back to article Elon Musk says Harry Potter and Bob the Builder will get SpaceX flying to Mars

SpaceX, Tesla and Boring Company CEO Elon Musk has suggested Bob the Builder and Harry Potter will help his space exploration efforts. In a Reddit Ask Me Anything session dedicated to the Big F**cking Rocket, but which quickly veered into discussion of the Big F**cking Spaceship (BFS) he plans to fly to Mars, the magnate …

  1. MJI Silver badge

    I am now sat at work humming

    Bob the Builder.

    Was a really good show in its time, and the chart hits were fun.

    1. Anonymous Coward
      Anonymous Coward

      Re: I am now sat at work humming

      Was a really good show in its time

      The original stop frame animation was. The newer CGI version is shit.

      1. MJI Silver badge

        Re: I am now sat at work humming

        There is no CGI BtB and Bob is always and forever be Neil Morrisey.

        1. Simon Harris Silver badge

          Re: I am now sat at work humming

          "There is no CGI BtB"

          I assume you mean this in the same way as "there were no sequels to The Matrix".

          Bobnotes:

          There was a CGIed Bob The Builder spin-off - Ready, Steady, Build!, and a poorly received 2015 CGI series of Bob The Builder on Channel 5 (and now moved to some obscure children's channel).

          1. MJI Silver badge

            Re: I am now sat at work humming

            Yes Matrix was standalone

      2. Martin an gof Silver badge

        Re: I am now sat at work humming

        The original stop frame animation was. The newer CGI version is shit

        You could say much the same about Thomas the Tank Engine, yes I know the first few series weren't "stop frame"...

        M.

        1. Sorry that handle is already taken. Silver badge

          Re: I am now sat at work humming

          There is even a modern CGI version of Thunderbirds, although the idea was the original creator's.

          However, if they do a CGI version of The Trap Door...

          1. K.o.R

            Re: weighs 45 pounds

            I actually quite enjoyed the new Thunderbirds, but I have to say the half-hour timeslot really hurt it. Everything was a bit to frantic to get the story completed.

            I loved the way they made the ships believeable with little details like manouevring jets, warning labels, etc.

  2. Mikel

    You could tell he was having fun

    There was a lot of interesting information. Much of which will be obsoleted.

    Down in the comments though... one girl Really wants to go to Venus.

    1. Anonymous Coward
      Anonymous Coward

      Re: You could tell he was having fun

      She probably wants to meet Bananarama.

      1. Aladdin Sane Silver badge

        Re: one girl Really wants to go to Venus.

        Is that a nightflight?

    2. Teiwaz Silver badge

      Re: You could tell he was having fun

      Down in the comments though... one girl Really wants to go to Venus.

      Carson Napier fan?

      (Carson is to Venus what John Carter is to Mars).

  3. Anonymous Coward
    Anonymous Coward

    "Asked how the internet could be extended to Mars"

    ... doesn't need to reinvent everything. I seem to recall from long distant USENET days that there was an RFC that proposed extending the DNS system to add a level of planet codes above the rxisttingcountry code TLDs (with also providion for having 2nd level doamins for under planets for moons). Idea was a system had a domain rooted in the planet where it was or was in orbit around along with duscissuion of rules for handling craft that either travelled between planets or never orbited or landed on planets/moons.

    In the past I've tried to find this (mainly to confirm my memory is still working!) but haven - its was sometime in the mid 80s and was probably issued at the beginning of April!

    1. Elmer Phud Silver badge
    2. Anonymous Coward Silver badge
      Linux

      I see an extension to RFC 6214 to add winged space suits

    3. Charles 9 Silver badge

      I think the big issue will be dealing with variable but LONG times of flight. No real time stuff possible between planets, so things have to be taken into consideration.

      1. MrXavia

        Indeed, 22 minutes each way, meaning 44+ minutes flight time, you don't want to be wasting bandwidth with such high latency.

      2. JetSetJim Silver badge
        Boffin

        I'm sure all you need to do is adapt RFC2549

    4. hammarbtyp Silver badge

      To be honest there is no need to re-invent the wheel. While TCP/UDP can be the transport mechanism while on the ground, when you transmit it over space you will need a different protocol. Firstly it makes sense to extensively use forward error correction to reduce the need to resend packets. Secondly use dynamic compression techniques to reduce the data based on the content. For example voice and images can be greatly reduced based on the level of quality that is acceptable, while data less so.

      To be honest GSM/CDMA use a variety of these techniques to solve similar issues i.e variable quality transport medium and relative low bandwidth. Going back even further X.25 solved many of the same issues to allow data to be sent via plain old telephones(ask your parents about modems kids).

      I'm sure satellite and space agencies have already pretty well got this covered. The bigger issue is maintaining a line of sight connection between Earth and Mars. If we had a constellation of MASER satellites at Lagrange points, we could probably ensure high levels of data integrity and reasonable bandwidth. Nothing is going to help you on the packet delays however

      1. Jellied Eel Silver badge

        TCP/IP is NOT a transport mechanism!

        A long time ago, in a galaxy far far away, there was Vint Cerf, and WorldCom. And a vision for an 'Interplanetary Internet', to expand certain vendor's support contracts. CCIE's needed, must have own transport, and ideally love the tang that perchlorates add to a smoothie. Meetings were held to explore how to conquer things like how to conquer TCP's window & LFP issues, and the rocket scientists kept trying to point to their perfectly good protocols as used in various manned & unmanned missions that travelled far beyond the realms of any digitised cat pics.

        So there are perfectly good protocols already in use by probe designers that communicate waaay more reliably and efficiently than TCP/IP. But pointing that out meant not being invited back to the workshops, which were quite fascinating. It's a variation on the age-old Bellheads v Netheads arguments that often derive from RFC791-

        The internet protocol does not provide a reliable communication facility. There are no acknowledgments either end-to-end or hop-by-hop. There is no error control for data, only a header checksum. There are no retransmissions. There is no flow control.

        And despite transitions from DARPA to IETF and 36yrs of kludges and jollies.. The Internet still relies on a reliable transmission layer. But Vint Cerf moved on to Google, so it'll probably be Alphabets in space, where no-one can hear netheads scream..

    5. macjules Silver badge
      Paris Hilton

      Given his boasting about his profits from BitCoin I have just taken the opportunity to sign up Julian Assange for a one-way ticket to Mars. Mr Musk assures me that as Mr Assange has spent a number of years in seclusion he would be ideal for the first mission, as he has already undergone training.

      He is also sure that they can cancel any Intergalactic Arrest Warrant in the event that 1) We actually discover life on Mars and 2) Julian Assange attempts to have sexual relations with it.

    6. Mike Richards Silver badge

      Surely anyone who has used BT Infinity can tell us what low-bandwidth, high-ping time two-way communications is like?

    7. Anonymous Coward
      Anonymous Coward

      RFC 4838 is probably the best starting place: "Delay tolerant network architecture - This document describes an architecture for delay-tolerant and disruption-tolerant networks, and is an evolution of the architecture originally designed for the Interplanetary Internet"

    8. Robert Heffernan

      This one is easy

      The delay will be just too damn long for anything. The only solution will be a Mars-Local instance of the internet where sync to/from the Earth is done over the currently proposed store-and-forward interplanetary data link.

      I think i'll be off so start developing a Cloud company developing extremely high capability but extremely low weight data center modules based on an aluminium shipping container.

      1. Jellied Eel Silver badge

        Re: This one is easy

        But there are still important questions to be addressed. Like who gets to control and allocate IP addresses for/on Mars? Or how much of the Internet to take with them. If there's space/mass constraints then priority would probably be lots of textbooks. Which thanks to technology is fairly straightforward, ie books on how to build/fix pretty much everything can be stuck on a flash card or Kindle. Then it's just a matter of building stuff, and surviving while you do that.

        I think it'd be better to stage everything, ie first establish orbital or lunar fabrication plants. NASA did some neat stuff with lunarcrete, so freighting construction and components from Moon to Mars could be done using concrete spaceships. Then there's the potential to do some asteroid mining to get more raw materials. The economics of that don't really add up for delivering to Earth, but for interplanetary economics, it'd avoid hauling mass out of our gravity well. So maybe launch a semiconductor fab plant to the Moon or orbit, then they could be stuck into lunar or marscrete datacentres.

        That kind of staging could also feed into data shipping.. Diageo and some other corporates used to ship data on Concord because that was much cheaper than transatlantic capacity, and quick enough for their needs. So bulk data could be ferried the same way & leave interplanetary links for critical communications.

        Musk's plans are.. Ambitious, but it's nice to see someone trying :)

  4. Milton Silver badge

    But it's a lousy analogy, Elon

    "A rough analogy is that we are trying to build the equivalent of the transcontinental railway."

    Unless the transcontinental railway was required to transport, on its very first trip, all the infrastructure, tooling, factories and starter material to build *another* railway for the return trip, then no, there is very little similarity. In fact it's an analogy so useless as to be dangerous—which is the mistake people have been making about interplanetary travel since Tsiolkovsky's first wet dream.

    The problems of huge distances, utterly hostile and completely unforgiving environment, enormous chemical rocket energies requiring bleeding-edge engineering with limited contingencies, simply monstrous energies required to transport pitifully tiny payloads ... even managing a local bus-stop 240,000 miles to the lo-gee Moon for a few days required the resources of the world's wealthiest nation state. Mars is exponentially harder and much, much more dangerous because of its distance *and* the fact that this varies so much. Rescue is not an option.

    I'd love to see proper off-world operations, interplanetary exploration, asteroid mining (Lagrange habitats even), and and all the rest that's needed to get our eggs out of this one fragile basket that we are destroying so fast—but the use of rockets for the heavy lifting seems like such a dead end. Even partly reusable ones.

    With a five-year international effort costing (adjusted dollars) less than Apollo, we could launch 20,000 tonne Orion-style nuclear ships and put enough mass and people onto Mars and the Moon to have instant colonies big enough to have a chance of long-term survival and actually be useful. Warheads can be made clean enough that there wouldn't even be any particular fallout risk on Earth. Perhaps instead of faffing about with glorified fireworks, we should be serious, use the technology that's just been lying around, and just Get Out There at last?

    1. Muscleguy Silver badge

      Re: But it's a lousy analogy, Elon

      And rescue was possible for the lunar astronauts? It took so long to prep an Apollo rocket for launch they would have run out of oxygen before it got there. If memory serves it took them roughly 3 days to get to lunar orbit.

      Mars is a bit easier since as a planet with some sort of atmosphere and more varied terrain than an airless moon there is more sophisticated chemistry and geology available for making stuff out of.

      The problem is that not having a mass of Mars stuff to pay with in advance developing the tech to utilise Mars stuff is going to be VERY difficult even though we have lots of data from the rovers. The killer in good enough industrial processes is what look like minor impurities.

      Sometimes they can be good, like the titanium which contaminates the ironsands NZ Steel turns into steel. Periodically they have to scrape the titanium out of their iron furnace. But they actually make more dollars exporting the titanium than producing virgin steel for the domestic market. But it took a LONG time to develop the techniques to utilise ironsands involving experts and experiments in both the UK and Germany.

    2. Brangdon

      Re: But it's a lousy analogy, Elon

      > transport, on its very first trip, all the infrastructure

      It doesn't have to do all that on its very first trip. There will be several ships used to test entry, descent and landing, and these will bring cargo which will help found the Mars based. Part of the point of Mars is that it has resources in situ from which fuel and oxidiser can be made. It's certainly a challenging project. Musk's point here is that he knows he can't do it alone.

      > Mars is exponentially harder

      It really isn't. The Moon is harder because it has no atmosphere, nights that are 14 days long, lower gravity, less water and generally fewer other resources. There's a reason for picking Mars over the Moon. Musk knows the Moon is there.

      > Even partly reusable ones

      BFR will be completely reusable for most uses.

      > Orion-style nuclear ships

      Well yes; but now you are talking fantasy that won't happen for the foreseeable future. BFR has a real chance of happening within the next decade.

      1. Pascal Monett Silver badge

        Re: "The Moon is harder because it has no atmosphere"

        Having an atmosphere is not going to make Mars any easier. Yes, it does have one, but a thin one. It is not, however, a breathable atmosphere. As such, I fail to see just how that makes things any easier.

        On Mars or on the Moon, a hole in your suit means you die if you can't get to safety quick enough.

        On either, you're lacking running water and have to extract it from the soil. On either, you have dust that will get into everything (okay, bonus for Mars on that one because Moon dust is extremely abrasive).

        Nope, can't see that Mars is any easier to colonize than the Moon.

        And it's a lot farther away (given current technology).

        1. ChrisC

          Re: "The Moon is harder because it has no atmosphere"

          Wouldn't the mere fact that there is at least *some* atmosphere on the Mars-side of your suit/vehicle/etc, compared with the vacuum encountered on the Moon or in orbit, make the design of said suits/vehicles a bit easier thanks to them not needing to cope with such a steep pressure differential?

          1. Chemist

            Re: "The Moon is harder because it has no atmosphere"

            "bit easier thanks to them not needing to cope with such a steep pressure differential?"

            As it's comparing ~1000 millibar Earth to ~6 millibar Mars vs ~1000 millibar Earth to 0 millibar vacuum not a great deal no.

            1. ChrisC

              Re: "The Moon is harder because it has no atmosphere"

              Thanks, I hadn't appreciated just how close to non-existent the Martian atmosphere actually is...

            2. Simon Harris Silver badge

              Re: "The Moon is harder because it has no atmosphere"

              We need a proper name for the mean atmospheric pressure at the surface of the red planet.

              I suggest it is 1 Mars Bar.

          2. Alan Brown Silver badge

            Re: "The Moon is harder because it has no atmosphere"

            Mars suits can be a little easier, but not because of the pressure differential. Ultraviolet light levels are lower due to distance from the sun and the atmosphere is going to prevent most of the micrometeors getting to the surface/slow down the bigger ones somewhat, which means less kevlar is needed.

          3. the spectacularly refined chap

            Re: "The Moon is harder because it has no atmosphere"

            Wouldn't the mere fact that there is at least *some* atmosphere on the Mars-side of your suit/vehicle/etc, compared with the vacuum encountered on the Moon or in orbit, make the design of said suits/vehicles a bit easier thanks to them not needing to cope with such a steep pressure differential?

            The Martian atmospheric pressure is roughly 1% that of Earth, or perhaps 3% of that of a reduced pressure space vehicle. Personally I would not be remotely comfortable in a vehicle so marginal in design that the difference makes any difference whatsoever.

            On the other hand that thin atmosphere is still enough to need a heat shield, but not so great you can land on a sensibly sized parachute. The atmosphere is also held in place by considerably stronger gravity, all things that make getting there in the first place considerably more difficult.

            1. Simon Harris Silver badge

              Re: "The Moon is harder because it has no atmosphere"

              Also gravity on Mars is a little over twice that of the moon (3.7m/s2 vs 1.6 m/s2), so bone loss and muscle wastage might be less on a Mars base than a Moon base, leading to slightly better long term health for Mars residents than Lunar ones.

          4. IT Poser

            Re: "The Moon is harder because it has no atmosphere"

            "Wouldn't the mere fact that there is at least *some* atmosphere on the Mars-side of your suit/vehicle/etc, compared with the vacuum encountered on the Moon or in orbit, make the design of said suits/vehicles a bit easier thanks to them not needing to cope with such a steep pressure differential?"

            Yes. The pressure a suit has to contain is indeed nearly identical for Mars or the Moon, as others have pointed out. This isn't the end of the story though. Any useful pressure suit will leak. On Mars, we can recapture lost gases by compressing the tenuous atmosphere. This isn't possible on the Moon. It's far cheaper to refill our suit by compressing the Martian atmosphere than it is to ship carbon and nitrogen from Earth to the Moon. Economics dictate that the Lunar suit must leak less, therefore more we expect it to be more complex.

        2. Alan Brown Silver badge

          Re: "The Moon is harder because it has no atmosphere"

          "On Mars or on the Moon, a hole in your suit means you die if you can't get to safety quick enough."

          With only 3-5psi in the suit(*) (otherwise the joints are so stiff you'll be sweating like a pig after walking 50 yards), even a bit of cheap duct tape will take care of anything up to 5mm diameter

          (*) Mars atmosphere is so tenuous it may as well be vacuum for this purpose - see James May flying in a U2 for an analogy and even that was denser than martian atmosphere.

        3. Seajay#

          Re: "The Moon is harder because it has no atmosphere"

          The Martian atmosphere helps not because you're going to be able to breathe it directly nor because it makes any real difference to your suit design but because it's a (relatively) straightforward process to make breathable air from Martian air. That means that on Mars you've got four sources of oxygen: tanks you bring with you; recycled exhaled air; made from atmospheric CO2; and made from H2O. Making O2 from CO2 is also something that a pre-positioned machine could do relatively easily without having to crawl around and dig up very slightly damp soil (water concentrations of less than 10^-3) as it would have to on the moon.

          That many separate air systems and most importantly the fact that they will keep going for as long as your solar panels, is what you want if you're planning a permanent presence.

        4. IT Poser

          Re: "Having an atmosphere is not going to make Mars any easier."

          Just because you fail to see how an atmosphere makes things easier doesn't mean that having an atmosphere makes things easier. Here is a very brief list of key advantages.

          Areobraking - The amount of energy needed to send a craft from Earth to land on Mars and the Moon are similar because the Martian bound ship doesn't have to use fuel to cancel orbital velocities.

          Micrometeorite shielding - Specs of dust are an impact hazard on the Moon. The Martian atmosphere eliminates this potential threat.

          Radiation shielding - The Martian atmosphere provides far more than the Lunar lack-of-atmosphere.

          Temperature regulation - The Martian atmosphere traps enough heat that we can deal with the night time cold. Even with a P-238 heating element, the most recent lunar rover began malfunctioning after only one Lunar night. Solar powered robots without a P-238 heating element can survive over a decade on Mars.

          Extractable resources - The Martian atmosphere is an easily processed source of carbon and nitrogen. Virtually all of the chemistry we use involves carbon and nitrogen. A colony will require tons of carbon and nitrogen reserves per person. Based on current knowledge, there are no extracable carbon or nitrogen sources on the Moon.

          The last point is very important. Each colonist will require a carbon reserve of 12+ tonnes for the agrarian sector of the economy. When we start adding other economic sectors, such as textiles, plastics, and metallurgy, the per-colonist reserve necessary grows rapidly. On Mars CO2 capture and recycling doesn't have to be perfect. We can simply compress more atmosphere if we need more carbon. Every loss on the Moon has to be replaced with imports. Capturing the CO2 emmissions from aluminium production is going to add mass and complexity, with necessary higher price tag, of Lunar equipment compared to equipment that does the same job on Mars.

          The only advantage that the Moon has, and this isn't based on current technology, is travel time.

      2. MiguelC Silver badge

        Re: 14 days long nights on the moon?

        Not so: days are endless and nights are endless, it just depends of where on the moon you are. [search for "moon tidal lock" on your favorite google ;)]

        1. DropBear Silver badge
          WTF?

          Re: 14 days long nights on the moon?

          "Not so: days are endless and nights are endless"

          You might want to rethink that a few more times, go ahead, I'll wait...

          Clue: the same face of the moon we always see totally doesn't have things like visible phases isn't it...

          1. MiguelC Silver badge

            Re: 14 days long nights on the moon?

            Yeah.. coffee tank was probably empty :)

        2. the spectacularly refined chap

          Re: 14 days long nights on the moon?

          Not so: days are endless and nights are endless, it just depends of where on the moon you are. [search for "moon tidal lock" on your favorite google ;)]

          Err, no. The moon is tidally locked with respect to the Earth, not the Sun. You only need to look at the moon over the course of a few nights to see that specific points of the surface alternate between day and night as the phase changes.

        3. Alan Brown Silver badge

          Re: 14 days long nights on the moon?

          The position of the earth may be endlessly stable in the Moon's starry sky but there is definitely a 28 (earth) day light/dark cycle.

          1. Charles 9 Silver badge

            Re: 14 days long nights on the moon?

            "The position of the earth may be endlessly stable in the Moon's starry sky but there is definitely a 28 (earth) day light/dark cycle."

            The point is that it's always the same half of the moon getting lit by the sun. If you were on the moon, wherever you stood would either always be lit or always be dark, because its rotation and revolution periods match practically perfectly.

            1. Aladdin Sane Silver badge
              Facepalm

              Re: 14 days long nights on the moon?

              Nope. Same side always faces Earth (give or take a bit of wobble), but the far side of the moon will be illuminated when it is on the day side of Earth, and the near side will be illuminated when it is on the night side of Earth.

            2. John Brown (no body) Silver badge

              Re: 14 days long nights on the moon?

              "The point is that it's always the same half of the moon getting lit by the sun."

              That's twice now. All you have to do is look up in the sky over a few nights and you can see for yourself just how silly that it. Think about it. If there's a "full" moon then the whole of the visible side of the moon is lit by the sun from the front

              Now go look at all the video of the well publicised and reported total eclipse across the USA the other month. Which side of the moon was likely to be illuminated by the Sun while the moon was between the Sun and the Earth?

              You almost sound like a flat earther, or maybe think the Sun orbits the Earth.

    3. John Brown (no body) Silver badge
      Thumb Up

      Re: But it's a lousy analogy, Elon

      "Unless the transcontinental railway was required to transport, on its very first trip, all the infrastructure, tooling, factories and starter material to build *another* railway for the return trip, then no, there is very little similarity."

      I can't upvote this enough. All analogies to Earthly voyages and expeditions fall over as soon as you remember that all space journeys involve taking absolutely everything with you, including the air you breath.

      Building a transcontinental railway, or sailing off to "discover" America, at least you can breath all the way, find local food and water with little or no imported technology and generally have the ability to survive, even if shipwrecked or lost i the wilderness.

      1. AdamWill

        Context

        But you're both completely ignoring the context of the analogy. It wasn't an analogy about the *difficulty* of the task. It was an analogy about the *defined scope* of the task. He was saying that SpaceX's goal is to provide the service that gets people and materials from point A to point B - and not, for instance, to provide shelter and power and so on and so forth at point B. In the way the transcontinental railway companies provided a way to get stuff from coast to coast, but didn't build wells and houses and all the rest of the stuff that was needed for people to actually live there in comfort.

    4. Anonymous Coward
      Anonymous Coward

      Re: But it's a lousy analogy, Elon

      Oi!! Don't point out the obvious fault's with the Master's thoughts!! Don't cha know - he is the true messiah.

  5. Christoph Silver badge

    If he can economically "exceed passenger airline levels of safety", then so can the airlines. But they haven't. So probably either it isn't possible or it isn't economic.

    1. Simon Harris Silver badge

      "exceed passenger airline levels of safety" - could be a severity/mitigation issue - there are less mitigation options in space, so reduce the severity/frequency of incidents beyond what is economical for airlines?

      Airliners* don't tend to end up millions of miles away from somewhere they can make an emergency landing if something goes wrong.

      * Except for RyanAir - they seem to land a million miles away from anywhere you may actually want to get to.

    2. Spudley

      If he can economically "exceed passenger airline levels of safety", then so can the airlines. But they haven't. So probably either it isn't possible or it isn't economic.

      I can see your point and I really do want to agree.

      However, the same could have been argued about dramatically cutting the cost of an orbital launch. Or landing and reusing an orbital rocket. Or building an electric vehicle that competes well with fossil fuelled cars.

      Those industries spent a lot of time making the case that doing those things wasn't possible or economic. SpaceX and Tesla have proved them wrong, and now the rest of the industry is rushing to catch up. The car industry stands a chance of doing so, but the established players in the rocket industry look to be absolutely screwed

      But all that said, Musk's rocket is never going to be a simple drop-in replacement for airlines, no matter how cheap and reliable it gets.

      For starters, flights will involve periods of periods of weightlessness, etc. It does sound like fun, but it won't be suitable for all travellers.

      Also, the noise levels and safety aspects of a rocket launch mean that the launch and landing sites will need to be further away from the city than an airport would be, so there will be additional travel time to factor in which will likely wipe out a lot of the gains over aircraft, particularly for shorter flights.

      I can see it becoming a viable option for very long distance travel, but medium-haul and short-haul journeys will still use traditional aircraft.

    3. Adam 52 Silver badge

      " so can the airlines. But they haven't. So probably either it isn't possible or it isn't economic."

      Not economic. You could build much stronger jet engines better able to contain fire or a blade failure but they'd be heavier, less powerful, more expensive and consume more fuel.

      Similarly you could have a second crew and independent instruments to mitigate the human element, but then you'd lose passenger space and have to pay more wages.

      Or more simply, you could include an AED in the first aid kit for a few hundred pounds. Airlines don't even do that unless forced by a regulator.

      Air travel could be safer, but we've reached a cost/safety sweet spot.

  6. A Non e-mouse Silver badge

    More engines!=more safety

    ...and we have more engines than the typical two of most airliners, then exceeding airline safety should be possible.

    The early attempts at building a vertical take-off & landing aircraft had multiple engines producing thrust. They discovered that having multiple engines did not increase reliability but decreased reliability (and introduced lost more complexity). Hence why the Harrier jet has just one engine.

    If an engine has a failure rate of once every 10,000 hours, one engine out of four will have a failure rate of 1 in 2,500 hours.

    Notice how many of the new jets just tend to have just two engines rather than four (or more)? It's partly about cost, and partly to do with reliability figures. Also note that two engine planes have to be capable of flying with just one engine.

    1. phuzz Silver badge

      Re: More engines!=more safety

      The Harrier was developed in the 1960's. Back then computer control of multiple engines was in it's infancy. Now it's at the stage where SpaceX can regularly land their rockets tail first.

      1. BebopWeBop Silver badge

        Re: More engines!=more safety

        Now it's at the stage where SpaceX can regularly land their rockets tail first.

        You have missed the point and I suspect have never been in a position where a true calculation of risk (aka likelihood of failure combined with subsequent cost) is necessary.

        1. Brangdon

          Re: More engines!=more safety

          The point here is that more engines may mean more failures, but it also mitigates the cost of those failures. With 31 engines, loss of one or two or a few of them should not lead to loss of vehicle, crew and passengers. It's good that an aeroplane can fly on one of its two engines, but even if it loses both, it can glide to a crash-landing and most humans aboard will survive. Not so with a rocket.

    2. BebopWeBop Silver badge

      Re: More engines!=more safety

      For ye downvoters - the arithmetic is quite correct. It also explains why, if you have the capacity, maintaining cooperating processes on a single box make more sense than distributing them (if the process requires all to function). I remember a fine argument (with salespeople of course as to why we should NOT recommend 4 expensive and notionally higher availability servers over a single high availability box).

    3. LDS Silver badge

      Re: More engines!=more safety

      Long range airplanes now have just two engines because reliability and power increased. While it's true that more engines means more risks of one engine failure, it also means there are more engines remaining before you have no engines at all. It's OK to have a "less reliable" system as long as a single fault is not critical. A single engine airplane may be statistically more "reliable" but a single fault is critical - you need to find a landing spot within gliding range, or you're dead. A two engine aircraft may lose speed and altitude, but still have a better chance to find a landing spot.

    4. mosw

      Less engines!=more safety

      Airlines moved to less engines on transatlantic flights because they are cheaper to maintain and operate. To do that they had to prove that a plane could remain aloft with only one engine which with current technology they can. 4 engines is still likely more reliable than 2, but 2 is good enough in this situation.

      For rockets, it will completely depend on the reliability and typical failure mechanism of the specific rocket motor. Determining these characteristics is called engineering. If an individual engine failure is likely to bring down the entire rocket, then less engines is better. However, if single engine failures can be contained so as to allow continued flight, then more engines will likely be more reliable.

  7. John Smith 19 Gold badge
    Unhappy

    ""exceed passenger airline levels of safety""

    Well airliners have had 8 decades to improve their safety record. Aircraft engines operate for 10s of 1000s without removal from their mounts and don't require t/o thrust to exceed GTOW every time. Cooling the turbine blades is also SOP for planes with people on board, and has been for decades. I'm not sure any rocket engine ever has.

    I think Musk will find that level of safety surprisingly difficult.

    BTW It's impressive how Musk's game plan for P2P transport mirrors Reaction Engines certification plans for human rating Skylon.

    1. Jellied Eel Silver badge

      Re: ""exceed passenger airline levels of safety""

      I think liquid cooling is a thing in rocket science, ie using the liquid fuels to help cool the engine. Which given the rather large temperature differentials between cryogenic fuel and exhaust over a short distance and time is one of the reasons for malfunctions of the terminal kind. But anything that uses hypergolic reactants as coolants is something I'd rather watch from a very safe distance.

      1. IT Poser

        Re: ""exceed passenger airline levels of safety""

        Based on what I found scattered throughout the Reddit AMA, the plan is to use methalox, not hypers, for control thrusters. These will be fed by the main fuel and oxidizer tanks using a pressure fed system. Cryo-cooling systems will not be used for the initial BFS flights. Instead boil-off will be controlled by venting.

        Methalox cryo-cooling is a mostly solved problem. Musk acknowledged that it will be added so I expect there volume and mass reserved in the BFS designs to accommodate the system.

      2. This post has been deleted by its author

      3. John Smith 19 Gold badge
        Unhappy

        "I think liquid cooling is a thing in rocket science, "

        The liquid cooling is for the combustion chamber and nozzle.

        AFAIK no rocket turbines (which drive the pumps in most big rocket engines) are cooled. Jet engine turbine blades have been cooled for decades, which is why their operating temperature can be close (and sometimes exceeds) the melting point of the alloys they are made of.

        1. Jellied Eel Silver badge

          Re: "I think liquid cooling is a thing in rocket science, "

          I know it's wiki, but..

          The Space Shuttle Main Engine's turbopumps spun at over 30,000 rpm, delivering 150 lb (68 kg) of liquid hydrogen and 896 lb (406 kg) of liquid oxygen to the engine per second,

          .. it doesn't translate that into NOS shots, even if you could fit one to an LS motor. Which could be a project to trump JATO cars. Or possibly something the Bloodhound crew are doing anyway. Either way, it's still not something I'd want to be strapped to. So still cooled by the cryogenic fuels & having 15+ combustion chambers to feed is going to need some rather careful plumbing & control.

  8. Seajay#

    Colonist motivation

    What's really needed is an economic reason to go. I want to go but it's hard to see how you can get a job on Mars when anything you could do out there could be done much more cheaply here.

    It's not analogous to emigrating to the new world. The new world had huge amounts of fertile land and resources which could be used from year one and be traded back to the old world not long after. Mars doesn't have either of those. It's going to be reliant on earth for a long time.

    So how do you make it worthwhile to go? Maybe by granting anyone who emigrates a large patch of martian land? Even if you do that (which current law doesn't allow) the land is worth nothing for now and will need a huge investment of money and time before it is worth something. That huge cost and huge risk means that the reward needs to be huge^2 to be worthwhile (1000 sq km ? What will that be worth once we've filled up earth?)

    1. A Non e-mouse Silver badge

      Re: Colonist motivation

      What's really needed is an economic reason to go.

      Unfortunately, politicians & financiers don't see "Survival of the human race" as a good use of money.

    2. JetSetJim Silver badge

      Re: Colonist motivation

      > What's really needed is an economic reason to go. I want to go but it's hard to see how you can get a job on Mars when anything you could do out there could be done much more cheaply here.

      Nah - I'd do it for the props, not the money. There are other motivations than currency. Others may do it to avoid nuclear fallout from when General Trump has a hissy-fit and pushes the other red button on his desk (however likely that scenario may or may not be).

      1. BebopWeBop Silver badge

        Re: Colonist motivation

        I would hope that the other red button activates the nurse (or depending on your preference a carefully controlled explosion)

        1. Alan Brown Silver badge

          Re: Colonist motivation

          "I would hope that the other red button activates the nurse"

          You mean like this? https://www.youtube.com/watch?v=0FaH7ATXkWg

    3. Anonymous Coward
      Anonymous Coward

      Re: Colonist motivation

      I think there could be a few economic reasons to go. The first few people that go would have a fairly good chance of becoming a YouTube star. There are a few vloggers that make a living from YT advertising, product placement etc. The idea of low-gravity sports as been floated (!) as a way to generate TV revenue. I can imagine universities would be happy to sponsor geologists, etc, to travel there to do science. Also producing zero-G porn on the journies. VC's looking to get in early with patents and business that would stand a good chance of being very successful once the 'Mars Economy' does take off.

      In summary I think the economic reasons are there - it's just a bit too far away for many to be believable. But I think if/when SpaceX do start landing space-trucks full of stuff on the Martian surface you see the Mars industry and economy explode.

      1. John Brown (no body) Silver badge

        Re: Colonist motivation

        "VC's looking to get in early with patents and business that would stand a good chance of being very successful once the 'Mars Economy' does take off."

        That sounds a bit like investing a new Oak tree plantation. Something you do for your children or grandchildren rather than for yourself. Most VC don't seem the type to plan or even think that far ahead.

    4. Pascal Monett Silver badge

      Re: Colonist motivation

      "What's really needed is an economic reason to go"

      Nonsense. Humans do not care about economics, otherwise our global economy would be in quite a different state. There are people who are willing to go simply to be there, on another planet, and damn the cost.

      Heck, there are any number of valid reasons to go :

      - hipsterism (you lamers are still back on Earth, pah!)

      - get away from the in-laws (okay, it's expensive, but it's foolproof)

      - see a Martian sunrise

      - die on a different planet than the one you were born on

      - have a job (those buildings aren't going to erect themselves)

      - be able to call oneself a space colonist

      I'm sure you can find lots of other equally valid reasons from the human point of view.

      As such, any company that can offer the trip is sure to have hundreds, if not thousands of customers lining up at the launch pad, begging to have their cash accepted. All any company has to do is make sure that it can actually survive financially and economically feasible is done.

      Especially since you're not getting any right to complain if the trip isn't perfect - because you'll be dead.

      1. Seajay#

        Re: Colonist motivation

        I would absolutely go just for the journey.

        The problem is that while I might conceivably be able to get my hands on the $500k ticket price by liquidating my whole earth life and working my arse off while living in a shoebox for few years (mining jobs in some particularly unpleasant part of Africa seems like the obvious option) there is no way I could subsequently support myself on Mars eating food brought from earth at many million dollars per tonne and breathing air made by expensive machines also brought from earth, consuming spares also brought from earth.

        So I need a way to generate money. It's not possible to live only by doing things like erecting buildings on Mars because that work only has value to other people on Mars. For the Mars colony to be economically viable, it needs to be generating value for people on earth similar to the cost of sending us expensive stuff in expensive rockets. It's almost impossible to imagine mars actually exporting anything so incredibly valuable that even after transport costs it can pay for all of that.

        So the best option seems to be to export something massless like property rights. I move to Mars and get my large parcel of land. I give half of that to Mars Corp in exchange for agreeing to send me 20 years of resupply rockets (by which point hopefully the martian mines and factories are working and we're self sustaining). People on earth buy shares in Mars Corp because they know that in the long term it will own half a planet and that must be worth a lot.

        1. This post has been deleted by its author

        2. John Smith 19 Gold badge
          Unhappy

          "For..Mars colony to be economically viable, it needs to be generating value for people on earth "

          You have (literally) no idea how difficult it is to get that (apparently) simple idea across to Musk fanbois.

          Technically you could work in the settlement ("colony" has very negative connotations for large parts of the world :-( ) and be paid in "Musk Credits" (BTW I'd expect food growing to be ramped up pretty early on) and that's find for the settlers.

          But you're right. the problem is what is used to buy the stuff in from Earth that cannot be made in the settlement.

          Some people have suggested some kind of "Billionaires trust fund" to support the settlers, or sponsorship arrangement ("This month Kevin learned to clean and maintain the air filtration units. In his spare time he has been completing his EMT training")

          But my instinct is it will be mostly supporting the residents of "Musk Villas," so you'd probably be best off learning how to change adult nappies and catheterize old codgers.

          Welcome to Mars.

    5. John Smith 19 Gold badge
      Unhappy

      "It's not analogous to emigrating to the new world. "

      Correct. People went to the "New World" and made a shed load of money growing or catching stuff there and sending it back home (wherever "home" happened to be). That's almost a non starter.

      The only thing that's close to that would be products that are made on Mars specifically to carry the "Made on Mars" logo ("Glacier water with a hint of peroxides." US bottled water is about a $14Bn industry. Yes really)

      Super high isolation medical laboratories might be a possible option, if you can get the samples there (or synthesis them on site) safely. But my favorite long term sustainable option is....

      "Musk Villas. Luxurious Low Gravity Living for the extraordinarily well off"

    6. nijam

      Re: Colonist motivation

      > What's really needed is an economic reason to go.

      Well, economics is really about the movement of money (resources, economists might like to say, I suppose, but really it's just money they're talking about). No money is being taken to Mars at this stage, funding is being spent here on earth. So in pure economic terms, any benefit from going to Mars is extra to the pure economic benefit of earth-based spending (on e.g. rocket scientists salaries).

      1. Seajay#

        Re: Colonist motivation

        Well, economics is really about the movement of money (resources, economists might like to say, I suppose, but really it's just money they're talking about).

        It absolutely isn't about the movement of money and it very very much is about the movement of resources, enormously expensive resources which need to be moved at a vast cost of even more resources. It's no good moving a derivatives contract for an atmospheric regulator to Mars, you need the actual machine there, or you can't breathe. Someone on earth needs to have made that machine and someone needs to have provided them with the raw materials to do so. Who is that person paying the manufacturer? paying for the rocket fuel? paying for the raw materials? and why are they paying out so much when they're getting nothing from Mars?

    7. allthecoolshortnamesweretaken Silver badge

      Re: Colonist motivation

      It's there.

      That's all the motivation humans used to need to go somewhere for the first time.

      1. John Smith 19 Gold badge
        Unhappy

        It's there. That's all the motivation humans used to need to go somewhere

        Of course they could either build their own transport or walk "there" wherever it happened to be.

        And expedition <> settlement.

  9. Simon Harris Silver badge

    In the spirit of the BFR...

    will they now be

    Harry Fucking Potter and Bob The Fucking Builder?

    (maybe for parents who have been overloaded by these characters, this has always been the case).

    1. Flocke Kroes Silver badge

      Re: In the spirit of the BFR...

      When BFR became the official name I assumed it would be backronymed with a minced oath like Flaming. As it uses methane, Farting is a viable choice. The official politically correct backronym uses Falcon, but that could change... After a quick web search I found someone has already called Ajit Pai a falcon idiot. So far there are no falcon twits or falcon morons but I am sure commentards somewhere will fill the vacuum.

      1. Simon Harris Silver badge

        Re: In the spirit of the BFR...

        They could have used Battlestar Galactica language and called it a Big Fracking Rocket, but that wouldn't go down well with environmentalists.

        1. nijam

          Re: In the spirit of the BFR...

          > ... that wouldn't go down well with environmentalists.

          Nothing does, so choose what you prefer and ignore them.

      2. Spudley

        Re: In the spirit of the BFR...

        When BFR became the official name I assumed it would be backronymed with a minced oath like Flaming

        I figure all he has to do is paint a giant letter "F" on the inside of the thing, and he can say it's a "Big F in Rocket".

        1. Alan Brown Silver badge

          Re: In the spirit of the BFR...

          "I figure all he has to do is paint a giant letter "F" on the inside of the thing, and he can say it's a "Big F in Rocket"."

          That, or get Love Honey to sponsor one.

          1. Dave 126 Silver badge

            Re: In the spirit of the BFR...

            Malcolm Tucker: And do it ASAFP!

            Spad: What does the F stand for?

            Civil servant: 'Feasibly' I assume.

      3. Alan Brown Silver badge

        Re: In the spirit of the BFR...

        It's the best falcon rocket in the falcon business!

        Who needs fracking, flaming farting or other choices? It even sounds "almost" right.

  10. Prosthetic Conscience
    Paris Hilton

    Oof deep throttling

    She knows ->

  11. Anonymous Coward
    Anonymous Coward

    Dangerous

    Elite players know better than to trust CMDR Harry Potter with something

  12. sabba

    Personally, I'd rather we stay away from other planets...

    ...at least until such time as we have developed some sense of environmental (and social) responsilbility and stopped trying our best to destroy our current one. It seems to be that we are very much like those people who head out to enjoy the countryside complete with a bag full of delicious snacks. The wrappers for which they then proceed to litter over that pristine wilderness.

  13. John Smith 19 Gold badge
    Unhappy

    "Re: Colonist motivation "

    Quite a lot of those reasons people have suggested are

    a) More of a holiday event, rather than a reason to stay on Mars forever. It's a least a 90 day trip there.

    b) A lot of these are likely to be short term viable, until the next "Next big thing" comes along.

    That's not exactly a viable business plan, is it?

    1. annodomini2

      Re: "Colonist motivation "

      Given its a 2-3yr round trip with current tech, probably with a lot of work in between, I doubt it would be classed as a holiday.

  14. Anonymous Coward
    Anonymous Coward

    will get SpaceX flying to Mars

    And Model 3s flying off the assembly line.

  15. allthecoolshortnamesweretaken Silver badge

    I'd say that the Moon is harder to colonise because of the regolith/dust. That stuff is awful.

  16. John Smith 19 Gold badge
    Unhappy

    "I'd say that the Moon is harder to colonise because of the regolith/dust. That stuff is awful."

    Mars dust is not much (if any) better. It's got superoxides (like scouring powder), is pretty fine so an inhalation hazard and potentially as dangerous as Asbestos.

    Keeping dust out of the settlement, and neutralizing it's effects of it when it does get in, is going to be a fairly important task.

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