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Commercialization

SpaceX Now Quotes Payload Launch Prices – To Mars

By Keith Cowing
NASA Watch
May 1, 2016
Filed under ,
SpaceX Now Quotes Payload Launch Prices – To Mars

Crazy diamonds: Billionaires are funding lots of grandiose plans. Welcome their ambition, Economist
“Mr. Musk lists his ultimate goal as “enabling people to live on other planets”. Once upon a time the space race was driven by the competition between capitalism and communism. Now it is driven by the competition between individual capitalists.”
With or Without NASA, SpaceX Is Going to Mars, Motley Fool
“What it means for investors: Unless and until SpaceX goes public, most of the above probably seems academic. We can’t invest in SpaceX today; perhaps we never will. Be that as it may, one thing is clear: Mankind is going to Mars, and sooner than you think. That this will open up the possibilities of new investments — literally out-of-this-world investments — seems almost certain.”
Changing The Way We Explore Space, earlier post
“SpaceX has their own vertically integrated launch and spacecraft company that can produce absolutely everything needed to do this mission. And they have enough money to do missions on their own. More importantly they have a leader who is compelled to explore Mars and he owns the company. They do not need NASA to do this mission.”

NASA Watch founder, Explorers Club Fellow, ex-NASA, Away Teams, Journalist, Space & Astrobiology, Lapsed climber.

55 responses to “SpaceX Now Quotes Payload Launch Prices – To Mars”

  1. Paul F. Dietz says:
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    The F9 payload to LEO seems to have gone up a lot.

    • fcrary says:
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      I think payload to low Earth orbit more than doubled going from the Falcon 9 v1.0 to v1.1 full thrust.

      • Paul F. Dietz says:
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        The figure given is now just slightly below the max payload the shuttle could take to LEO.

      • duheagle says:
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        And the Falcon Heavy LEO payload is now 54.4 tonnes max without crossfeed. That’s $750/lb. to LEO on an expendable launch unless there’s a higher price for such missions. Be nice to see what the payload figures and prices are for all recoverability options.

    • Jeff2Space says:
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      Yes they have. Musk tweeted that due to extensive testing, they’re going to increase the thrust of the Merlin engines, resulting in a payload increase for both Falcon 9 and Falcon Heavy.

  2. fcrary says:
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    Forget Mars, the Falcon Heavy page now has a payload to Pluto listed (2900 kg.) I assume that’s for a Hohmann transfer which would take about 90 years. Actually, I assume someone has a sense of humor.

    • Terry Stetler says:
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      It won’t be so funny if they actually build the USAF Raptor methane upper stage.

    • Michael Spencer says:
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      Someone has a sense of history.

      Outfitters in St. Louis used to price ‘packages’ to westbound settlers similarly.

  3. Wayne Martin says:
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    I wonder what the whole platform would cost?

    Hell… just Drive the Rover out the Bloody front door lmao ;)… for that matter drive all 5 of them out! 14 tons? WOW! And I know that’s not all payload, still it does opens up so many possibilities!

    Think about what could be possible? You don’t have to take some piece of science equipment and spend what… $100 million shrinking it down to something the size of a shoebox…

    I’m going to find it awful hard to look at another flagship mission without knowing this would of, could of, been an option for anyone… and for what? $250 million? (guessing)…

    I also wonder how many Senator Shelby’s will come out of the woodwork swinging when it affects their district…

    This could have a snowballing effect as well… especially when SLS eventually dies?

    How many billions? Like 15 billion?

    • Paul451 says:
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      Drive the Rover out the Bloody front door […]
      You don’t have to take some piece of science equipment and [shrink] it down to something the size of a shoebox…

      Actually you still would, it’s a small door. And nearly 2 metres off the ground.

      So you’ll still need a rover that can be folded up for deployment, although it can be 2.5m long. And you’ll need a reliable way of getting it to the ground, without anything that can jam.

      • Ben Russell-Gough says:
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        The MERs had semi-flexible ‘rolled carpet’ egress ramps off of their EDL platforms. Could such a thing work with driving something out of the Dragon-2’s egress hatch?

        • Paul451 says:
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          The MER-lander was very low. The MER-rovers just needed something to keep their wheels from tangling in the deflated airbags.

          Dragon’s hatch is nearly 2m above the ground. According to people who make them for a living, rovers are limited to around a 15° ramp, so around 7 metres long and strong enough to support itself and the perhaps 1 tonne rover. Not likely to be something that could just unfold from the hatch.

          (I suggested a different variant in the other thread.)

      • Wayne Martin says:
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        I was somewhat kidding although you would have a huge mothership on Mars (Dragon 2) that could preform the science… You wouldn’t need a Huge Rover which usually has to carry all the science instruments on-board… What kind of science could you do with the available volume Dragon 2 has to offer?

      • fcrary says:
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        Some experiments only need a clear view upward, or to be out in the air. Does the hatch on top open inward or outward? It effects how much clearance you’d need. (After the hatch is open, how much would you have to raise the instrument platform?)

        • Paul451 says:
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          The hatch normally opens inwards. This is obviously the ideal way to seal against a pressure difference, the internal pressure helps clamp it shut, which is what you want for Dragon-Cargo and Dragon-Crew. The hatches also have to open and reseal, so are much more robust than you need for a single one-time event. And they have to attach to ISS, so they have a bunch of stuff dedicated solely to creating a seal against another docking/berthing hatch.

          But for a Mars mission, SpaceX could modify the hatch to anything they want. Outward opening, full-width, one-time action.

          (Dragon Crew (D2) capsule has a completely different hatch (an active docking hatch) than the Dragon Cargo (D1) capsule (a passive berthing hatch). The latter is much wider. But the pressure vessel itself is the same. Not just the hatches, but the hatch-surrounds/frames/etc are separately manufactured units that are then built in. In the same way that the thruster units are attached in the space allowed for them.)

          The wider square hatch (cargo, berthing) is about 1.3m wide. The crew hatch is much smaller, so I’ll ignore that. But if you replaced the entire hatch assembly with a since pivoting or jettisoning cover, the entire available opening is a circle 1.8m across.

          The internal height in the Dragon pressure vessel is about 2m from floor to below the hatch. So if you were raising an instrument rack, that’s your potential column height. But the launch cover domes over the top of the capsule, and so you could have a hatch that isn’t flat, but gives you an extra half-metre or so, or even skip the hatch entirely. The sample-return proposal has the top of the sample-return-rocket actually sticking out of the hatch-area.

          2.5m high, 1.8m diameter is a fairly big volume for instruments. And you still have another 5m³ in the capsule for fixed instruments, rad-protected computers, batteries, etc.

          • fcrary says:
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            Thanks for the information on the existing systems. But I don’t think modifications to the vehicle are in the cards. I’m not even sure any money for any sort of science payload is in the cards.

            I’m thinking in terms of what could be done, if SpaceX or NASA said, “Here’s $500,000. Do the best you can with that, that’s little enough we wouldn’t care if it fails, but no matter what, don’t do anything to interfere with our EDL test.” I think that’s more likely than multi-million dollar instrument packages requiring modifications to the Dragon.

          • Paul451 says:
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            The modifications I’m talking about are “Leaving the hatch-assembly off”.

            Worst case, “Making a jettisonable cover”, probably vastly cheaper than the cost of modifying an existing conventional hatch to allow automated opening.

            As for funding for the science itself. If SpaceX was, in essence, offering a free trip to Mars, I imagine there’d be plenty of groups who could get enough self-funding (agencies, universities, etc) to pay for instrument packages. Particularly if you are half expecting the first Red Dragon landing attempt to fail, so you deliberately treat your design as similarly expendable (low-cost, non-rad-hardened off-the-shelf electronics, for eg.)

            You’ll note that no-one actually launches a dummy payload for the first orbital flight of a brand new launcher. There’s always someone that will accept the free launch, no matter the risk.

            Aside:

            the Falcon Heavy page now has a payload to Pluto listed (2900 kg.)

            Which page? I can’t see a reference to Pluto.

          • fcrary says:
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            Leaving the hatch off is a bigger deal than you might think. The closed hatch provides some mechanical support for the structure. With an empty hole, more of the load would be carried by the hull. Probably not enough to make a difference, but enough that someone would have to check and possible repeat some tests. Do the vibrational modes change? Probably, but again, probably not by much. But that would also have to be checked and perhaps additional vibrational tests would be required. The spacecraft is designed for months of storage in space, but is that months with the interior in vacuum? That’s a different thermal environment, at the very least, and additional testing and analysis.

            I’ve heard some NASA employees react to similar changes, by feeling the whole thing’s TRL should be dropped from 7 to 5, with all the retesting and re-qualification that implies. Most wouldn’t be that extreme, and I suspect SpaceX would not be either. But it would be more work than leaving off the parts and hoping everything will be fine.

            In terms of funding, I’m not seeing much in the way of self-funding. That’s normally limited and spent to put the institution in a better position to get future contracts and grants. Other than that, I think, we’re more or less in agreement. If you can get the costs low enough, you could probably find the money. NASA might be convinced to something along the lines of their current CubeSat work; if it’s cheap enough and while it’s still a novelty, universities could hit up rich alumni.

            The Pluto reference isn’t on the services/comparison page Keith linked. It’s on the main page for the Falcon Heavy, at the bottom of the section with a black background,
            http://www.spacex.com/falco

          • Paul451 says:
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            Thanks for the Pluto ref. I had looked at that page but completely glossed over it.

            The closed hatch provides some mechanical support for the structure. With an empty hole, more of the load would be carried by the hull. Probably not enough to make a difference, but enough that someone would have to check and possible repeat some tests.

            The hatches and surrounding structures are active functional systems, not passive structures like a door-way in a building. Other than air pressure, I strongly suspect they are not intended to be structurally load-bearing because of the risk of warping/binding.

            Additionally, Dragon is now designed around two completely different types of hatches, the larger berthing hatches and the smaller docking hatches. SpaceX would have needed to know the baseline forces on the opening in order to switch from one hatch-type to another.

            Hence, it will already be a known quantity. Along with engineers already experienced in designing hatches for that opening.

            And, as I said, a one time jettisonable cover will be a much easier engineering task than trying to modify a manually operated berthing hatch to allow automatic operation.

            [Secondary “source”: I’ve heard reports of one of a senior capsule designer/engineer being asked about Red Dragon missions deploying rovers through the side-hatch and casually handwaving that they can “enlarge the side-hatch”, like it was no big thing. And in that case, they are talking about modifying the pressure-vessel itself. I suspect they have a high level of confidence in their design process.]

            OTOH…

            The spacecraft is designed for months of storage in space, but is that months with the interior in vacuum? That’s a different thermal environment, at the very least, and additional testing and analysis.

            …this is true.

            But since they’re floating the idea of Red Dragon, they’ve presumably already considered this and consider it solveable by 2018.

    • SpaceMunkie says:
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      Its that shrinking down effort that lets you make phone calls from something the size of stack of 3×5 cards, carry your computer around, take high quality pictures, ….

      • Mark Friedenbach says:
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        You really believe that shrinking electronics is due to NASA?

        • SpaceMunkie says:
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          who do you think funded all the research? Private industry is concerned with one thing – profit. NASA and DoD are behind 99% of all technology research funding.

          • fcrary says:
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            Definitely not. NASA is currently benefiting from the personal electronics industry, not the other way around. The amount spend on high-capacity, low-mass/volume batteries is enormous, and it’s coming from smart phone manufacturers, not NASA. I’m quite happy to use those Li-ion batteries on spacecraft, but the research finding was motivated by marketing better personal devices. The same is true of microprocessors (high-end scientific computing owes quite a bit to sloppy software design: It creates a market for faster and faster chips, and motivates Intel to spend quite a bit on research and development.)

            Remember, for NASA $2 billion over twenty years is a flagship mission. For Apple, it’s $100 million a year, or 0.15% of their operating income.

          • duheagle says:
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            Agree. I would add that supercomputing is now even more the primary beneficiary of consumer electronics research than NASA. Given the kinds of problems modern supercomputers are generally used for, the fact that they rely more and more on Nvidia silicon than the Intel variety just makes sense.

          • SpaceMunkie says:
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            you have no idea what you’re talking about,
            microelectronics, communication, rechargeable batteries, all of that was driven and funded by the needs of NASA and DoD

          • fcrary says:
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            I’ve been following those technologies, as a professional interest, for about twenty years. The original research and development was largely government funded, but both funding and progress was limited. When a commercial market developed, things really took off.

          • SpaceMunkie says:
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            twenty years is nothing, look back the last 70 years

          • Mark Friedenbach says:
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            Who? Sony. Toshiba. NEC. Fairchild. Intel.

            NASA funding is a miniscule drop in the bucket compared to commercially driven R&D, both historically and today. What you claim is an easily disbunked myth.

  4. Bennett In Vermont says:
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    Truly awesome to see. Thanks Keith.

  5. ThomasLMatula says:
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    This is what American industry has been doing for three hundred years. It was no accident the first American ship to sail around the world, the Columbia, was financed by venture capitalists and made money doing so. Nor that the American frontier was opened up and developed by entrepreneurs.

    If you read the old Robert Heinlien stories, or even Arthur C. Clarke, this was how the first space missions were supposed to be done. Private firms seeking profits. But then the Cold War got in the way with the space race. It is about time we are returning to the model that gave America the most innovative and successful economy the world has ever seen.

    • SpaceMunkie says:
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      Nobody ever held back private industry from exploring space on their own dime, the problem was and still is that thew same companies use the government effort as a cash cow, endlessly postponing and delaying deliveries of parts, underbidding and then asking for more money, …

    • Bernardo de la Paz says:
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      “Cold War got in the way with the space race”?
      Had it not been for the technology investments of the Cold War, (& WWII) space flight would still be limited to Goddard’s rockets and vacuum tube electronics.

      “It was no accident the first American ship to sail around the world, the Columbia, was financed by venture capitalists and made money doing so.”
      Using technology and infrastructure to build and sail ships that had been developed over many centuries, primarily by the various navies of the world.

      “It is about time we are returning to the model that gave America the most innovative and successful economy the world has ever seen.”
      Nothing ‘we’ are doing is or ever has been standing in the way of doing so. Only lack of interest on the part of private investors. There is no public policy impediment to private investment in spaceflight. Lack of government funding of private contractors is not the same thing.

      • Paul451 says:
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        It was no accident the first American ship to sail around the world, the Columbia, was financed by venture capitalists and made money doing so.

        Using technology and infrastructure to build and sail ships that had been developed over many centuries, primarily by the various navies of the world.

        Not arguing against you. The govt-vs-private argument is pretty silly no matter which side you are defending.

        However, I do note that almost all major European exploration was conducted by conventional ships with only minimal modifications. Whether it was Columbus or Cook, or even the Vikings. They never designed custom ship classes solely for a small handful of missions to a particular destination.

        It’s not hard to see the reasoning why the latter would have been a terrible idea and slowed European exploration down by centuries. The logic is simple and obvious…

        And yet…

  6. Zed_WEASEL says:
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    Well to use the Falcon Heavy to launch payloads beyond Mars will take a little longer. It will have to be certified to carry nukes (RTG aka: radioisotope thermoelectric generator) first.

    • fcrary says:
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      Discovery-sized missions can be done at Jupiter with solar power. The cost and payload capability of a Falcon make that attractive. I don’t think the Falcon 9 is allowed for the current Discovery selection, but I suspect it will be in the next.

      • Zed_WEASEL says:
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        Actually yes and no. Solar power is variable at Jupiter orbital distance. But solar arrays degrades rapidly within the Jupiter’s radiation zones. That is why the Juno mission is so short even with the radiation avoidance orbit. Never mind the low electrical energy available, which curtails observations by the instruments..

        • fcrary says:
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          Actually, I was thinking of a Jupiter mission staying more than 15 Jovian radii from the planet. So radiation isn’t a major issue. Also, Juno isn’t limited by radiation in the way you suggest. The limit isn’t the dose on the initial orbit. It could probably last two or three times as long if it could stay on that orbit. The limit is that the orbit will precesses and move it out of the initial, “radiation avoidance orbit.”

          Also, solar flux, and therefore solar power, is pretty constant at Jupiter. The orbit isn’t too eccentric, there aren’t any clouds in the way, and for certain missions, eclipses are easy to avoid. Other than degradation of solar cell efficiency, I don’t see other sources of variability.

  7. Ben Russell-Gough says:
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    I’ve long been of the opinion that the various commercial space companies should be co-operating with sourcing non-satellite cargoes (things like Dragonlab and getting experiments too far to the back of NASA’s queue into lunar and Martian surface and orbit). Maybe set up a brokerage agency that reaches out to academia and ‘rich thrill’ tourist agencies. All companies that provide similar services can quote prices for interest sourced by the agency.

    • Paul451 says:
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      Who else is offering a standard, off-the-shelf lander?

      What you suggest is something that SpaceX should be doing, but not something that requires a co-operative brokerage agency.

      Given the lack of interest in DragonLab, I’d suggest that either SpaceX isn’t very good at selling these ideas to academia & second-tier foreign space agencies, or else current science funding for space missions is already so deeply tied to existing space agencies that small teams can’t get both money and approval to use SpaceX.

      Eg, European or Canadian space-research team can’t get funding for their instruments, unless its part of an ESA mission. Because that is the funding process. (Ditto, US, Japan, etc.)

      If SpaceX were in a better position (reusable cores and capsules, much higher launch rate), they might launch a handful of self-funded missions, and let researchers fly their instruments for free. Ie, the teams only have to fund their own hardware. That’s within reach of internal university funding (and small space agency teams who are funded to for basic tech research, not flying missions. They’d pretend it’s a “test of the hardware”.) Do that a few times and it might be enough to change the assumptions of the game, and agencies will start to fund their own missions.

      (I’m hoping they do that with Red Dragon.)

      • fcrary says:
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        “current science funding for space missions is already so deeply tied to existing space agencies that…”

        Current funding is deeply tied to funding agencies. Although not necessarily NASA. In the US, NSF and NOAA have funded some work. But, in general, universities do not fund research. They preform research funded by outside contracts and grants. Internal research money isn’t very substantial. Although I suppose, if you could get the costs down below a million dollars, donations from rich alumni might become a potential source of funding.

  8. SpaceMunkie says:
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    question: why does it say in the top half that for GTO up to 8mT (8000kg) …. and then it shows performance to GTO of 22,200kg?

  9. John Thomas says:
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    If they charge $62M for a F9, why did they charge $83M for a GPS launch? I wonder what the extra $20M is that the AF is getting for that launch?

    • numbers_guy101 says:
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      The difference is “Mission Assurance (MA)” that the AF wants (above and beyond the call of duty that a private sector customer would want). In ULA the MA is not “severable” as well as much more expensive (I believe they use that term) or that is, you can’t opt for a basic “commercial” package with some large cost savings. The high prices on the ULA side have been a factor most likely in not getting private sector business, the lack of MA being “severable” only makes matters worse.

      This also happens with NASA, at probably a 10% MA for ISS launches, and we saw an even higher premium for that 1st SpaceX NASA science mission (Jason – see http://www.nasa.gov/home/hq…, adjust for inflation, etc.)

      Notice a more complex payload for DoD (actually a NASA/NOAA payload) went even higher – see – http://spaceflightnow.com/n

      This lends credence to the idea that simpler, more repetitive payloads using Falcon’s would approach commercial rates even for the government (perhaps a 10% or so premium). This could be useful for propellant, repetitive payloads (like the upteenth GPS), and refueling-based exploration concepts for NASA (adding in the spacecraft etc. of course).

    • fcrary says:
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      They charge NASA more than they do for commercial launches. I wouldn’t be shocked if the same thing applies to Air Force launches. NASA insists on more oversight, since they want to make sure things are done right. SpaceX goes along, but passes on the resulting extra costs. Commercial customers just buy insurance and let SpaceX do the job (well, not completely, but the customer’s involvement isn’t as extensive.)

      • Bernardo de la Paz says:
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        Nope. The main difference is that NASA is paying for the Falcon launch plus the Dragon to ISS versus the commercial missions paying only for the Falcon launch.

        • fcrary says:
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          That’s an interesting point. Does NASA buy the Dragons used on a resupply run, or do they just rent them? SpaceX has recovered half a dozen so far. Does anyone know where they are or who owns them?

          • Bernardo de la Paz says:
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            None of the COTS Dragon’s are to be reused. But whether bought or rented, the fact remains that COTS is paying for a much more complex mission than other launch customers, which is the main cost difference driver.
            The question you should probably ask is how much has NASA paid for non-COTS flights on Dragon (e.g. Jason 3) compared to other launch customers. Quick search says $82m: http://www.nasa.gov/home/hq
            for launch plus plus “additional services under other contracts for payload processing, launch vehicle integration, mission-unique launch site ground support and tracking, data and telemetry services.” Given the unique, one-time payload integration and the Vandenberg launch, it’s pretty easy to see where $20 goes, but I don’t know how to find an official breakout of just the launch price. The SpaceX page says the $62m is for standard mission costs to GTO. It would be interesting to see what the DSCOVR launch cost was, but I haven’t been able to find anything.

          • Paul451 says:
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            None of the COTS Dragon’s are to be reused.

            The contract only specifies that they CRS flights themselves must be new capsules. It doesn’t say that SpaceX can’t reuse the recovered capsules for other customers.

            (Of course, currently there are no other customers, so potato, potato.)

          • fcrary says:
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            That was sort of what I was thinking. If SpaceX can reuse them for non-NASA customers, then they might be willing to give NASA a reduced price. (Or not, as they see fit.)

            But I was also curious for historic reasons. Recovered spacecraft tend to end up in museums. I was wondering who picks the museum, NASA or SpaceX?

          • Paul451 says:
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            The capsules are returned to SpaceX, and there’s no SAA where SpaceX is “allowed” to retain the NASA-property for post-mission testing under some kind of data-sharing arrangement. That suggests that SpaceX retains ownership of the hardware.

  10. Bernardo de la Paz says:
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    At last, somebody has finally answered the question I and others keep asking here – why send people to Mars? Colonization could be a pretty good reason. IF it could work.
    The reality is that the red planet is a red herring as far as colonization goes. The atmosphere of Mars is simply too thin to support colonization. Even if you could build a substantial economy living under artificial pressure domes, the atmosphere is too thin in relation to Mars’ gravity to enable an economically viable transportation infrastructure to the surface of Mars with known or foreseeable technologies. (Red Dragon can only land payloads in the same class as the Curiosity rover and does not scale up well to larger sizes.)
    Presumably colonization goals are still assuming some sort of terraforming scheme as proposed by Carl Sagan. Whether using some sot of genetically engineered oxygen generating microbes or nuking the polar ice caps, all Martian terraforming plans are doomed by a common fatal flaw. Mars has no magnetic field and so the solar wind will simply blow away whatever atmosphere is created. Perhaps if it was created fast enough it could exist for a little while, but what use is that and how could it possibly be economically viable?
    The reality is that Mars is a dead planet and a dead end and all the other planets in this solar system are even less suitable for colonization.

    Gerard O’Neill and the L5 Society had it right long ago. If mass population of space is the goal, then free floating colonies are the only viable answer in this solar system and the planets should be bypassed. Unless somebody invents a way to overcome the limitations of Einsteinian physics on interstellar travel, the goal of planetary colonization is a misguided waste of time.

    • fcrary says:
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      Not that I take terraforming plans too seriously, but I wouldn’t worry about atmospheric loss. The current estimate, in the PR sound bite version, is about the mass of a hamburger per second (0.1 kg/s ~ 1/4 lbs/s). There is every reason to believe that was orders of magnitude higher in the past, but unless you’re concerned about terraforming lasting for a billion years, you don’t need to worry about this.

      • Bernardo de la Paz says:
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        That rate applies to Mars’ almost non-existent current atmosphere. If the atmosphere was thicker, the loss rate would be higher. Then there is still the problem of no magnetic field to provide radiation protection. I agree that terraforming is barely more plausible than faster-than-light travel, but even if it were possible to thicken the Martian atmosphere, the plan still fails in the end. In the game of colonizing space, Mars is a fool’s errand.

        So, back to the original question. Why send people to Mars. I still see no answer other than flags & footprints, which will be good for about one mission. In the meantime, Mars mania is sucking up resources from making progress in more productive directions.

        • fcrary says:
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          I don’t think the atmospheric loss rate depends on the surface pressure (well, not strongly.) I frequently see papers comparing Venus and Mars, and assuming the main differences affecting the loss rate are solar wind conditions and solar UV flux.

          The loss is really driven from the top down. Below some altitude (pressure level), the atmosphere is not significantly affected by the solar wind or solar UV. All the loss comes from above that altitude, so (to first order) it doesn’t matter how much atmosphere is below that altitude (above that pressure level.) There are some more subtle points, like the temperature profile and the vertical distribution of water, but it isn’t like doubling the surface pressure doubles the loss rate.

          In the case of Mars, it looks like the rate varies considerably with solar wind conditions, and the young Sun was considerably more active than it is now.

    • Paul451 says:
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      Mars has no magnetic field and so the solar wind will simply blow away whatever atmosphere is created.

      If you have the industrial capability in space to basically construct an entire planetary atmosphere from scratch, you have the capacity to do maintenance on what you built.

      I don’t disagree that Mars is a bad destination, nor that terraforming is stupid, just that this is not a “fatal flaw”.

      Gerard O’Neill and the L5 Society had it right long ago.

      No they didn’t. Building giant cities in orbit is just as unrealistic as colonising Mars.

      L5 Society fantasised about giant space cities at L5 and then tried to back-formulate a reason for the space-cities to exist. Exactly like the Mars fanatics.

      (IIRC, L5’s reason was to house a workforce for SPS construction from lunar resources.)

      It’s backwards.

      The form of space settlement will follow the use of space. That’s where people will live. If there’s something to do on the moon, people will end up living mainly on the moon. If there’s something to do on Mars, then and only then does settlement made sense. If the whole asteroid-mining idea takes off (so to speak), then people will live in mining towns inside the asteroids.

      It doesn’t matter if these are not the most efficient or perfect locations for settlement, it’s just where people will end up. Same as cities on Earth. We didn’t build them at the best places to construct a bunch of urban infrastructure, we built them were it made sense to have a bunch of people: Deep water ports, rivers, transport cross-roads, agricultural hubs, etc.

      (A century later, people deal with the fact that the site is usually a terrible place to grow a city. Swampy soil, flood-prone, space-limited, etc.)