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Elon Musk Proposes City-to-City Travel By Rocket, Right Here on Earth (theverge.com)
SpaceX CEO Elon Musk unveiled revised plans to travel to the Moon and Mars at a space industry conference today, but he ended his talk with a pretty incredible promise: using that same interplanetary rocket system for long-distance travel on Earth. From a report: Musk showed a demonstration of the idea onstage, claiming that it will allow passengers to take "most long-distance trips" in just 30 minutes, and go "anywhere on Earth in under an hour" for around the same price as an economy airline ticket. Musk proposed using SpaceX's forthcoming mega-rocket (codenamed Big Fucking Rocket or BFR for short) to lift a massive spaceship into orbit around the Earth. The ship would then settle down on floating landing pads near major cities. Both the new rocket and spaceship are currently theoretical, though Musk did say that he hopes to begin construction on the rocket in the next six to nine months. In SpaceX's video that illustrates the idea, passengers take a large boat from a dock in New York City to a floating launchpad out in the water. There, they board the same rocket that Musk wants to use to send humans to Mars by 2024. But instead of heading off to another planet once they leave the Earth's atmosphere, the ship separates and breaks off toward another city -- Shanghai. Just 39 minutes and some 7,000 miles later, the ship reenters the atmosphere and touches down on another floating pad, much like the way SpaceX lands its Falcon 9 rockets at sea. Other routes proposed in the video include Hong Kong to Singapore in 22 minutes, London to Dubai or New York in 29 minutes, and Los Angeles to Toronto in 24 minutes.
There is no way that this craft could be made safe enough for people to trust it. First accident, and no one wants to use it anymore.
There is also no way the launch cost and infrastructure required could be made affordable for city to city travel. Even a Concorde turned out to be unaffordable over the long term, and that was quite a bit simpler than this scheme.
HBI's Law: Frequency of calling others Nazis is directly correlated with the likelihood of the accuser being Communist.
Elon has been saying a lot of things recently, doesn't mean it'll all come true.
Not necessarily. Unfortunately a lot of people advocating environmentalism don't have a clue about opportunity cost. It's incorrect to compare this to a zero base state - if the travel didn't happen at all. The correct comparison is to what would happen if this rocket travel weren't available. i.e. what happens right now? People fly between these locations. So the correct comparison is the monetary and pollution cost of a plane vs. rocket.
I haven't done the math, but I can see where Musk is going with this. The vast majority of the energy used by a plane on these long flights is overcoming friction with the air. A rocket eliminates that frictional energy loss by traveling above the air. In other words, the energy cost to fly on long flights is pretty close to proportional to the distance flown. While the energy cost to achieve a sub-orbital trajectory is very close to fixed (a fraction of escape velocity, with a slight increase in velocity translating into a very large change in distance traveled). So there's a certain distance beyond which the rocket will require less energy than a plane. If you can get the price of the technology down enough, a rocket between destinations greater than that distance will be both cheaper and less polluting than flying. The trip being quicker is just gravy.