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Lex Fridman · 2021-12-28 · 2h 31m

Elon Musk: SpaceX, Mars, Tesla Autopilot, Self-Driving, Robotics, and AI | Lex Fridman Podcast #252

Elon Musk walks Lex Fridman through Raptor engines, the Mars timeline, how Tesla's self-driving really works, humanoid robots, money as information, and the meaning of life.

Elon Musk: SpaceX, Mars, Tesla Autopilot, Self-Driving, Robotics, and AI | Lex Fridman Podcast #252
The guest

Elon Musk — CEO and chief engineer of SpaceX and Tesla, founder of multiple companies. One of the most influential figures in spaceflight, electric vehicles, and AI.

The gist

In his third appearance on the Lex Fridman podcast, Elon Musk dives deep into the engineering behind SpaceX and Tesla. He explains why production, not design, is the hardest problem, why Raptor's full-flow staged combustion engine is revolutionary, and why fully reusable rockets are the holy grail for reaching Mars. He details Tesla's approach to autonomy as recreating human vision in silicon, including building an accurate vector space, cutting latency and jitter, and replacing C++ heuristics with neural nets. The conversation ranges across the Tesla Bot, cryptocurrency as an information-theory problem, direct democracy on Mars, World War II aircraft engineering, nuclear power fears, a freewheeling meme review, and reflections on history, love, and human consciousness.

Big reveals

  • Musk says engine production, not design, is by far the biggest thing absorbing his time on Starship.
  • SpaceX plans to catch the largest flying object ever made with giant 'Chopstick' tower arms to save the weight of landing legs.
  • Musk estimates landing humans on Mars in about 5 years best case, 10 years worst case.
  • Current cost is roughly a billion dollars per ton to the surface of Mars, which must drop by a factor of a thousand or more.
  • Musk says the global money system literally runs on heterogeneous mainframes executing ancient COBOL in batch mode.
  • Musk predicts Tesla will likely solve level four full self-driving 'next year,' targeting safety 2-3x better than humans.
  • Musk admits he had never thought of the Tesla Bot as a companion, but believes it could become a very good one.
  • Musk says he might have enough material for a 15-minute stand-up comedy set and would consider a Netflix special.

Things worth remembering

  • Raptor targets 300 bar chamber pressure versus the record ~267 bar of the Russian RD engine, and 10% more pressure is ~50% harder.
  • Musk's 'magic wand number' is the cost if you could rearrange raw material atoms into the final shape, almost always a very low number.
  • Earth becomes too hot for life in about 500 million years, only 10% longer than life has existed.
  • Full and rapid reusability could cut cost per ton to orbit by a factor of 100, with a Starship launch potentially costing $1-2 million.
  • Your eyes paint in color in peripheral vision and fill in the blind spot; the brain does enormous post-processing.
  • Tesla wrote its own C compiler and runs primarily C, not C++, for maximum performance on the autopilot hardware.
  • Tesla moved to raw photon counts instead of post-processed images, saving 13 milliseconds of latency and seeing better in the dark.
  • In WWII, Germany had great aircraft designs but lacked consistent high-octane fuel and quality aluminum alloys, unlike the US.
  • Musk notes coal plants are roughly 100 to 1,000 times worse for health than nuclear power plants.
  • Musk warns against a 'zero-sum mindset' and urges creating more than you consume, since the economic pie is not fixed.

Recommended in this episode

Books, products and media the guest or host genuinely endorsed here — with the buy link.

Affiliate link — we may earn a commission at no extra cost to you.

RecommendedMedia

Inspiration4 documentary

Netflix

“I'd encourage people to watch the inspiration documentary on Netflix it's actually really good um and it really is” — Elon Musk 00:03:41
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Guest’s ownProduct

Raptor engine

SpaceX

“Raptor is a full flow staged combustion engine and it's at operating at a very high chamber pressure” — Elon Musk 00:09:25
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Guest’s ownProduct

Starship

SpaceX

“Starship is the most complex and advanced rocket that's ever been made by I don't know order of magnitude” — Elon Musk 00:28:08
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Guest’s ownProduct

Falcon 9

SpaceX

“right now the falcon9 is the only reusable rocket out there but the booster comes back and lands” — Elon Musk 00:38:29
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Tesla Autopilot / Full Self-Driving

Tesla

“I think over time the tesla autopilot full driving will be capable of Maneuvers that are far more than what James Bond could do” — Elon Musk 01:26:41
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Guest’s ownProduct

Tesla Bot (Optimus)

Tesla

“it's code named Optimus I call I call it Optimus subprime because it's not like a giant transformer robot” — Elon Musk 01:39:53
Find it on Amazon
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Hardcore History

Dan Carlin

“you're a student of History fan of Dan Carlin's Hardcore History Podcast yeah that's great greatest podcast ever” — Lex Fridman 01:46:43
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The Entire Soviet Rocket Engine Family Tree

Tim Dodd (Everyday Astronaut)

“a video titled the entire Soviet rocket engine family tree by Tim Dodd AKA everyday astronaut people should definitely go check out” — Lex Fridman 01:58:13
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Rick and Morty

Justin Roiland and Dan Harmon (inferred)

“there's the butter robot it's great uh it's a great show you yeah Dr Mor is awesome” — Elon Musk 02:16:32
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Monty Python's Life of Brian

Monty Python

“I always love Monty Python they're great uh Life of Brian and the quest of Holy Grail are incredible” — Elon Musk 02:11:20
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Monty Python and the Holy Grail

Monty Python

“I always love Monty Python they're great uh Life of Brian and the quest of Holy Grail are incredible” — Elon Musk 02:11:20
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RecommendedBook

Encyclopaedia Britannica

Encyclopaedia Britannica (inferred)

“read through the condensed version of the encyclopedia britannica I'd recommend that you can always skip subjects” — Elon Musk 02:22:49
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