Video: Deep Space Industries David Gump on Asteroid Mining

21 Comments

Deep Space Industries CEO David Gump talks about asteroid mining.

  • Michael Vaicaitis

    First of all let’s make it absolutely clear: an air launch aeroplane is NOT NOT NOT a reusable first stage. What it is, is a mobile launch pad. Lifting the rocket to altitude and to 500-600mph increases the payload to ORBIT!!!!, by only about 5%. The effort of reaching orbital altitude takes only 7-9% of the launch propellent. The other 91+% of propellent is used to reach orbital “velocity”, and a lot of the initial velocity imparted by an air launch is vectored in the wrong direction for reaching orbit. It would be cheaper and more effective to build a launch pad at high altitude and near the equator.

    In stating a business plan based primarily on the cost of lifting materials (mainly propellent & water) he gives the impression of entirely failing to correctly analyse the fundamental problems that have led to high launch costs. Manufacturing propellent (and water) on Earth is easy and cheap. Lifting it to LEO or beyond is a matter of designing cheap, meaning reusable, launch systems. Developing asteroid (or lunar) based fuel manufacturing will cost tens or even hundreds of billions. The only way to reduce the cost of that process is to develop cheap reusable launchers, but when you have cheap reusable launchers, the economics of building large scale industrial complexes beyond Earth orbit diminishes considerably.

  • Kapitalist

    Air launch has the advantage of flexibility. It can fly to where there is good weather and could launch from any part of the world. And for *sub-orbital* launches your altitude/velocity figures would look better. But it is not the big solution for mining asteroids.

  • Michael Vaicaitis

    “Air launch has the advantage of flexibility.”
    Exactly, it is a mobile launch pad and so reduces or removes many of the range issues with a static pad. The downsides are: 1) that you need to spend an extra gazillion dollars on the aircraft compared to a launch pad, 2) you can only build an aircraft so large, which restricts and limits the size of rocket and thus the mass and volume of payload, 3) you can’t check engine performance after ignition and before releasing for launch, so human passengers would be a difficult sell for orbital systems, 4) more difficult to handle propellent pressures between fuelling and launch.

    The only advantage of air launch for orbital launches is range flexibility.

  • Tonya

    I think from some of the numbers I’ve seen for air launch, there’s a bigger performance gain from having an optimized engine (lower air pressure) than altitude and velocity. That may well be a viable route for small launchers, of 500->1,000 kg payloads, but once scaled up it seems to run into practicality and cost issues quicker than the benefits.

    The simple reason why Paul Allen is building a really big plane, is that he asked the advice of a man who builds planes. It may work, it may even be cost effective, but I’m fairly certain that it won’t ever scale up any further.

  • Kapitalist

    The military market likes flexibility and isn’t price sensitive…

    I think an important point to remember here is that Branson owns an airliner and has a talent for marketing. Sub-orbital microgravity tourism followed by trans-oceanic rocket flights fit his business, image and technology better than does putting payloads into orbit.

  • Michael Vaicaitis

    Yeah, the military are in the business of spending as much money as possible to justify their existence.

    Sub-orbital is an expensive fashionable joyride. Perhaps useful for smaller companies to get a start right now, but a don’t much of a long term future in it.

  • Michael Vaicaitis

    Quite so, it’s the slight improvement in engine performance and a reduction in total ascent drag that gains the extra 5% to orbit. The altitude in and of itself is only a very marginal help and the aircraft velocity is hard to translate into orbital ascent velocity.

  • Kapitalist

    Well, it does benefit space related technology development and public attention, especially if the famous Mr. Branson himself actually becomes the first passenger in his own microgravity rocket-plane. It is getting fashionable for rich people to invest in or consume space related services for billions of dollars, and that doesn’t make me complain. Btw, airlines won’t always fly in sub-sonic speeds, I’m sure Virgin is investing in Galactic in order to push ahead for the airplanes of the future when net profits will be much higher per seat than they are today per jumbojet.

    TED Talks is a very stressful and over-hyping format. Trying to squeeze in sub-orbital together with asteroid mining. I prefer real lectures or interviews. But still, it gets some public attention and that is badly needed for space to take off again.

  • Aerospike

    Could you please elaborate more on the issue you seem to have regarding to “aircraft velocity being vectored in the wrong direction”?
    You state the flexibility of a “mobile launch pad” as the only real advantage of air launch, yet you seem to ignore the fact that you can have your plane flying in exactly the right direction to maximize the available speed boost (I know it is still too low to be a real benefit, but I just don’t get your “wrong vector” argument).

  • windbourne

    Which is why it seems me like the smart thing is to get it up around 70-80K with a speed of mach 2-3.
    Considering that we have the ability to do that with the XB-70, why not do it then?

  • Michael Vaicaitis

    Unless you’re a Skylon and you want to stay in the atmosphere breathing air for as long as possible, then you want to get out of the atmosphere as soon as you can. This means a steep ascent profile. Since the rocket must be away from the aircraft when it fires, it must drop away from the carrier aircraft. This means that the aircraft cannot be angled along the ascent trajectory at release and even if it were a considerable amount of the velocity along that vector would be lost in the few moments before the rocket becomes self-propelled. This all ends up meaning that the rocket starts off with a relatively shallow, if not horizontal, trajectory. It then has to perform a high g turn toward vertical for the ascent out of the atmosphere and on to orbit. As an example a Pegasus has small wings and tail fins for the turn manoeuvre.

    If you’re a sub-orbital “space plane” such as SS2, then aerodynamic lift and a low ascent g is an advantage. Especially considering the wings/lifting-surfaces will also be used on the way down. For a rocket going to orbit any benefit of lifting surfaces is extremely short lived in relation to the rest of the “ascent”.

  • Snofru Chufu
  • Michael Vaicaitis

    Assuming the angle is for real and you’re happy to ignite the rocket engines in close proximity to the aircraft, they maybe you’re right. I do wonder though the speed and angle of attack of this rocket when the engines fire.

    I’m guessing though that this is not a orbit capable rocket capable of lifting several tonnes of payload to LEO. Also, that aircraft doesn’t look much like two 747’s glued together.

    The suggestion implied in the video is that air launch reduces the cost of access to space by taking the rocket part of the way and that therefore the aircraft can be considered as a reusable first stage. Such statements are either misguided and/or ridiculous misinformation. My argument is that the carried aircraft does not qualify for the title of “first stage” and should much more accurately be labelled “mobile launch platform”. Furthermore, it is all but certain that an air launch system will be more expensive than a launch pad and vertical launch rocket and so actually increases the cost of access to space.

  • mzungu

    I can see water exists on the asteroid belt and on comets, because they spend most of there life so far away from the sun, but can someone explain to me how water can exists on NEO when they are baked constantly so much closer to the sun? the NEO either have to be spinning in some funny ways to have constant shadows, or be so big that it’s core can remain frozen….

  • mzungu

    The thing is that flexibility is handicapped by the payload, the satellite, which take years to build . which render any flexibility null. Having a bunch of small military satellite sitting around getting outdated so you can launch on demand don’t make much sense.

    The only use for this kind of launch-on-demand capability is pretty much ASAT. US already have that low-orbit ASAT capability with the ASM-135 and the AEGIS Standard missile combo, which I will assume there is a few lying in some secret warehouse.

    What USAF currently want is to knock off medium orbit Chinese/Russian navigation satellites, which will explain some of the recent DARPA request for larger payload air-launch proposals.

  • Snofru Chufu

    I personally think that airlaunch is only an adequate approach for (mainly solid propellant propelled) small launch vehicles in a range up to few tons, where air resistance play a significant role. For very small launchers (of a few hundred kg) it i smay the only alternative.

    Yes, the most important aspects of this kind of launch it are flexibilty and missing need of a certified launch range (because you can do it easily above sea). I think the launch from a platform stationated in sea, 15 miles away from shore, may a good alternative for launch from ground.

  • Snofru Chufu

    Yes, I think also the use of an aircraft for larger launch vehicles brings to much constraints and restrictions.

  • Snofru Chufu

    That is correct, you need air lauchned small launchers at first, if you would like to use it as a stand-by weapon or military explorer.

  • Aerospike

    I see your line of thought now, but I would still argue that you are not correct. Again I’m not trying to make a point here for some mythical desirable initial speed boost by air launching. Any velocity benefit (if any at all) will be quite small. So this is just an argument about the principal physics behind it.

    So… by following your arguments, one would have to come to the conclusion, that there is also no speed boost to be gained from launching closer to the equator! Because that velocity vector (Earth’s rotation) points “exactly” in the same direction as your rockets initial speed when airlaunched (assuming a launch from the equator to geosynchronous orbit in both scenarios). Therefore it is perpendicular to the initial direction of your rocket after launch, just like your example about air launching.

    You said so yourself, that “going up” is not the relevant part of reaching orbit. So how is the need to go vertical to leave the atmosphere (the thickest part being already below you in case of air launch) invalidating the initial horizontal speed of your rocket (which ultimately is the only thing that counts for reaching orbit)?

  • Michael Vaicaitis

    The difference is that air, and gravity, resists an upward change of vector, whereas in space, gravity will put you in the orbit that matches your speed.

  • Snofru Chufu

    You can study the effect of air-launch quite good by comparing Pegasus and the from it derived launcher Taurus: Taurus has 4 stages (one is added to the Pegasus stack) und Pegasus therefore 3 stages. However, the payload mass fraction (for example for low LEO) fraction is nearly same!! Pegasus: 1,9%, Taurus: 1,8%. So air-launch may simply a system, but does not increase performance signifcantly, if you can add the saved stage again.