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Earth Transportation

Elon Musk Proposes City-to-City Travel By Rocket, Right Here on Earth (theverge.com) 318

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.
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Elon Musk Proposes City-to-City Travel By Rocket, Right Here on Earth

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  • by BenJeremy ( 181303 ) on Friday September 29, 2017 @11:10AM (#55277181)

    Nothing but the best for the best people.

  • Isn't this the same guy who's pushing Solar Power and electric cars to save the environment? Wouldn't those rockets create an awful lot of poisonous gasses? No sir! Just take your time and sail there on a solar/wind powered boat!
    • by c++ ( 25427 )

      What do you think a methane-oxygen burn produces? lead?

      • Re:Wait a minute... (Score:4, Interesting)

        by avandesande ( 143899 ) on Friday September 29, 2017 @11:16AM (#55277247) Journal
        The point stands though that this is incredibly wasteful
        • Re:Wait a minute... (Score:4, Interesting)

          by decep ( 137319 ) on Friday September 29, 2017 @11:20AM (#55277289)

          So does keeping servers powered on 24x7 to host a web site for making "Beowulf Cluster" and "In Soviet Russia" jokes, but you don't see me not complaining.

        • The point stands though that this is incredibly wasteful

          The biggest thing wasted is money... How much is a one way ticket? Even with economy of scale you're probably going to be paying thousands for a ticket.

          Still... that probably means saving time.

        • Re:Wait a minute... (Score:4, Interesting)

          by ShanghaiBill ( 739463 ) on Friday September 29, 2017 @11:36AM (#55277459)

          The point stands though that this is incredibly wasteful

          Elon said it would cost the same as an economy class ticket ... which means it would have to consume about the same amount of fuel per person as a conventional aircraft flight. Otherwise the cost couldn't be so low.

        • by phayes ( 202222 )

          So you are certain that pushing a column 747 sized of air out of the way all the way from taking off in NYC all the way to landing in Singapore is less wasteful than boosting over the atmosphere then using the atmosphere to slow back down and perform a landing burn? I suspect not.

          Musk, on the other hand _has_ performed those calculations and determined that costs should be comparable.

        • by Solandri ( 704621 ) on Friday September 29, 2017 @12:19PM (#55277995)

          The point stands though that this is incredibly wasteful

          Not necessarily. Unfortunately a lot of people advocating environmentalism don't have a clue about opportunity cost [wikipedia.org]. 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.

          • Re:Wait a minute... (Score:4, Informative)

            by nukenerd ( 172703 ) on Friday September 29, 2017 @01:36PM (#55278805)

            The point stands though that this is incredibly wasteful

                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.

            Nope. Jevons paradox kicks in. If you can get between London and New York in 25 minutes for no more cost than an airline economy ticket, more people would be doing it than now, negating any savings in fuel consumption. Like aircraft are more efficient than ocean liners in terms of fuel per passenger-mile, but far more people travel by aircraft now than by ship in the 1930's and the total fuel consumed is greater.

            Costs of space rockets compared with aircraft is not just about fuel. Rockets structures are more minimal than aircraft so are very highly stressed (to save weight). The amount of inspection, looking for fatigue cracks etc, that re-usable people-carrying rockets would have to undergo will be very expensive.

        • Re:Wait a minute... (Score:5, Informative)

          by Thelasko ( 1196535 ) on Friday September 29, 2017 @03:39PM (#55279781) Journal

          The point stands though that this is incredibly wasteful

          The idea is to eventually create the methane fuel via the Sabatier process [wikipedia.org] which converts carbon dioxide and water into methane. This is a necessary capability to refuel on Mars. Using solar energy to power the fuel manufacturing process would essentially make this vehicle solar powered.

          Most noxious emissions from combustion are due to:

          • A. Oxygen reacting with nitrogen from the atmosphere. Which isn't a problem since rockets don't use air, but instead carry their own oxidizer.
          • B. Incomplete combustion. Which can be mitigated with careful engine development.

          Once out of the earth's atmosphere, aerodynamic drag goes away. Which also might save some energy.

          Please watch the entire talk. [youtube.com] It's very informative.

      • It produces water and carbon dioxide. Water isn't a big deal, but CO2 is.

        • It produces water and carbon dioxide. Water isn't a big deal, but CO2 is.

          Its OK. Only the rich will be able to fly. Their CO2 emissions are less of a concern than those of joe public.

  • Comment removed (Score:5, Insightful)

    by account_deleted ( 4530225 ) on Friday September 29, 2017 @11:11AM (#55277195)
    Comment removed based on user account deletion
    • Re: (Score:2, Funny)

      by Anonymous Coward

      Pfff.... it already happened. In the year 3000 there are already transport tubes in New New York. You just get in, say something like "Take me to Planet Express", and you're taken there within a matter of seconds.

    • Pretty sure safety isn't the issue. We don't allow supersonic flights because they're obnoxious - a rocket isn't much different in that regard. At best this drops it to a 30 minute flight plus 2 hours commuting each way away from civilization to get somewhere they are allowed to take off and land from.
      • Plus the 2 hour time buffer you need for TSA purposes.

        Seriously, in most of the flights that I've taken since the turn of the century, the actual time in flight hasn't been where most of the time required for travel is.

        • by D.McG. ( 3986101 )
          I don't see Musk hiring the TSA at his spaceports. The TSA certainly would not be in other countries. Any lines for competent screening (95% failure rate, what a joke) would be for the one and only launch that hour. Usually, delays with the TSA are due to dozens of gates all utilizing one funnel point for screening.
      • by hawguy ( 1600213 )

        Pretty sure safety isn't the issue. We don't allow supersonic flights because they're obnoxious - a rocket isn't much different in that regard. At best this drops it to a 30 minute flight plus 2 hours commuting each way away from civilization to get somewhere they are allowed to take off and land from.

        Safety is an issue, their rocket will need to approach airline levels of safety before it'll become popular, the Falcon 9 is no where near that. It has a perfect 10/10 record for 2017 (so far), a commuter aircraft may do 10 trips a *day* for a decade with no significant incidents. 2016's record was less impressive -- out of 9 launches, there was one on-pad loss of payload, and 3 landing failures. How many people would fly in an airplane if they had a nearly 50% chance of dying?

        In any case, even adding a fe

    • Airplanes have crashes on occasion and people still take them. If something is cheap enough and quick enough, people will do it once it becomes routine. Furthermore, like airplanes, one gets more safety as one runs it more since one has more data about what minor things have gone wrong or things have almost gone wrong, and since all the rockets are reusable one is getting much better data than one would for disposable rockets since one can inspect the craft after.

      The real issue is going to be cost; in t

      • by phayes ( 202222 )

        Using _today's_ solar power infrastructure it would massively increase the cost of producing his CM4+02 from H20+CO2. How can you be certain that this will also be the case in the future?

        • Um, I'm not certain. Notice that I said "could massively increase the cost" not that it would do so.
          • by phayes ( 202222 )

            But why even say it when you have little/no certitude that it is the case? That unfounded assertion is the only reason I replied.

      • by hawguy ( 1600213 )

        Airplanes have crashes on occasion and people still take them. If something is cheap enough and quick enough, people will do it once it becomes routine. Furthermore, like airplanes, one gets more safety as one runs it more since one has more data about what minor things have gone wrong or things have almost gone wrong, and since all the rockets are reusable one is getting much better data than one would for disposable rockets since one can inspect the craft after.

        Plenty of people are still afraid of flying even though airplanes are one of the safest forms of travel possible -- in 2016 there were 2 accidents per million departures.

        The Falcon 9 has a perfect launch record in 2017 (13 out of 13 successful launches), and a perfect landing record (10 out of 10 attempts - 3 launches intentionally did not land). But in 2016, 4 out of 9 trips had failures (1 exploded on the launch pad, 3 failed on landing).

        It's going to take a lot more trips and a more than a decade from no

    • by phayes ( 202222 ) on Friday September 29, 2017 @11:51AM (#55277639) Homepage

      The same exact thing was said about steam trains when they started going faster than the animal drawn conveyances of the day.

      My god man! At speeds over 75MPH all the air will be sucked out of the cabins and everyone will suffocate!

      Thanks for being _that guy_...

      • The old "they laughed at Einstein" fallacy. Thanks for being _that guy_ ...
        • by phayes ( 202222 )

          It's not a fallacy when it's true.

          Do you doubt that airplanes were considered deathtraps 100 years ago? Do you assert that the general opinion on rockets cannot change now that they are passing from expendable to reusable? Do you have anything intelligent to say on the matter or are you just here to snipe?

          • by WrongMonkey ( 1027334 ) on Friday September 29, 2017 @01:38PM (#55278831)
            A fallacy is always a fallacy. You are dismissing criticism of a proposed concept simply by saying that previous ideas were also criticized.

            Airship, flying cars, jet packs were all consider impractical and unsafe. Decades later they are still impractical and unsafe.

            Do you have anything intelligent to say on the matter or are you just here to snipe?

            Of course I'm just here to snipe. The entire proposal has all the rigor and detail of an Alpha Centauri Secret Project cut scene. Nothing intelligent can be said about it.

    • 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.

      Every form of travel ever had the 'first accident.' There are accidents all the time with airplanes. Somehow we still manage to get on them.

    • 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.

      The same was said of commercial air travel.

      There is also no way the launch cost and infrastructure required could be made affordable for city to city travel.

      Assuming the equipment and infrastructure can be built to support extreme re-usability (which is a tall order, but there's no reason in principle that it should be impossible), the real question is fuel costs. In another post on this thread JoshuaZ estimated that each sub-orbital launch would require about 900 tons of methane propellant. At current industrial prices of about $4 per 1000 cubic feet, that's about $140K. Assuming 200 passengers, that's $700 per passen

  • by coolmoe2 ( 3414211 ) on Friday September 29, 2017 @11:14AM (#55277221)
    Launch signatures like that headed for their cities. What could possibly go wrong.

    Well this is one way to test anti missile tech

    • The "launch signature" for this would be very different than that of missiles. It would be trivial to tell the difference.

  • by Crashmarik ( 635988 ) on Friday September 29, 2017 @11:15AM (#55277235)

    Will eat up all the time savings. Instead of sitting in a plane flying to your destination, you will be spending time putting on a pressure suit and sitting in a rocket being readied for takeoff.

  • This reminds me (Score:5, Interesting)

    by vadim_t ( 324782 ) on Friday September 29, 2017 @11:17AM (#55277261) Homepage

    I have been wondering one related thing: It seems that the Falcon 9 is built just around the maximum size they can manage to move by road.

    Now that the rocket has become reusable, could they work around the transport issue by launching the empty rocket from the manufacturing plant and having it land right at the launch pad?

    If this is actually viable it could be huge -- build wherever it's most comfortable to build, launch wherever it's most comfortable to launch. I imagine satellites are far easier to ship than the entire rocket, so this might even work to change the launch site to avoid bad weather.

    • That's thinking with portals...er reusable rockets.
    • Currently, it still has to be carried from the build facility to the launch pad by one of these. https://en.wikipedia.org/wiki/... [wikipedia.org]

      • by vadim_t ( 324782 )

        They get carried over public roads as well: https://i.ytimg.com/vi/oNTuSm3... [ytimg.com]

        I remember reading somewhere that the Falcon 9 is just about as big as it can be to still make this possible.

      • by jae471 ( 1102461 )

        That's a Saturn V/STS/SLS crawler-transporter. It's not used for Falcon.

        The Falcon 9 is moved from factory to launch site using a much more basic/standard trucking rig, on the highway (See Core Spotting [nasaspaceflight.com] for pics of it on the road.) When it gets to the launch site, it's placed on the transporter-erector-launcher (TEL) and mated to the second stage (which is also road-transported) and payload. The TEL moves it from the horizontal integration facility (HIF) to the actual pad.

        SLC-39A [google.com] The current sat image of S

    • by jeti ( 105266 )
      They won't be allowed to launch a rocket over land for a long time. Noise is also a big issue.
  • This looks to me like it would be one of the coolest ways to die.

  • by Rick Schumann ( 4662797 ) on Friday September 29, 2017 @11:27AM (#55277373) Journal
    He's just trying to get in the headlines. No way this would be practical.
  • I guess the question is, are your meetings/trips really so important and your time so limited that you feel like rolling the dice of a 1-in-10-"ish" chance of not making it to your meeting... forever?

    Maybe for Elon Musk, since he views every passing minute as another tick of the clock of his limited time here on Earth. But maybe for the rest of us mere mortals, planes are still ok enough....
    • by phayes ( 202222 )

      You mean like they said 100 years ago about heavier than air travel? Yeah because it's certain that THAT never happened, did it...

  • Given how fit one needs to be to survive the G-Forces (named from "Gee whiz, everything's going black!") inherent in a launch like this I'd suspect many people wouldn't get health clearance to make these kinds of trips.

  • I seriously can't imagine a method of inter-city travel that would be worse for the global environment.

    • by phayes ( 202222 )

      Yeah, because pushing an airliner sized column of air out of the way from takeoff to landing with kerosene powered jet engines is soooo much better than boosting over the atmosphere, coasting, performing a retro-burn, braking passively and performing a landing burn. You _know_ this do you? Post your calculations so we can laugh a little more...

      • Post your calculations so we can laugh a little more...

        Why are you asking me to support an assertion that I never made?

        • But your statement was so definitive that it implied you had an informed opinion. Sorry for assuming you knew what you were talking about.

          • by phayes ( 202222 )

            Precisely.

            I got more laughs anyway when he couldn't figure out why I called him out on pretending to know more than he does.

            What was the Samual Clemens aphorism? A wise fool knows that is better to be thought a fool and stay quiet than it is to speak and remove all doubt.

      • For a regular Falcon9, just getting launched (no landing burn) is 220 metric tons of CO2. Given that it has a weight capacity of 11 metric tons we can guess it can carry maybe 100 people (That would give up 220kg for the person, life support, luggage, retro fuel etc.) So, at 2.2 tons of CO2 per passenger, that is 10% more than an airplane at 1.8-1.95 tones of CO2 per passenger on intercontinental flights. And you have to add for the retro-burn and landing burn.

        I also think that 220kg per passenger (cou

  • So these rocket taxis... do they count as flying cars?
    Also, is life insurance part of the ticket price?
  • Prior Art (Score:5, Funny)

    by Tablizer ( 95088 ) on Friday September 29, 2017 @11:36AM (#55277453) Journal

    NK already has them, but they only sell one-way tickets.

  • But the baggage fees with be insane!

  • I love it though. If he does 10 things like this and 1 thing works and is safe, it would be HUGE!

    Thank god someone with billions is trying to crate disruptive technologies. I think he knows that he might end up loosing money overall but I don't think having just $1 billion 10 years from now is going to bother him.

  • Illustration that shows the same type of aerodynamic shaped spaceship on Pad 39, docked to ISS, and sitting on surface of Mars looks so 1950s like Chesley Bonestell paintings from the day. Nice paintings but those don't take into account the Rocket Equation. Yes, Musk demonstrated reusable rockets (with a big boost of govt money) but this Mars fantasy is a huge distraction. For past 50 years they've said we will be on (sending humans) to Mars.
    • by Megane ( 129182 )
      I think the real problem with humans on Mars will turn out to be the effects of space on the human body, as we are starting to learn with ISS. Even with good solar-ion engines to speed up the trip, we may still need centrifugal crew quarters.
  • by hawk ( 1151 ) <hawk@eyry.org> on Friday September 29, 2017 @11:48AM (#55277583) Journal

    He is not "proposing" this idea--he's suggesting he can implement it.

    The notion of suborbital/ballistic transport has been downright common for decades. The question isn't whether you could launch such a thing, or how long it would take, but rather the cost of propelling such a thing (and the willingness of anyplace to have an incoming object like this).

    hawk

    • >and the willingness of anyplace to have an incoming object like this

      Given that pretty much the only thing with a similar flight profile is a nuclear-tipped ICBM... yeah, I can see a fair amount of resistance to the idea of filling the sky with suborbital transports with end points located in your highest value civilian targets.

      If the flight path has to end somewhere a detonation (of any kind) is essentially harmless and thus pointless... you're going to be far enough away from populated areas to make th

    • by phayes ( 202222 )

      You're forgetting that there was always a major (technical) choke point: How do you cheaply land and then relaunch. The Space plane proposals in particular died here. Skylon claims that with a few more billions of £ of development money they will be able to but still haven't left the lab.

      Elon has proven that he can consistently land his boosters on a barge. He thinks he can improve that to landing back on the launchpad supports and is betting the BFR development on it.

    • The notion of suborbital/ballistic transport has been downright common for decades.

      Yup! There have been lots of attempts
      X-30 [wikipedia.org]
      X-43 [wikipedia.org]
      X-51 [wikipedia.org]

      This just takes a slightly different approach. Rather than making a "space plane" that breaths air and lands like a plane, it takes a spaceship and lands it like a helicopter.

  • The fuel/exhaust that a rocket uses and produces isn't exactly the cleanest or safest stuff on earth. I can't imagine people putting up with this stuff being produced on a daily (hourly) basis just outside of their city.

    • by starless ( 60879 )

      The fuel/exhaust that a rocket uses and produces isn't exactly the cleanest or safest stuff on earth.

      Methane and oxygen should be pretty clean...
      (well, some sources of methane are not so nice, but I doubt he'll use those).
      And I believe the production should be based on solar-power produced electricity.

    • by haruchai ( 17472 )

      The fuel/exhaust that a rocket uses and produces isn't exactly the cleanest or safest stuff on earth. I can't imagine people putting up with this stuff being produced on a daily (hourly) basis just outside of their city.

      The plan is for the BFR to use methalox fuel

      From Reddit -
      Methalox (which is shorthand for Methane + Liquid Oxygen) is a superior propellant choice to Kerolox (Kerosene + LOX) for several reasons. Most importantly, it offers higher specific impulse, does not "coke" (ie, deposit unburnt carbon chains everywhere, fouling up your engine), and has similar (80-85%) density to Kerolox. Hydrolox (Hydrogen + LOX) offers better Isp and less coking still, but it has other downsides such as a super low boiling temperat

  • 30min trip, 3 hour security...

    Also only for the extremely rich I'd reckon.

    Though it does remind me of that Simpsons episode...
    https://en.wikipedia.org/wiki/... [wikipedia.org]

  • Hypersonic planes, with sub orbital trajectories reaching anywhere in the world in 45 minutes, have been printed so often in Popular Mechanics, even Ronald Regan talked about it.

    Rate at which Musk is going, that mag is going to change its name to Popular Muskonics.

  • by kencurry ( 471519 ) on Friday September 29, 2017 @01:13PM (#55278579)
    If you can afford direct flights in business class, good hotels, taxi or Uber instead of public trans, can get TSA or global traveller etc., long distance travel isn't that bad. If you can't afford that stuff, then travel does kind of suck and cutting it short as possible sounds good. But in that case you won't be able to afford it either.
  • by nukenerd ( 172703 ) on Friday September 29, 2017 @02:05PM (#55279049)

    So now it's rockets. What happened to Hyperloop?

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