SpaceX has brought down the price of delivering payloads to low earth orbit to under $3000 per kg, but even a small satellite still costs over $1 million. A company called SpinLaunch proposes to lower costs further by flinging the things into space on a giant centrifuge. At a certain altitude, a small booster engine would ignite, accelerating the payload to the 7 miles per second needed to achieve orbit. We don’t know how practical or realistic this proposal is, but this video is worth three minutes of your time.

16 COMMENTS

  1. A space shot-put!
    More practical than artillery, but achieving the precise timing needed for the successful operation of the projectile’s release mechanism would be… a challenge.
    An additional challenge would be the projectile’s survival of flight through the low atmosphere, at nearly escape velocity. Max Q would occur immediately after release. Perhaps if the launch site were atop Mount Everest…
    Just thinking…
    A fun story, Russ. Happy May Day, komrad! 😉

  2. If we can dream this stuff up, we can engineer it to work. Is cheap satellites what we really need? Elon is launching 10,000 plus for one project. Pretty soon we will global warming under control by the massive sunshade of satellites over our heads.

      • Certainly concerning.

        There are schemes to grab and remove satellites.

        McDonald Detwiler company had one, building on the space shuttle’s manipulating arm it had purchased.

        But government’s jerked the company around (Canada blocked sale of products to the US on ‘national security’ grounds) and ownership has flipped around lately. Still has the manipulator product line, collaborating with NASA.

        Another company started by smart people, did well (I knew a couple of its early engineers), but faltered somehow. Founders would be very old now if alive.

        OTOH, there are schemes to include a drag producing device in satellites to de-orbit them after several years (but where will they fall?).

    • The centrifugal force is in the hundreds to a few thousand Gs depending on the dimensions and how much of the energy to reach orbit is provided by the flinger vs. the “small” booster engine. The payloads will inevitably be heavier in order to withstand the much higher G loads than would be seen in a normal rocket launch.

      • What they appear to be aiming for is 5,000 mph and a 150 ft radius. That is 2235 m/s and 46 m for over 108,000 m/s^2 or 11,000 G!

        So the payload has to withstand insane acceleration and then several seconds of insane friction through the lower atmosphere at an initial speed of 5,000 mph. And it has to include the rocket to get it the rest of the way to orbit. I do not expect this will ever be practical on Earth.

        Now if you want to send stuff back from the moon or even Mars, maybe this would make sense.

  3. Isn’t Earth’s escape velocity about 7 miles per second with an orbital speed of around 5? Also, I wonder about the unbalanced load on the spinning radius arm mechanism after the missile is released.

  4. If your concept doesn’t violate any laws of physics, then quite likely it is in fact possible…just an engineering problem, as they like to say. The big question is, will it be practical?

    In this case, assuming they can make it work, it would be competing with the likes of Space-X and their reusable boosters that can launch 40 or 50 of these small satellites in one go and do it more gently to boot (or boost, ha). Hard to see them beating the per-satellite cost Space-X can offer. Is there a huge untapped market for on-demand one-off launch of mini satellites that would compensate?

  5. I find this so odd. I love aviation, and also a CFI, but find space so boring (sorry), but I hopefully find those that seek it find what they excites them. Yes, we always need discovery.

    • The demonstration was pretty far in scale from the actual goal. With the numbers given in the article they demonstrated it with about a 1200 G centripetal acceleration. That’s impressive, but their goal is closer to 8600 G. The concept is pretty simple, but I do not believe what they have shown so far says anything about how practical this will be.