Standing between two rockets that represented both the future of SpaceX and its nail-biting past, Musk delivered his talk to more than 100 people from the company's fast-developing launch site in Boca Chica, southeast Texas.
Behind Musk was a shorter rocket called Falcon 1, which – after three catastrophic failures in 2006, 2007, and 2008 – finally delivered a small payload into space for the first time. That mission's success also prevented Musk and SpaceX from going broke.
"Eleven years ago today SpaceX made orbit for the first time," Musk said of that first successful Falcon 1 launch, on September 28, 2008. "If that fourth launch had not succeeded, there would have been curtains. But fate smiled upon us that day."
Yet as he spoke, all eyes were fixed on the 164-foot-tall (50-metre-tall), stainless-steel rocket ship behind Musk that SpaceX had finished assembling only hours before his speech.
"I think this is the most inspiring thing I've ever seen," Musk said of the vehicle, called Starship Mark 1: a critical prototype for a planned system called Starship.
"There are many troubles in the world, of course, and these are important, and we need to solve them. But we also need things that make us excited to be alive," Musk said.
"Becoming a space-faring civilisation – being out there among the stars – this is one of the things that I know makes me be glad to be alive."
"Do you want the future where we become a space-faring civilisation and are on many worlds, and are out there among the stars? Or one where we're forever confined to Earth?" he said.
"I say it is the first."
But Musk's audacious vision needs a vehicle to carry it out, and to him that vessel is Starship.
SpaceX has made radical changes to its Mars rocket over the past year
In September 2018, Musk presented a carbon-fibre version of a Mars vehicle called Big Falcon Rocket. He also introduced Yusaku Maezawa, a Japanese fashion billionaire, as a major funder of the system's development – and the person who will fly around the Moon in a SpaceX rocket in 2023.
A couple of months later, though, SpaceX abandoned the carbon-fibre design and switched to a stainless-steel variant. Musk announced the reimagined spacecraft as Starship that December.
Since then, SpaceX built and launched a crude prototype called Starhopper and finished Starship Mk 1 (which Musk said may fly in a month or so). Those prototypes are work toward a Starship system that's fully reusable – that way, no multi-million-dollar rocket parts are wasted, and the only major cost to launch is fuel.
"The critical breakthrough that is required for us to become a space-faring civilisation is to make space travel like air travel," Musk said. "This is basically the holy grail of space travel."
SpaceX posted a video to Twitter (below) on Saturday that imagines how Starship would work.
Starship will be the most powerful rocket in history, capable of carrying humans to the Moon, Mars, and beyond pic.twitter.com/LloN8AQdei— SpaceX (@SpaceX) September 29, 2019
In the animation, a Starship vessel is stacked on top of a giant rocket booster, called Super Heavy, that's equipped with up to several dozen car-size Raptor rocket engines. The booster hauls Starship much of the way toward orbit, detaches, and falls back to Earth.
Once refueled, the booster then launches another Starship to meet the first one in orbit, refuel it with methane and oxygen – liquids Musk says can be mass-manufactured on Earth as well as Mars using carbon dioxide, water, and solar energy – and send it on its way.
The biggest changes to Starship's design include a refinement of its lower wings, flipper-like upper canards, and the addition of hexagon-shaped heat shield tiles lining the spacecraft's belly.
SpaceX got rid of three wings that also functioned as landing legs. Instead, Starship – as currently envisioned – now has six pop-out landing legs and two canard-like wings.
The wings and tiles are crucial to safeguarding Starship as it returns to Earth at 25 times the speed of sound and plows through the planet's atmosphere. This phase, called reentry, generates a searing-hot plasma that can destroy an unprotected spacecraft.
"For a reusable ship, you're coming in like a meteor. You don't want something that melts at a high temperature," Musk said, emphasising the need for steel (most rockets use aluminium or carbon-fibre). He also noted that stainless steel is about 50 times cheaper by weight than carbon-fibre composites.
Starship's redesigned wings should help the vehicle maintain lift, slow down more gradually, and spread out the heat of reentry, while the thermal tiles absorb that energy.
Once the ship reaches denser atmosphere, Musk said the wings will help steer Starship as it falls toward a landing pad.
"It just falls like a skydiver, and controls itself, and then it turns and just lands," Musk said. "It will be totally nuts to see that thing land."
Kimi Talvitie – a spaceflight enthusiast, software engineer, and artist – built an impressive 3D model of a "skydiving" Starship (below) using details Musk shared ahead of his presentation.
'I think we could potentially see people fly next year'
Though Starship may be years away from being fully realised, Musk shared some shocking notions about how it may stack up against all other rockets – even SpaceX's own partly reusable Falcon 9 and Falcon Heavy launchers.
Musk calculated that, in an ideal scenario, one Starship system could launch to space and return three times per day, or about 1,000 times a year. Assuming each launch can fly about 150 tons of payload into orbit, that works out to about 150,000 tons per year.
That's more than 333 times the mass of the football field-size International Space Station.
Meanwhile, he said, all of Earth's rockets launching today might together deliver no more than 300 tons into space.
"We're talking about something that is, with a fleet of Starships, 1,000 times more than all Earth capacity combined. All other rockets combined would be 0.1 percent, including ours," Musk said.
"But you kind of need that if you're going to build a city on Mars. It's gotta be done."
The rapid reusability of the system, when Musk emphasised is essential, could also move Starship into an operational state much faster.
"I think we could potentially see people fly next year," Musk said. "We can do many flights to prove out the reliability very quickly."
Musk said SpaceX hasn't yet figured out how it plans to keep people alive inside its Starships, in terms of oxygen, food, water, and waste, let alone on the surface of Mars. But he added there's a definite need for "regenerative" life support systems, which recycle and conserve all the supplies humans need.
"I think for sure you'd want to have a regenerative life support system," Musk said. "Regenerative is kind of a necessity. I actually don't think its super hard to do that, relative to the spacecraft itself."
Despite Musk's optimism, though, fully functional regenerative life support systems have yet to be achieved in elaborate facilities on Earth, let alone in spacecraft.
Musk wants to save humanity before its 'window closes'
Musk's drive in creating Starship is not just about feeling good about the future, but also, in his mind, rescuing humanity from certain doom.
"As far as we know, this is the only place in this part of the galaxy, the Milky Way, where there is consciousness," Musk said of planet Earth.
He explained that it took about 4.5 billion years for that "consciousness" – we humans – to evolve, but that we have maybe a few hundred millions years left before our ageing Sun begins to expand, heat up Earth, and make our home planet uninhabitable.
Musk referred to this as a window of time for consciousness.
"That's all we've got, OK? Several hundred million years," Musk said. "If it took life an extra 10 percent longer for conscious life to evolve, it wouldn't have evolved at all, because it'd be incinerated by the Sun."
Though this or other humanity-destroying calamities are a long way off, Musk doesn't want to waste any time while our window to spread among the stars, as is evidenced by the frenetic pace of SpaceX's Starship rocket development program.
"I'm optimistic by nature, but there's some chance that window will not be open for long," Musk said. "I think we should become a multi-planet civilisation while that window is open.
"And if we do, I think the probable outcome for Earth is even better because then Mars could help Earth one day. I think we should really do our very best to become a multi-planet species, and we should extend consciousness beyond Earth, and we should do it now."
This article was originally published by Business Insider.
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