23 ms·

The SpaceX Starship is a big deal

432 points by mrfusion 7y ago

carrozo 7y ago
Starship is a cargo conveyor system. The Starship is comparable in complexity to a 737, and so it’s not unthinkable to have a construction rate of 500/year. If each Starship manages 300 flights per year, each carrying 150 T of cargo, then we are talking a yearly incremental cargo capacity growth of 22 million tonnes to orbit. At this point, the most meaningful constraint on launch capacity might be launch pad construction rate. This made me think of this shot in Star Trek: Into Darkness https://scifi.stackexchange.com/questions/127311/why-is-a-model-of-the-secret-starship-in-plain-view https://scifi.stackexchange.com/questions/127311/why-is-a-mo...
- gameswithgo 7y ago
  why?
  - carrozo 7y ago
    It's that tracking shot where it starts with spaceships we're familiar with in our own "timeline" like the Space Shuttle and works up to larger and larger vessels, including Enterprise. Suppose having the ability to ferry more and more cargo to low earth orbit means we can start creating much larger structures in space?
bryanlarsen 7y ago
> With an eventual flight rate of once per day per Starship, Gwynne Shotwell said that their business plan for using Starship to compete with long-distance airliners involved making about a dozen trips per day per Starship.
- avmich 7y ago
  > about a dozen trips per day per Starship Gagarin flew for around 108 minutes, so orbital velocity allows longest trip between two points on Earth in about 54 minutes. Shorter trips could be less, but liftoff-landing take roughly a fixed amount of time. Twelve trips per day is 2 hours per trip. Taking 40 minutes of flight, there are 1 hour 20 minutes to get onboard, to get off board, to handle luggage (if needed?), to refuel and check systems. Wonder how does it look from airlines operation prospective.
  - madaxe_again 7y ago
    That stands pretty much parallel with aviation turnarounds - it’s purely logistics. If they don’t need to do any maintenance other than standardised checklists between flights, which is their ambition, there’s no fundamental reason they couldn’t do this.
  - deadbunny 7y ago
    A (very) cursory search turned up this[1], which suggests they can turn around what appears to be a relatively short haul aircraft in ~50 mins arrival to departure. My uneducated guess would be that refueling of a starship alone is likely to take a long time if you're pumping in 1,200 tons of fuel. 1. https://your.heathrow.com/happens-aircraft-turn-around-british-airways/ https://your.heathrow.com/happens-aircraft-turn-around-briti...
  - Consultant32452 7y ago
    Do all orbital flights take off in the same direction due to the rotation of the Earth?
    - gpm 7y ago
      "Most" would be more accurate. Flights that want to orbit over the poles take off aiming perpendicular to the rotation instead. A few satellites have been launched backwards intentionally.
      - isostatic 7y ago
        I think sun synchronous orbits are retrograde P2P sub orbital hops are either direction, 30-40 minutes, maybe 25 for shorter trips like London to New York.
        gpm 7y ago
        Agreed that P2P sub orbital hops are any direction. Low sun synchronous orbits are approximately the same as polar oribts, more perpendicular than retrograde. I'm not sure if we use high sun synchronous orbits for anything?
- gameswithgo 7y ago
  I wonder if anyone with sufficient experience in rockets could comment on whether that idea is at all plausible.
  - chasd00 7y ago
    i have no experience but, man, it would be so freaking noisy. where would they take off and land?
    - donkeyd 7y ago
      Yup, that's the big issue. Being able to fly London to NY in 30 minutes is great, but the landing/launch sites will have to be pretty far from the cities to have the sonic booms not break windows all the time. That increases total travel time.
      - ralusek 7y ago
        And then you can just travel through Boring tunnels.
      - deadbunny 7y ago
        Some routes would definitely be worth it. Opposite sides of the world would become connected like never before. If I could catch a "flight" to Australia (from the UK) in the time it takes to fly to New York it would be game changing. Hell even 4 hours to LA would be preferable to the 11 hour flight time + 2 hours either side it takes now.
        jandrese 7y ago
        But would you be willing to pay 10x or 20x the cost of a "slow" conventional airline ticket for it? The fuel costs may be low by space launch standards, but they'll be huge by commercial airline standards.
        bryanlarsen 7y ago
- DennisP 7y ago
  And in his recent big presentation, Musk said they hoped to ultimately reach three daily flights to orbit for each Starship, and thirty per day for each first stage. He said at that rate, with ten Starships they would have a thousand times the launch capacity of the entire world right now including Falcon 9/Heavy.
- tbabb 7y ago
  This is not happening soon. Safety/redundancy of rockets (including SpaceX's) compared to airliners is abysmal—about five orders of magnitude worse. With passenger manifests in the hundreds (necessary for the economics to work), and with any failure being catastrophic, you'll be seeing multiple Tenerife disasters [1] per year. You also can't launch a rocket (especially one that big) anywhere near a major city for sound and safety reasons, which means at best you are building an offshore spaceport, which is terrible for the logistics and economics. But that's still nothing compared to the safety problem. [1] https://en.m.wikipedia.org/wiki/Tenerife_airport_disaster https://en.m.wikipedia.org/wiki/Tenerife_airport_disaster
  - randyrand 7y ago
    When does startship need to light its engines on landing? What about landing in a 2000 foot deep hole in the ground?
    - tbabb 7y ago
      I don't follow. What's the hole for?
      - jandrese 7y ago
        Presumably to let it hold off on lighting the engines until it is below the surface of the Earth, to avoid radiating the sound outward.
        tbabb 7y ago
        Setting aside the economic infeasibility of a 2000 foot hole, the rocket's gonna have to fly out of it at some point.
  - londons_explore 7y ago
    The sound reasons could potentially be mitigated by launching behind a wall, acting as a sound reflector right? Humans can build walls 1km high or more without much difficulty, and by the time the rocket is 1km up, it is already moving pretty fast, and is already much further away.
chasd00 7y ago
to me, it's the Raptor engine that is the big deal. And within the Raptor, it's the alloy developed on the oxidizer side pre-burner that's the big deal. I wish i could have been there the moment that alloy was conceived and the moment it past the first round of testing. I would have poured so much tequila it would have had a budget impact.
- serioussecurity 7y ago
  Tell me more.
  - chasd00 7y ago
    "So, SpaceX developed their own superalloy in house that they named SX500. According to Elon, it’s capable of over 800 bar of hot oxygen-rich gas. That may have been one of the biggest hurdles in developing the Raptor engine." almost halfway down, the article is long but so well worth the time. https://everydayastronaut.com/raptor-engine/ https://everydayastronaut.com/raptor-engine/
    - wolfram74 7y ago
      The reason "over 800 bar of hot oxygen-rich gas" is a high hurdle to break is the propensity for a metal to rust and become useless is proportional to the pressure (concentration) of the oxidizer (oxygen) it's surrounded in and how hot it is. So this metal is able to withstand 800 bar (1 bar ~=1 atmosphere), or 4 thousand times as much oxygen as sea level, at quite elevated temperatures. This is a hellish environment to not just immediately combust in.
      - Tuna-Fish 7y ago
        And note that at 800 bars of hot oxygen, metal doesn't so much rust as it burns with a bright flame. The environment in the Raptor oxy-rich preburner is much worse than the typical oxyacetylene torch that is used to cut steel.
- Robotbeat 7y ago
deleted 7y ago
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PaulHoule 7y ago
The lunar mission profiled in there takes 15 tanker launches, which is a lot. As for in-situ resource utilization, how about this: Apollo astronauts found nearly 40% iron ore in some areas of lunar regolith. That may be unusually high, but you can do magnetic separation, then pass hydrogen gas through the ore to get iron and water. Crack the water molecules, recycle the hydrogen, and then use the oxygen to refuel "starships", where it accounts for 4/5 of the propellant mass. In the meantime you get iron by the hundreds of tons on La Luna that you can use to make pressure tanks to store that oxygen, live in, etc. (It's been a long trope in sci-fi and speculation that a lunar economy would be an aluminium economy, and that people who seek iron will go for the asteroids, but it is very easy to get iron + oxygen as described on the moon, it is much harder to reduce other common metals on the moon.) Here is the mass driver that Gerard K. O'Neill told you about, available off the shelf: https://www.youtube.com/watch?v=58MmOpSm4LY https://www.youtube.com/watch?v=58MmOpSm4LY That can send a 10kg projectile at 2.5 km/s which can get to the Earth-Moon L1 or L2 points. If you can increase the velocity to 3.1 km/s you could graze the Earth's atmosphere and deliver oxygen and other materials to LEO. Either way you need something that can soak up excess momentum at the end, but you could greatly reduce the need for tanker launches.
- bryanlarsen 7y ago
  > The lunar mission profiled in there takes 15 tanker launches, which is a lot. Using pre-Starship capabilities, 15 launches is a lot. At $5M/launch, 3 launches per day that they're forecasting for Startship, 15 launches would be a tiny part of the budget.
- whatshisface 7y ago
  Pure iron is a poor material. You would want some carbon to turn it in to steel, and that would have to come from another process.
  - PaulHoule 7y ago
    If your space economy is driven my methane (e.g. the Starship fuel) you could ship methane to the moon, separate the carbon from the hydrogen, recycle the hydrogen and mix the carbon in with the iron. Mild steel might have 0.1% carbon so you get a multiplication ratio in the 100's. The main trouble is you also want to build up a carbon stock for biological applications... But it is the nitrogen stock that I haven't figured out.
avmich 7y ago
> If each Starship manages 300 flights per year, each carrying 150 T of cargo, then we are talking a yearly incremental cargo capacity growth of 22 million tonnes to orbit. https://en.wikipedia.org/wiki/Space_sunshade https://en.wikipedia.org/wiki/Space_sunshade > One proposed sunshade would be composed of 16 trillion small disks at the Sun-Earth L1 Lagrangian point, 1.5 million kilometers above Earth. Each disk is proposed to have a 0.6-meter diameter and a thickness of about 5 micrometers. The mass of each disk would be about a gram, adding up to a total of almost 20 million tonnes.[3] Such a group of small sunshades that blocks 2% of the sunlight, deflecting it off into space, would be enough to halt global warming, giving us ample time to cut our emissions back on earth.
- deleted 7y ago
  [deleted]
- 7777fps 7y ago
  And if that works, and we restore a more normal cycle, how do we avert the next ice-age with all that space junk?
  - xur17 7y ago
    We remove it?
  - _ph_ 7y ago
    If it isn't automatic the case, the material for the discs could be designed such that it dissolves in the normal solar radiation after a decade or so.
    - beerandt 7y ago
      Can't dissolve without a solvent.
      - avmich 7y ago
        Do you know what happened to USA flags which astronauts installed on the Moon?
Tepix 7y ago
I wonder if we will revive O'Neill's idea of putting a mass driver on the Moon. That would potentially enable getting mass (like water or lunar regolith) into space (alas from the Moon, not Earth) at even lower cost than Starship. Recommended related link: http://ssi.org/ssi-supermodels-part-2-make-your-own-ssi-mass-driver/ http://ssi.org/ssi-supermodels-part-2-make-your-own-ssi-mass...
- wolfram74 7y ago
  This paper [1] estimated a mildly useful launcher could be delivered to the moon with no in-situ production for 9 falcon heavy launches, or half of a nominal starship payload. [1] https://www.researchgate.net/publication/276039810_Mass_Estimate_for_a_Lunar_Resource_Launcher_Based_on_Existing_Terrestrial_Electromagnetic_Launchers https://www.researchgate.net/publication/276039810_Mass_Esti...
- skykooler 7y ago
  The big limitation for constructing something like that is setting up a manufacturing industry on the Moon: even with Starship, a mass driver requires far more processed material (mainly refined metals) than can be practically shipped up from Earth. The tipping point for a Lunar mass driver will be when we've created enough of an industry on the Moon to construct it out of local materials.
  - wolfram74 7y ago
    Obviously complicated metallurgical alloying processes takes a lot of baseline, but fabricating pure metallic elements might be tractable. And I was under the impression that pure aluminum and magnesium were actually pretty useful structural elements if you don't have to worry about oxidation?
    - jandrese 7y ago
      They're useful structural elements even in the presence of oxygen. In fact they're better than steel because they form their own protective coating that doesn't flake off and expose fresh metal underneath. The moon has other challenges, like the slow day/night cycle, radiation, and the damn dust.
sveit 7y ago
Starship is a devastatingly powerful space access and logistical transport mechanism that will instantly crush the relevance of every other rocket ever built. If I am a launch provider other than SpaceX, I'm out of business in probably 3-5 years.
- joshmarlow 7y ago
  I would think that pre-existing contracts would keep competitors limping along. Add to that pre-existing relationships + a bit of nepotism, and they might last quite a while.
- QuotedForTruth 7y ago
  The US government won't allow that to happen. Its a national security risk to have only one launch provider available.
  - Robotbeat 7y ago
    And this is true for many other launch providers; most foreign launch providers in particular. But it does make competing for commercial satellites really hard for those firms. ULA basically gave up on commercial launch. We'll have national firms emulating Starship within 5-10 years.
    - greedo 7y ago
      You really think that ULA etc is going to be able to catch up to SpaceX in a decade? For the US, I see SpaceX dominating launch just as Boeing dominated passenger jets. Eventually Congress will realize the fiscal futility of hamstringing NASA. The only thing that Boeing etc will be building will be ICBMs/SLBMs.
      - manicdee 7y ago
        ULA will have engines from Blue Origin, and both ULA and BO will have second mover advantage in designing their own fully reusable launch systems. Once SpaceX has got Starship working even only for LEO missions, China will have a clone up and running within two years. ULA might be a bit slower due to overly zealous bureaucracy. Eventually these launch providers will mean SLS gets cancelled with NASA funding switching more to pure science (eg: building missions to look for life on icy moons, not the rockets to get them there). Congress will continue to hamstring NASA even as their best and brightest depart for commercial operations with bigger R&D budgets.
hsnewman 7y ago
Lets not get ahead of ourselves. The ship hasn't flown once. Also, there is an design issue with the Starship, there is absolutely no redundancy with the fins on the ship. If any of the fins aren't working as planned, prepare for a disaster.
- avmich 7y ago
  > Lets not get ahead of ourselves. The ship hasn't flown once. This is the time when forward thinking won't hurt. We don't see significant problems with reaching this goal - not technical, not economical, not others. There were periods with development of technology - e.g. early airplanes or spacecrafts - which significantly changed the approaches to things, so speculation in worst case would remain just that.
- gpm 7y ago
  By the same logic there is a design error with a boeing 747, if even one wing falls off everyone dies. A wing's controls failing (on either vessel) might be recoverable depending on the details/if the other control surfaces can compensate...
  - hsnewman 7y ago
    It hasn't even flown yet. How can you compare an unproven rocket to a Boeing 747, which has millions of hours of proven flight hours on it with something that has none? I realize that the 747 has had failures over the time too, but I'd happily get on a Boeing 747 but would not get on a Spaceship until it's been flown several, if not 100's of times (without incident, as can be said for the 747).
    - gpm 7y ago
      Lack of fight history is not a design error.. Especially in the context of a spacecraft that is specifically designed to be able to quickly gain a long flight history (unlike every other spacecraft we've ever built).
    - Robotbeat 7y ago
ryan93 7y ago
How much of the worlds fuel would be used doing hundreds or thousands Of launches a year
- zaroth 7y ago
  Approximately none of it.
- ceejayoz 7y ago
  Minimal - a fraction of what we already use on airliners. It's fueled with methane and oxygen. Capture some cow farts and landfill offgassing and you're probably even helping the environment.
  - stetrain 7y ago
    Nice thing is that you can use energy to create methane and oxygen from water and CO2. It's the same process they intend to use on Mars for refuelling. Obviously this is slower and more expensive on Earth than using natural methane, but if volume increases to the point that the fuel burn is an issue you could set this up with a renewable energy source. https://en.wikipedia.org/wiki/Sabatier_reaction https://en.wikipedia.org/wiki/Sabatier_reaction
    - skykooler 7y ago
      Elon said at the IAC two years ago that they plan on doing this on Earth as well - which may seem needlessly complicated, but actually it's a way to test and verify the same components they will need to create fuel on Mars.
- wolfram74 7y ago
  according to this [1] the US consumes ~8E6 million cubic feet of methane a year which is ~ 2.3E11 cubic meters which is ~ 1.5E11 kg of methane 1% of that would be 1.5E9 kg total fuel load of starship+super heavy nominally 4.5E6 kg just the methane is about 30% of that, so 1.4E6 kg so 1% of the total methane consumption of just the US is about a thousand flights a year. As other people have said, minimal. [1] https://www.eia.gov/dnav/ng/hist/n3035us2a.htm https://www.eia.gov/dnav/ng/hist/n3035us2a.htm
QuesnayJr 7y ago
This is far from something I know anything about, but is it really plausible that the Starship is the same complexity as a 737?
- jacobush 7y ago
  My very backseat driver feeling is a Starship is lower complexity?
  - QuesnayJr 7y ago
    Really? The 737 is from the 60s.
    - CydeWeys 7y ago
      Spaceships are surprisingly simple. Starship has much fewer control surfaces, for example. It does have a lot more engines though, and these Raptor engines aren't trivial, so I'm not sure it's actually true.
      - TremendousJudge 7y ago
        As far as I know liquid propellant rocket engines are notoriously complex, and operate under even more extreme conditions than modern airplane engines
        CydeWeys 7y ago
        Don't underestimate how complicated modern high bypass turbofan jet engines are. Way more R&D money had gone into the latest designs than went into e.g. the Raptor engine. A crazy random fact is that there are entire turbine parts that are a single molecule, yet are bigger around than you are tall.
        jacobush 7y ago
        Single molecule thin? Or is it something polymer like? That's intriguing.
jagger27 7y ago
> Starship is not just a huge fuel tank and some kick ass engines, it’s also a reusable honest-to-god Mars landing system for >100T payloads that doesn’t require any parachutes. This is a big deal. No parachutes, landing cushions, skyscranes, or other crazy ideas. Just a big fat cross section to slow it down.
- branchan 7y ago
  Starship still needs to fire rockets in order to land. I would say it's a crazier idea than the ones you have mentioned. The previous solutions you have listed were used precisely because they were less crazy ideas.
  - DuskStar 7y ago
    Curiosity used aerobraking, parachutes AND a skycrane to land. There's a great video here: https://www.youtube.com/watch?v=Ki_Af_o9Q9s https://www.youtube.com/watch?v=Ki_Af_o9Q9s Previous solutions weren't used because they were less crazy, but because they were more mass efficient for "small" payload sizes.
    - branchan 7y ago
      I think we have been desensitized by all these SpaceX rocket landings. Propulsive landing is not as easy as it seems.
crease 7y ago
>Mars city building is about robots building potato farming robots and humans facilitating a nearly-automated industrial stack. Who's going to build these robots? This sounds like something I would really enjoy working on.
- Game_Ender 7y ago
  Sign us both up :).
- 0xffff2 7y ago
  You might have second thoughts when you read about working conditions at SpaceX and Tesla. It's a job I'd love to do and I have enormous respect for Elon Musk, but I have no desire to work for him.
  - DennisP 7y ago
    Yes but so far, Musk has been saying SpaceX plans to let other companies build most of the stuff needed to live on Mars.
sidcool 7y ago
SpaceX is just a phenomenal venture. It's inspiring. I cannot imagine how someone could think of starting a space company.
- avmich 7y ago
  There is a saying "the first trillion of personal wealth will be made in space". Musk seem to be on the way there. Why you "can't imagine" if there is a seeming counterexample - a successful rocket company?
davidhyde 7y ago
I hope SpaceX figures out how to make hydrogen more feasible than methane if they plan to scale up to such high emission levels. I know why hydrogen is not used today. Primarily because of the cryogenic storage requirements in the rocket itself and the requirement to have much larger tanks. Also because of heat problems in the combustion chamber. There are a handful of other reasons but really, the human race should be able to overcome them.
- brunoTbear 7y ago
  Don't forget the impact of hydrogen on metals: turn everything brittle. For a company founded on reusable componentry, Hyrdogen in your turbopumps, fuel chambers, combustion chambers etc. is kind of a deal breaker.
  - avmich 7y ago
    Interesting that RL-10 descendants are quite reusable. Guess they solved the embrittlement problem :) .
  - black6 7y ago
    The SSME (now the RS-25 engine) seems to handle the H2 just fine.
    - DennisP 7y ago
      They only flew each Shuttle an average of 34 times, with months of refurbishing between flights. SpaceX wants to fly each engine hundreds or even thousands of times, with turnaround less than a day.
- m000z0rz 7y ago
  IIRC, SpaceX is planning to generate all their methane using CO2 captured from the atmosphere as a test of the equipment that will do this on Mars.
  - Symmetry 7y ago
haack 7y ago
I'm surprised there's no mention of Kessler Syndrome[1]. Launching, possibly multiple, high volume satellite networks is worrisome to me. Is the increase in number of satellites negated by the reduced launch debris from using reusable rockets? Is there an implication that an increase in global cargo capacity also increases our ability to "launch" debris reduction/removal efforts? [1] https://en.wikipedia.org/wiki/Kessler_syndrome https://en.wikipedia.org/wiki/Kessler_syndrome
- sp332 7y ago
  Satellites in low orbits will experience some amount of drag from a tiny bit of atmosphere, and will naturally de-orbit in a few years unless they are actively boosted. Also, regulators are very aware of the dangers and require all satellites (in any orbit) to have a de-orbit plan and schedule.
- tshannon 7y ago
  Modern satellites (included Starlink) are much better at this than they used to be. However it'd be nice if there was some treaty, agreement, or body that defines and maybe enforces proper retiring of satellites and management of space debris.
  - branchan 7y ago
    Oh yea? https://www.newscientist.com/article/2215303-spacex-satellite-near-miss-shows-need-for-rules-of-the-road-in-space/ https://www.newscientist.com/article/2215303-spacex-satellit...
- klohto 7y ago
  There is not a mention of that because the author knows what he is talking about - https://caseyhandmer.wordpress.com/2019/10/25/space-debris-probably-not-coming-to-a-backyard-near-you/ https://caseyhandmer.wordpress.com/2019/10/25/space-debris-p...
  - haack 7y ago
    Thanks for the link, I hadn't seen this
skybrian 7y ago
There seems to be a lot of wishful thinking in this article? You don't get the Berlin airlift unless someone is willing to pay for it, and that only happened in an emergency. Getting into communication satellites is smart and sounds like it will be big business, but it only goes so far in increasing demand. It should be great in remote and rural areas, but most cities already have Internet.
- DennisP 7y ago
  I've seen estimates that the satellite business will generate more profit for SpaceX than NASA's budget. Since Musk controls over half of the stock, he can do whatever he wants with that.
- ebetica0 7y ago
  According to the ITC, only 11.9% of the world has "Fixed broadband" aka wired internet. 30.1% in developed nations. There's a big gap, especially when the world catches up in a few years.
  - skybrian 7y ago
    Good to know, but it might not be the most relevant metric? In many places, wired phone service got bypassed by cell phone service. I'd guess a lot more people have cell phones and are usually in cell phone range, so what we really want to know is coverage, cost, and quality of the data services that people already use to access the Internet, and how big a role satellite service would play in improving that.
- AtlasBarfed 7y ago
  And yet we waste a trillion dollars a year on the military...
  - reaperducer 7y ago
    Without the military there would be no space program, and no internet for you to moan on.
avmich 7y ago
> It turns out that landing on Mars is really hard. Of 17 attempted landings, only 8 have been successful, all built by JPL. This is practically offtopic, but this is technically incorrect. https://en.wikipedia.org/wiki/Mars_3 https://en.wikipedia.org/wiki/Mars_3 > ...the Mars 3 lander became the first spacecraft to attain a soft landing on Mars, on 2 December 1971. It failed 20 seconds after landing...
- dmix 7y ago
  The number of programs the soviets ran in the 60/70s makes me jealous of that era. One interesting note from the Wikipedia: > This reliability problem was common to much Soviet space hardware from the late 1960s and early 1970s and was largely corrected with a deliberate policy, implemented in the mid-1970s, of consolidating (or "debugging") existing designs rather than introducing new ones. Software developers have learned this well in recent years. Bottom up rewrites being far more risky than improving the legacy system is basically common knowledge at this point.
- branchan 7y ago
  I mean, the whole statement is not correct. Sure JPL manufactured some things but it also acts just like NASA, managing the Mars projects. Most of the spacecraft I would say were manufactured in partnership with other industry aerospace companies.
abakus 7y ago
Since we are at the dawn of the space era, I have always wondered if earth mass loss due to massive space exploration will become a problem.
Animats 7y ago
Space-X has to deal with a PR problem right now. Boeing is going to launch their crewed capsule in December.[1] Space-X isn't ready yet. [1] https://www.nasa.gov/exploration/commercial/crew/index.html https://www.nasa.gov/exploration/commercial/crew/index.html
- pcmonk 7y ago
  Isn't that saying Boeing is going to launch their capsule uncrewed, just like SpaceX did back in March?
- Tuna-Fish 7y ago
  Boeing is doing BOE-OFT, or their uncrewed flight test. SpaceX has already done this. (It was the flight with the earth plushie.) Currently, SpaceX needs to do an in-flight abort, and Boeing needs to do an uncrewed test flight before they can fly crew. Which will be first to the ISS with crew is still up in the air.
trhway 7y ago
>Next, let’s consider Mars. Mars is the underlying design case for the Starship, although Starships that go to Mars will probably be of a customized nature. While the Moon takes about 3 days to get to, Mars takes 4-10 months. Launch windows to Mars only open every 2 years, so even if Elon has 1000 Starships ready to go, they can only go every 2 years. and here i think Musk genius of targeting Mars instead of Moon shows again. Moon business case wouldn't support, while Mars does support the nuclear powered ships. The Starship is of the size to allow sufficient shielding for propulsion reactor. To avoid the "once in 2 years launch window" limitation an additional 3km/s delta-V is needed, and nuclear will get you that and would speed-up the flight in the standard window. Cutting some time from 3 days for Moon isn't really worth the nuclear hassle, cutting half from months long jorneys to Mars and ability to launch practically anytime - that changes everything for Mars. Stacking several Starships - lower ones with reactors, the upper - with people, one can decrease the amount/weight for the shielding. Going ionic thrust propulsion powered by the reactors one can get even faster. All this tech - nuclear propulsion and ionic thrust - had been tried already, so i think it is no less doable for SpaceX than the Raptor with its hot oxygen resistant superallow.
ncmncm 7y ago
Before colonizing Mars, colonize Antarctica. Antarctica is an overwhelmingly better place to live, and to move to, than Mars, on any axis you can name. Actually has air. Has lots of surface water. Has gravity. Is warmer! A flight there or back costs N thousands of times less, and you can get there in a day, not 4-10 months. That's not to say Antarctica is an appealing place to colonize. It's much, much worse than almost any other place on earth. But it's way better than Mars. Even the cloud tops of Venus are way better than Mars. But Antarctica is a way better place to be than Venus, too. Central Australia or the Taklamakan desert would be a picnic compared to Antarctica. Instead of making self-replicating potato-farming robots for Mars, make some for Earth, first. Turn them loose in a desert somewhere: Antarctica, the Sahara, Wrangel Island, or central Australia. I guarantee overwhelmingly better chances for success at any of those places than on Mars. If it would be too hard to do at any of those places, then it will be impossible on Mars. BFStarship has an interesting value proposition for something. Almost anything is a better choice than Mars missions. Delivering milk is a better value proposition. Blockade busting is a better value proposition. Launching communication satellite swarms looks like a good idea, but a viable use for the next dozen vehicles is harder to guess. A space elevator would use up a lot of launches, but that begs the question. Asteroid mining actually seems kind of plausible, in principle, but only if you have something to build out of it, there, like an interstellar generation ship. Nobody has any expectations for those to produce any value.
namirez 7y ago
>Indeed, the marginal cost per flight could fall to $5m or below, reducing launch costs to the neighborhood of $35/kg, or 1000x less than Shuttle. The keyword here is "marginal". You can achieve the $35/kg if you only account for the fuel. In other words, the entire rocket must be retrieved intact and launched again with no maintenance whatsoever. In reality, this will never happen and most likely the cost will be a few hundred dollars per kilogram. For Falcon 9, this number is still above $2000/kg, but even that is way better than other existing launch systems.
- avmich 7y ago
  > In reality, this will never happen and most likely the cost will be a few hundred dollars per kilogram. SpaceX has a history of proving skeptics wrong :) . You didn't elaborate why your opinion is better than those skeptics'.
  - namirez 7y ago
    Well, it's not about my opinion. The cost of launching 1kg to LEO on Falcon 9 is $2700 which is a far cry from $35. Please note that $2700/kg is still great since older launch systems cost about $5k-$10k/kg. We are still talking about a factor of 2-4, not 100.
    - avmich 7y ago
      > Well, it's not about my opinion. It is. You're making statement about the future - what SpaceX will achieve or demonstrate - as if it's a fact. There are plenty of people who disagree with this statement, who have another opinion about the future and who will point out that SpaceX did several times something what was considered at least unlikely. > Please note that $2700/kg is still great When Proton launcher debuted on world market in 1990-s, the price (not cost) for a launch was about 30 millions, which, given payload about 20 tons to LEO, gives price per kg of about 1500 dollars. $2700/kg isn't bad, but isn't record-shattering either. As for costs - as opposed to price - of Falcon-9, we may have only estimation. Two orders of magnitude difference won't likely be achieved immediately, but the potential is here. See the evolution of airlines.

432 points by mrfusion 7y ago

Starship is a cargo conveyor system. The Starship is comparable in complexity to a 737, and so it’s not unthinkable to have a construction rate of 500/year. If each Starship manages 300 flights per year, each carrying 150 T of cargo, then we are talking a yearly incremental cargo capacity growth of 22 million tonnes to orbit. At this point, the most meaningful constraint on launch capacity might be launch pad construction rate. This made me think of this shot in Star Trek: Into Darkness https://scifi.stackexchange.com/questions/127311/why-is-a-model-of-the-secret-starship-in-plain-view https://scifi.stackexchange.com/questions/127311/why-is-a-mo...

gameswithgo 7y ago
why?
- carrozo 7y ago
  It's that tracking shot where it starts with spaceships we're familiar with in our own "timeline" like the Space Shuttle and works up to larger and larger vessels, including Enterprise. Suppose having the ability to ferry more and more cargo to low earth orbit means we can start creating much larger structures in space?

bryanlarsen 7y ago

> With an eventual flight rate of once per day per Starship, Gwynne Shotwell said that their business plan for using Starship to compete with long-distance airliners involved making about a dozen trips per day per Starship.

avmich 7y ago
> about a dozen trips per day per Starship Gagarin flew for around 108 minutes, so orbital velocity allows longest trip between two points on Earth in about 54 minutes. Shorter trips could be less, but liftoff-landing take roughly a fixed amount of time. Twelve trips per day is 2 hours per trip. Taking 40 minutes of flight, there are 1 hour 20 minutes to get onboard, to get off board, to handle luggage (if needed?), to refuel and check systems. Wonder how does it look from airlines operation prospective.
- madaxe_again 7y ago
  That stands pretty much parallel with aviation turnarounds - it’s purely logistics. If they don’t need to do any maintenance other than standardised checklists between flights, which is their ambition, there’s no fundamental reason they couldn’t do this.
- deadbunny 7y ago
  A (very) cursory search turned up this[1], which suggests they can turn around what appears to be a relatively short haul aircraft in ~50 mins arrival to departure. My uneducated guess would be that refueling of a starship alone is likely to take a long time if you're pumping in 1,200 tons of fuel. 1. https://your.heathrow.com/happens-aircraft-turn-around-british-airways/ https://your.heathrow.com/happens-aircraft-turn-around-briti...
- Consultant32452 7y ago
  Do all orbital flights take off in the same direction due to the rotation of the Earth?
  - gpm 7y ago
    "Most" would be more accurate. Flights that want to orbit over the poles take off aiming perpendicular to the rotation instead. A few satellites have been launched backwards intentionally.
    - isostatic 7y ago
      I think sun synchronous orbits are retrograde P2P sub orbital hops are either direction, 30-40 minutes, maybe 25 for shorter trips like London to New York.
      - gpm 7y ago
        Agreed that P2P sub orbital hops are any direction. Low sun synchronous orbits are approximately the same as polar oribts, more perpendicular than retrograde. I'm not sure if we use high sun synchronous orbits for anything?
gameswithgo 7y ago
I wonder if anyone with sufficient experience in rockets could comment on whether that idea is at all plausible.
- chasd00 7y ago
  i have no experience but, man, it would be so freaking noisy. where would they take off and land?
  - donkeyd 7y ago
    Yup, that's the big issue. Being able to fly London to NY in 30 minutes is great, but the landing/launch sites will have to be pretty far from the cities to have the sonic booms not break windows all the time. That increases total travel time.
    - ralusek 7y ago
      And then you can just travel through Boring tunnels.
    - deadbunny 7y ago
      Some routes would definitely be worth it. Opposite sides of the world would become connected like never before. If I could catch a "flight" to Australia (from the UK) in the time it takes to fly to New York it would be game changing. Hell even 4 hours to LA would be preferable to the 11 hour flight time + 2 hours either side it takes now.
      - jandrese 7y ago
        But would you be willing to pay 10x or 20x the cost of a "slow" conventional airline ticket for it? The fuel costs may be low by space launch standards, but they'll be huge by commercial airline standards.
        bryanlarsen 7y ago
DennisP 7y ago
And in his recent big presentation, Musk said they hoped to ultimately reach three daily flights to orbit for each Starship, and thirty per day for each first stage. He said at that rate, with ten Starships they would have a thousand times the launch capacity of the entire world right now including Falcon 9/Heavy.
tbabb 7y ago
This is not happening soon. Safety/redundancy of rockets (including SpaceX's) compared to airliners is abysmal—about five orders of magnitude worse. With passenger manifests in the hundreds (necessary for the economics to work), and with any failure being catastrophic, you'll be seeing multiple Tenerife disasters [1] per year. You also can't launch a rocket (especially one that big) anywhere near a major city for sound and safety reasons, which means at best you are building an offshore spaceport, which is terrible for the logistics and economics. But that's still nothing compared to the safety problem. [1] https://en.m.wikipedia.org/wiki/Tenerife_airport_disaster https://en.m.wikipedia.org/wiki/Tenerife_airport_disaster
- randyrand 7y ago
  When does startship need to light its engines on landing? What about landing in a 2000 foot deep hole in the ground?
  - tbabb 7y ago
    I don't follow. What's the hole for?
    - jandrese 7y ago
      Presumably to let it hold off on lighting the engines until it is below the surface of the Earth, to avoid radiating the sound outward.
      - tbabb 7y ago
        Setting aside the economic infeasibility of a 2000 foot hole, the rocket's gonna have to fly out of it at some point.
- londons_explore 7y ago
  The sound reasons could potentially be mitigated by launching behind a wall, acting as a sound reflector right? Humans can build walls 1km high or more without much difficulty, and by the time the rocket is 1km up, it is already moving pretty fast, and is already much further away.

chasd00 7y ago

to me, it's the Raptor engine that is the big deal. And within the Raptor, it's the alloy developed on the oxidizer side pre-burner that's the big deal. I wish i could have been there the moment that alloy was conceived and the moment it past the first round of testing. I would have poured so much tequila it would have had a budget impact.

serioussecurity 7y ago
Tell me more.
- chasd00 7y ago
  "So, SpaceX developed their own superalloy in house that they named SX500. According to Elon, it’s capable of over 800 bar of hot oxygen-rich gas. That may have been one of the biggest hurdles in developing the Raptor engine." almost halfway down, the article is long but so well worth the time. https://everydayastronaut.com/raptor-engine/ https://everydayastronaut.com/raptor-engine/
  - wolfram74 7y ago
    The reason "over 800 bar of hot oxygen-rich gas" is a high hurdle to break is the propensity for a metal to rust and become useless is proportional to the pressure (concentration) of the oxidizer (oxygen) it's surrounded in and how hot it is. So this metal is able to withstand 800 bar (1 bar ~=1 atmosphere), or 4 thousand times as much oxygen as sea level, at quite elevated temperatures. This is a hellish environment to not just immediately combust in.
    - Tuna-Fish 7y ago
      And note that at 800 bars of hot oxygen, metal doesn't so much rust as it burns with a bright flame. The environment in the Raptor oxy-rich preburner is much worse than the typical oxyacetylene torch that is used to cut steel.
Robotbeat 7y ago

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PaulHoule 7y ago

The lunar mission profiled in there takes 15 tanker launches, which is a lot. As for in-situ resource utilization, how about this: Apollo astronauts found nearly 40% iron ore in some areas of lunar regolith. That may be unusually high, but you can do magnetic separation, then pass hydrogen gas through the ore to get iron and water. Crack the water molecules, recycle the hydrogen, and then use the oxygen to refuel "starships", where it accounts for 4/5 of the propellant mass. In the meantime you get iron by the hundreds of tons on La Luna that you can use to make pressure tanks to store that oxygen, live in, etc. (It's been a long trope in sci-fi and speculation that a lunar economy would be an aluminium economy, and that people who seek iron will go for the asteroids, but it is very easy to get iron + oxygen as described on the moon, it is much harder to reduce other common metals on the moon.) Here is the mass driver that Gerard K. O'Neill told you about, available off the shelf: https://www.youtube.com/watch?v=58MmOpSm4LY https://www.youtube.com/watch?v=58MmOpSm4LY That can send a 10kg projectile at 2.5 km/s which can get to the Earth-Moon L1 or L2 points. If you can increase the velocity to 3.1 km/s you could graze the Earth's atmosphere and deliver oxygen and other materials to LEO. Either way you need something that can soak up excess momentum at the end, but you could greatly reduce the need for tanker launches.

bryanlarsen 7y ago
> The lunar mission profiled in there takes 15 tanker launches, which is a lot. Using pre-Starship capabilities, 15 launches is a lot. At $5M/launch, 3 launches per day that they're forecasting for Startship, 15 launches would be a tiny part of the budget.
whatshisface 7y ago
Pure iron is a poor material. You would want some carbon to turn it in to steel, and that would have to come from another process.
- PaulHoule 7y ago
  If your space economy is driven my methane (e.g. the Starship fuel) you could ship methane to the moon, separate the carbon from the hydrogen, recycle the hydrogen and mix the carbon in with the iron. Mild steel might have 0.1% carbon so you get a multiplication ratio in the 100's. The main trouble is you also want to build up a carbon stock for biological applications... But it is the nitrogen stock that I haven't figured out.

avmich 7y ago

> If each Starship manages 300 flights per year, each carrying 150 T of cargo, then we are talking a yearly incremental cargo capacity growth of 22 million tonnes to orbit. https://en.wikipedia.org/wiki/Space_sunshade https://en.wikipedia.org/wiki/Space_sunshade > One proposed sunshade would be composed of 16 trillion small disks at the Sun-Earth L1 Lagrangian point, 1.5 million kilometers above Earth. Each disk is proposed to have a 0.6-meter diameter and a thickness of about 5 micrometers. The mass of each disk would be about a gram, adding up to a total of almost 20 million tonnes.[3] Such a group of small sunshades that blocks 2% of the sunlight, deflecting it off into space, would be enough to halt global warming, giving us ample time to cut our emissions back on earth.

deleted 7y ago
[deleted]
7777fps 7y ago
And if that works, and we restore a more normal cycle, how do we avert the next ice-age with all that space junk?
- xur17 7y ago
  We remove it?
- _ph_ 7y ago
  If it isn't automatic the case, the material for the discs could be designed such that it dissolves in the normal solar radiation after a decade or so.
  - beerandt 7y ago
    Can't dissolve without a solvent.
    - avmich 7y ago
      Do you know what happened to USA flags which astronauts installed on the Moon?

Tepix 7y ago

I wonder if we will revive O'Neill's idea of putting a mass driver on the Moon. That would potentially enable getting mass (like water or lunar regolith) into space (alas from the Moon, not Earth) at even lower cost than Starship. Recommended related link: http://ssi.org/ssi-supermodels-part-2-make-your-own-ssi-mass-driver/ http://ssi.org/ssi-supermodels-part-2-make-your-own-ssi-mass...

wolfram74 7y ago
This paper [1] estimated a mildly useful launcher could be delivered to the moon with no in-situ production for 9 falcon heavy launches, or half of a nominal starship payload. [1] https://www.researchgate.net/publication/276039810_Mass_Estimate_for_a_Lunar_Resource_Launcher_Based_on_Existing_Terrestrial_Electromagnetic_Launchers https://www.researchgate.net/publication/276039810_Mass_Esti...
skykooler 7y ago
The big limitation for constructing something like that is setting up a manufacturing industry on the Moon: even with Starship, a mass driver requires far more processed material (mainly refined metals) than can be practically shipped up from Earth. The tipping point for a Lunar mass driver will be when we've created enough of an industry on the Moon to construct it out of local materials.
- wolfram74 7y ago
  Obviously complicated metallurgical alloying processes takes a lot of baseline, but fabricating pure metallic elements might be tractable. And I was under the impression that pure aluminum and magnesium were actually pretty useful structural elements if you don't have to worry about oxidation?
  - jandrese 7y ago
    They're useful structural elements even in the presence of oxygen. In fact they're better than steel because they form their own protective coating that doesn't flake off and expose fresh metal underneath. The moon has other challenges, like the slow day/night cycle, radiation, and the damn dust.

sveit 7y ago

Starship is a devastatingly powerful space access and logistical transport mechanism that will instantly crush the relevance of every other rocket ever built. If I am a launch provider other than SpaceX, I'm out of business in probably 3-5 years.

joshmarlow 7y ago
I would think that pre-existing contracts would keep competitors limping along. Add to that pre-existing relationships + a bit of nepotism, and they might last quite a while.
QuotedForTruth 7y ago
The US government won't allow that to happen. Its a national security risk to have only one launch provider available.
- Robotbeat 7y ago
  And this is true for many other launch providers; most foreign launch providers in particular. But it does make competing for commercial satellites really hard for those firms. ULA basically gave up on commercial launch. We'll have national firms emulating Starship within 5-10 years.
  - greedo 7y ago
    You really think that ULA etc is going to be able to catch up to SpaceX in a decade? For the US, I see SpaceX dominating launch just as Boeing dominated passenger jets. Eventually Congress will realize the fiscal futility of hamstringing NASA. The only thing that Boeing etc will be building will be ICBMs/SLBMs.
    - manicdee 7y ago
      ULA will have engines from Blue Origin, and both ULA and BO will have second mover advantage in designing their own fully reusable launch systems. Once SpaceX has got Starship working even only for LEO missions, China will have a clone up and running within two years. ULA might be a bit slower due to overly zealous bureaucracy. Eventually these launch providers will mean SLS gets cancelled with NASA funding switching more to pure science (eg: building missions to look for life on icy moons, not the rockets to get them there). Congress will continue to hamstring NASA even as their best and brightest depart for commercial operations with bigger R&D budgets.

hsnewman 7y ago

Lets not get ahead of ourselves. The ship hasn't flown once. Also, there is an design issue with the Starship, there is absolutely no redundancy with the fins on the ship. If any of the fins aren't working as planned, prepare for a disaster.

avmich 7y ago
> Lets not get ahead of ourselves. The ship hasn't flown once. This is the time when forward thinking won't hurt. We don't see significant problems with reaching this goal - not technical, not economical, not others. There were periods with development of technology - e.g. early airplanes or spacecrafts - which significantly changed the approaches to things, so speculation in worst case would remain just that.
gpm 7y ago
By the same logic there is a design error with a boeing 747, if even one wing falls off everyone dies. A wing's controls failing (on either vessel) might be recoverable depending on the details/if the other control surfaces can compensate...
- hsnewman 7y ago
  It hasn't even flown yet. How can you compare an unproven rocket to a Boeing 747, which has millions of hours of proven flight hours on it with something that has none? I realize that the 747 has had failures over the time too, but I'd happily get on a Boeing 747 but would not get on a Spaceship until it's been flown several, if not 100's of times (without incident, as can be said for the 747).
  - gpm 7y ago
    Lack of fight history is not a design error.. Especially in the context of a spacecraft that is specifically designed to be able to quickly gain a long flight history (unlike every other spacecraft we've ever built).
  - Robotbeat 7y ago

ryan93 7y ago

How much of the worlds fuel would be used doing hundreds or thousands Of launches a year

zaroth 7y ago
Approximately none of it.
ceejayoz 7y ago
Minimal - a fraction of what we already use on airliners. It's fueled with methane and oxygen. Capture some cow farts and landfill offgassing and you're probably even helping the environment.
- stetrain 7y ago
  Nice thing is that you can use energy to create methane and oxygen from water and CO2. It's the same process they intend to use on Mars for refuelling. Obviously this is slower and more expensive on Earth than using natural methane, but if volume increases to the point that the fuel burn is an issue you could set this up with a renewable energy source. https://en.wikipedia.org/wiki/Sabatier_reaction https://en.wikipedia.org/wiki/Sabatier_reaction
  - skykooler 7y ago
    Elon said at the IAC two years ago that they plan on doing this on Earth as well - which may seem needlessly complicated, but actually it's a way to test and verify the same components they will need to create fuel on Mars.
wolfram74 7y ago
according to this [1] the US consumes ~8E6 million cubic feet of methane a year which is ~ 2.3E11 cubic meters which is ~ 1.5E11 kg of methane 1% of that would be 1.5E9 kg total fuel load of starship+super heavy nominally 4.5E6 kg just the methane is about 30% of that, so 1.4E6 kg so 1% of the total methane consumption of just the US is about a thousand flights a year. As other people have said, minimal. [1] https://www.eia.gov/dnav/ng/hist/n3035us2a.htm https://www.eia.gov/dnav/ng/hist/n3035us2a.htm

QuesnayJr 7y ago

This is far from something I know anything about, but is it really plausible that the Starship is the same complexity as a 737?

jacobush 7y ago
My very backseat driver feeling is a Starship is lower complexity?
- QuesnayJr 7y ago
  Really? The 737 is from the 60s.
  - CydeWeys 7y ago
    Spaceships are surprisingly simple. Starship has much fewer control surfaces, for example. It does have a lot more engines though, and these Raptor engines aren't trivial, so I'm not sure it's actually true.
    - TremendousJudge 7y ago
      As far as I know liquid propellant rocket engines are notoriously complex, and operate under even more extreme conditions than modern airplane engines
      - CydeWeys 7y ago
        Don't underestimate how complicated modern high bypass turbofan jet engines are. Way more R&D money had gone into the latest designs than went into e.g. the Raptor engine. A crazy random fact is that there are entire turbine parts that are a single molecule, yet are bigger around than you are tall.
        jacobush 7y ago
        Single molecule thin? Or is it something polymer like? That's intriguing.

jagger27 7y ago

> Starship is not just a huge fuel tank and some kick ass engines, it’s also a reusable honest-to-god Mars landing system for >100T payloads that doesn’t require any parachutes. This is a big deal. No parachutes, landing cushions, skyscranes, or other crazy ideas. Just a big fat cross section to slow it down.

branchan 7y ago
Starship still needs to fire rockets in order to land. I would say it's a crazier idea than the ones you have mentioned. The previous solutions you have listed were used precisely because they were less crazy ideas.
- DuskStar 7y ago
  Curiosity used aerobraking, parachutes AND a skycrane to land. There's a great video here: https://www.youtube.com/watch?v=Ki_Af_o9Q9s https://www.youtube.com/watch?v=Ki_Af_o9Q9s Previous solutions weren't used because they were less crazy, but because they were more mass efficient for "small" payload sizes.
  - branchan 7y ago
    I think we have been desensitized by all these SpaceX rocket landings. Propulsive landing is not as easy as it seems.

crease 7y ago

>Mars city building is about robots building potato farming robots and humans facilitating a nearly-automated industrial stack. Who's going to build these robots? This sounds like something I would really enjoy working on.

Game_Ender 7y ago
Sign us both up :).
0xffff2 7y ago
You might have second thoughts when you read about working conditions at SpaceX and Tesla. It's a job I'd love to do and I have enormous respect for Elon Musk, but I have no desire to work for him.
- DennisP 7y ago
  Yes but so far, Musk has been saying SpaceX plans to let other companies build most of the stuff needed to live on Mars.

sidcool 7y ago

SpaceX is just a phenomenal venture. It's inspiring. I cannot imagine how someone could think of starting a space company.

avmich 7y ago
There is a saying "the first trillion of personal wealth will be made in space". Musk seem to be on the way there. Why you "can't imagine" if there is a seeming counterexample - a successful rocket company?

davidhyde 7y ago

I hope SpaceX figures out how to make hydrogen more feasible than methane if they plan to scale up to such high emission levels. I know why hydrogen is not used today. Primarily because of the cryogenic storage requirements in the rocket itself and the requirement to have much larger tanks. Also because of heat problems in the combustion chamber. There are a handful of other reasons but really, the human race should be able to overcome them.

brunoTbear 7y ago
Don't forget the impact of hydrogen on metals: turn everything brittle. For a company founded on reusable componentry, Hyrdogen in your turbopumps, fuel chambers, combustion chambers etc. is kind of a deal breaker.
- avmich 7y ago
  Interesting that RL-10 descendants are quite reusable. Guess they solved the embrittlement problem :) .
- black6 7y ago
  The SSME (now the RS-25 engine) seems to handle the H2 just fine.
  - DennisP 7y ago
    They only flew each Shuttle an average of 34 times, with months of refurbishing between flights. SpaceX wants to fly each engine hundreds or even thousands of times, with turnaround less than a day.
m000z0rz 7y ago
IIRC, SpaceX is planning to generate all their methane using CO2 captured from the atmosphere as a test of the equipment that will do this on Mars.
- Symmetry 7y ago

haack 7y ago

I'm surprised there's no mention of Kessler Syndrome[1]. Launching, possibly multiple, high volume satellite networks is worrisome to me. Is the increase in number of satellites negated by the reduced launch debris from using reusable rockets? Is there an implication that an increase in global cargo capacity also increases our ability to "launch" debris reduction/removal efforts? [1] https://en.wikipedia.org/wiki/Kessler_syndrome https://en.wikipedia.org/wiki/Kessler_syndrome

sp332 7y ago
Satellites in low orbits will experience some amount of drag from a tiny bit of atmosphere, and will naturally de-orbit in a few years unless they are actively boosted. Also, regulators are very aware of the dangers and require all satellites (in any orbit) to have a de-orbit plan and schedule.
tshannon 7y ago
Modern satellites (included Starlink) are much better at this than they used to be. However it'd be nice if there was some treaty, agreement, or body that defines and maybe enforces proper retiring of satellites and management of space debris.
- branchan 7y ago
  Oh yea? https://www.newscientist.com/article/2215303-spacex-satellite-near-miss-shows-need-for-rules-of-the-road-in-space/ https://www.newscientist.com/article/2215303-spacex-satellit...
klohto 7y ago
There is not a mention of that because the author knows what he is talking about - https://caseyhandmer.wordpress.com/2019/10/25/space-debris-probably-not-coming-to-a-backyard-near-you/ https://caseyhandmer.wordpress.com/2019/10/25/space-debris-p...
- haack 7y ago
  Thanks for the link, I hadn't seen this

skybrian 7y ago

There seems to be a lot of wishful thinking in this article? You don't get the Berlin airlift unless someone is willing to pay for it, and that only happened in an emergency. Getting into communication satellites is smart and sounds like it will be big business, but it only goes so far in increasing demand. It should be great in remote and rural areas, but most cities already have Internet.

DennisP 7y ago
I've seen estimates that the satellite business will generate more profit for SpaceX than NASA's budget. Since Musk controls over half of the stock, he can do whatever he wants with that.
ebetica0 7y ago
According to the ITC, only 11.9% of the world has "Fixed broadband" aka wired internet. 30.1% in developed nations. There's a big gap, especially when the world catches up in a few years.
- skybrian 7y ago
  Good to know, but it might not be the most relevant metric? In many places, wired phone service got bypassed by cell phone service. I'd guess a lot more people have cell phones and are usually in cell phone range, so what we really want to know is coverage, cost, and quality of the data services that people already use to access the Internet, and how big a role satellite service would play in improving that.
AtlasBarfed 7y ago
And yet we waste a trillion dollars a year on the military...
- reaperducer 7y ago
  Without the military there would be no space program, and no internet for you to moan on.

avmich 7y ago

> It turns out that landing on Mars is really hard. Of 17 attempted landings, only 8 have been successful, all built by JPL. This is practically offtopic, but this is technically incorrect. https://en.wikipedia.org/wiki/Mars_3 https://en.wikipedia.org/wiki/Mars_3 > ...the Mars 3 lander became the first spacecraft to attain a soft landing on Mars, on 2 December 1971. It failed 20 seconds after landing...

dmix 7y ago
The number of programs the soviets ran in the 60/70s makes me jealous of that era. One interesting note from the Wikipedia: > This reliability problem was common to much Soviet space hardware from the late 1960s and early 1970s and was largely corrected with a deliberate policy, implemented in the mid-1970s, of consolidating (or "debugging") existing designs rather than introducing new ones. Software developers have learned this well in recent years. Bottom up rewrites being far more risky than improving the legacy system is basically common knowledge at this point.
branchan 7y ago
I mean, the whole statement is not correct. Sure JPL manufactured some things but it also acts just like NASA, managing the Mars projects. Most of the spacecraft I would say were manufactured in partnership with other industry aerospace companies.

abakus 7y ago

Since we are at the dawn of the space era, I have always wondered if earth mass loss due to massive space exploration will become a problem.

Animats 7y ago

Space-X has to deal with a PR problem right now. Boeing is going to launch their crewed capsule in December.[1] Space-X isn't ready yet. [1] https://www.nasa.gov/exploration/commercial/crew/index.html https://www.nasa.gov/exploration/commercial/crew/index.html

pcmonk 7y ago
Isn't that saying Boeing is going to launch their capsule uncrewed, just like SpaceX did back in March?
Tuna-Fish 7y ago
Boeing is doing BOE-OFT, or their uncrewed flight test. SpaceX has already done this. (It was the flight with the earth plushie.) Currently, SpaceX needs to do an in-flight abort, and Boeing needs to do an uncrewed test flight before they can fly crew. Which will be first to the ISS with crew is still up in the air.

trhway 7y ago

>Next, let’s consider Mars. Mars is the underlying design case for the Starship, although Starships that go to Mars will probably be of a customized nature. While the Moon takes about 3 days to get to, Mars takes 4-10 months. Launch windows to Mars only open every 2 years, so even if Elon has 1000 Starships ready to go, they can only go every 2 years. and here i think Musk genius of targeting Mars instead of Moon shows again. Moon business case wouldn't support, while Mars does support the nuclear powered ships. The Starship is of the size to allow sufficient shielding for propulsion reactor. To avoid the "once in 2 years launch window" limitation an additional 3km/s delta-V is needed, and nuclear will get you that and would speed-up the flight in the standard window. Cutting some time from 3 days for Moon isn't really worth the nuclear hassle, cutting half from months long jorneys to Mars and ability to launch practically anytime - that changes everything for Mars. Stacking several Starships - lower ones with reactors, the upper - with people, one can decrease the amount/weight for the shielding. Going ionic thrust propulsion powered by the reactors one can get even faster. All this tech - nuclear propulsion and ionic thrust - had been tried already, so i think it is no less doable for SpaceX than the Raptor with its hot oxygen resistant superallow.

ncmncm 7y ago

Before colonizing Mars, colonize Antarctica. Antarctica is an overwhelmingly better place to live, and to move to, than Mars, on any axis you can name. Actually has air. Has lots of surface water. Has gravity. Is warmer! A flight there or back costs N thousands of times less, and you can get there in a day, not 4-10 months. That's not to say Antarctica is an appealing place to colonize. It's much, much worse than almost any other place on earth. But it's way better than Mars. Even the cloud tops of Venus are way better than Mars. But Antarctica is a way better place to be than Venus, too. Central Australia or the Taklamakan desert would be a picnic compared to Antarctica. Instead of making self-replicating potato-farming robots for Mars, make some for Earth, first. Turn them loose in a desert somewhere: Antarctica, the Sahara, Wrangel Island, or central Australia. I guarantee overwhelmingly better chances for success at any of those places than on Mars. If it would be too hard to do at any of those places, then it will be impossible on Mars. BFStarship has an interesting value proposition for something. Almost anything is a better choice than Mars missions. Delivering milk is a better value proposition. Blockade busting is a better value proposition. Launching communication satellite swarms looks like a good idea, but a viable use for the next dozen vehicles is harder to guess. A space elevator would use up a lot of launches, but that begs the question. Asteroid mining actually seems kind of plausible, in principle, but only if you have something to build out of it, there, like an interstellar generation ship. Nobody has any expectations for those to produce any value.

namirez 7y ago

>Indeed, the marginal cost per flight could fall to $5m or below, reducing launch costs to the neighborhood of $35/kg, or 1000x less than Shuttle. The keyword here is "marginal". You can achieve the $35/kg if you only account for the fuel. In other words, the entire rocket must be retrieved intact and launched again with no maintenance whatsoever. In reality, this will never happen and most likely the cost will be a few hundred dollars per kilogram. For Falcon 9, this number is still above $2000/kg, but even that is way better than other existing launch systems.

avmich 7y ago
> In reality, this will never happen and most likely the cost will be a few hundred dollars per kilogram. SpaceX has a history of proving skeptics wrong :) . You didn't elaborate why your opinion is better than those skeptics'.
- namirez 7y ago
  Well, it's not about my opinion. The cost of launching 1kg to LEO on Falcon 9 is $2700 which is a far cry from $35. Please note that $2700/kg is still great since older launch systems cost about $5k-$10k/kg. We are still talking about a factor of 2-4, not 100.
  - avmich 7y ago
    > Well, it's not about my opinion. It is. You're making statement about the future - what SpaceX will achieve or demonstrate - as if it's a fact. There are plenty of people who disagree with this statement, who have another opinion about the future and who will point out that SpaceX did several times something what was considered at least unlikely. > Please note that $2700/kg is still great When Proton launcher debuted on world market in 1990-s, the price (not cost) for a launch was about 30 millions, which, given payload about 20 tons to LEO, gives price per kg of about 1500 dollars. $2700/kg isn't bad, but isn't record-shattering either. As for costs - as opposed to price - of Falcon-9, we may have only estimation. Two orders of magnitude difference won't likely be achieved immediately, but the potential is here. See the evolution of airlines.