.

"We can do this," Musk told his employees this weekend. I'm not sure he's wrong.

Quelle: arsTechnica