[HN Gopher] NASA will test SpinLaunch's ability to fling satelli...
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NASA will test SpinLaunch's ability to fling satellites into orbit
Author : clouddrover
Score : 99 points
Date : 2022-04-11 23:41 UTC (2 days ago)
(HTM) web link (newatlas.com)
(TXT) w3m dump (newatlas.com)
| culopatin wrote:
| Could we use this to launch radioactive waste into space at
| higher speeds than what's needed to remain in orbit?
| dotnet00 wrote:
| It would still need a rocket to prevent the waste from coming
| back around and striking the launch site. To not have it come
| back, it'd need to be shot out at Earth escape velocity
| (there's also the option of shooting it out fast enough for the
| Moon to offer an assist to put things into orbit).
|
| Although of course that fast of a throw from within the
| atmosphere is probably not practical.
| [deleted]
| SapporoChris wrote:
| No. Escape Velocity (https://www.wikihow.com/Calculate-Escape-
| Velocity) is: 11.2 km/s.
|
| From the article, they've only achieved 8,047 km/h or 2.23
| km/s.
|
| Also, flinging waste from your home into the air and hoping it
| won't come back down sounds like a really bad idea.
| jdmichal wrote:
| Just for giggles, that works out to ~17.42 kilowatt-hours per
| kilogram of mass, just for the pure kinetic energy. Then you
| have inefficiencies like electricty-to-kinetic-energy
| conversion losses and atmospheric drag to contend with.
|
| It's honestly a smaller number than I expected it to be. So I
| suspect that those inefficiencies add up pretty fast.
| throwmeariver1 wrote:
| With the extremely limited resources of earth we can't just
| throw something into space without knowing if there could be
| any future use.
|
| Where did we put the energy dense radioactive stuff again? We
| could use it... Sorry boss we yeeted it into space.
| endisneigh wrote:
| With these sorts of technologies I wonder if it just makes more
| sense to lay whatever needs to be paid to build a space elevator
| or equivalent and be done with it.
| pstuart wrote:
| Isn't there still the small problem of actually having the
| technology exist to do it?
| Arainach wrote:
| What makes you think the problem is money and not materials
| science? We have no substance suitable for the cable. The
| closest we've come is various nanofilaments that we can perhaps
| produce in centimeters, not kilometers.
| endisneigh wrote:
| I agree that the problem is materials science. My point is
| how much money is actually being allocated towards that vs
| sending stuff in space, to what end?
|
| I don't follow material science stuff super closely but as
| far as I'm aware the investment is orders of magnitude less
| than propulsion and other tech.
|
| Then again these things just take time unfortunately
| zardo wrote:
| I recall excitement that
| https://en.m.wikipedia.org/wiki/Colossal_carbon_tube were
| just the ticket. But since there has been zilch published on
| them in the last 14 years, I'm guessing the original work
| couldn't be reproduced.
| bluescrn wrote:
| Because every fictional space elevator seems to end in
| disaster?
| [deleted]
| ada1981 wrote:
| Coolest part of this company is the founder is a (i think high
| school) drop out who read some physics books and thought "this
| should work." Have spent some time with Jonathan on MajikBus.co
| and I appreciate the way his mind works.
| green-eclipse wrote:
| Here's video of a test launch from their website, if you're
| curious:
|
| https://www.spinlaunch.com/suborbital
| honkycat wrote:
| Everyone called me crazy when I said eventually we will start
| shipping things by dropping them from orbit.
|
| This is the next step in my genius idea with 0 flaws or potential
| disasters
| Havoc wrote:
| Kinetic bombardment has been a thing (conceptually) for a
| while.
|
| >potential disasters
|
| unless that's the intention
| FpUser wrote:
| I can only imagine what a spectacular show would it be if the
| load unclips at the wrong moment.
| h2odragon wrote:
| Every time i see their thing i wanna build another centrifugal
| BB cannon.
| DrBoring wrote:
| Reminds me of the centrifuges that people would build for Pumpkin
| Chunkin, a competitive pumpkin throwing contest from Delaware,
| USA.
|
| https://www.youtube.com/watch?v=p2GeuWqNXWU
| hitovst wrote:
| How many Starship launches does it take to get SpinLaunch to the
| moon, belt, etc.?
| thedrbrian wrote:
| You'd just put a mass driver down
|
| https://en.wikipedia.org/wiki/Mass_driver
|
| That way you can also launch people without having to subject
| them to thousands of G.
| gorgoiler wrote:
| As Kerbal Space Program has taught me, it's all very well
| reaching ballistic apogee but you need to apply thrust again at
| apogee to circularize orbit (raise your perigee to the same
| altitude as you are right now.) Otherwise you'll just come
| straight back down again.
|
| How can this device fling a functioning rocket motor into space?
| dmead wrote:
| staged rockets also fling rocket motors into space. /shrug
| boardwaalk wrote:
| ...at _maybe_ 10g, not 10,000g.
| colechristensen wrote:
| Rockets already have to withstand some pretty extreme
| structural challenges. The spinning would certainly involve a
| bit of a different challenge but not necessarily out of scale
| for things they already have to survive.
| jeffwass wrote:
| I think launch angle can be adjusted, it's just straight up for
| the photo. Eg, see the rendering further down the page on the
| grassy hill which shoots at an oblique angle.
| gorgoiler wrote:
| Your periapsis -- the lowest part of your orbit -- is always
| the place you return to. Throwing harder or at a different
| angle just determines how high you get when at your highest
| point, before coming all the way back down again.
|
| http://www.scielo.org.mx/img/revistas/rmaa/v52n2/0185-1101-r.
| ..
|
| If you apply thrust at A then you have the solid line: an
| elliptical orbit.
|
| If you just throw something hard all you have is the dashed
| line: go up then come back down again.
|
| (In this diagram, substitute "initial circular orbit" for
| "surface of Earth" :)
| Symmetry wrote:
| That's why spinlaunch is flinging a whole rocket high into
| the air rather than just the payload.
| sidewndr46 wrote:
| This isn't the case at all. The trap your reasoning falls
| into is assuming that for some reason an object must be in
| an orbit after being thrown. Obviously, an orbit comes back
| to it's original position at some point. In many cases
| atmospheric drag converts what would be an orbit into
| burning up in the atmospheric or smashing into the ocean
| somewhere.
|
| But if you throw something hard enough from the Earth's
| surface, it absolutely does not have to return to that
| position. You would just need to throw it hard enough that
| it was at escape velocity. Due to air friction, the actual
| speed you would need to throw the object would be flat out
| absurd if on Earth at sea level. But on a body like the
| moon with no atmosphere it isn't that bad at all. The bonus
| to this is the direction doesn't matter at all really.
| Anything other than straight down is fine.
|
| Now, where this does become problematic is when the
| velocity you would need to achieve is higher than the speed
| of light. At that point you're basically on a neutron star
| or some supermassive planet.
| obblekk wrote:
| 10,000Gs is probably too much for electronics, but fine for raw
| steel. Probably useful to have a low cost way of shooting a lot
| of working material into space.
| __init wrote:
| They made _vacuum tubes_ survive 20,000g during WWII [1].
| Modern military applications have guidance computers packed
| into individual bullets [2]!
|
| [1]
| https://en.wikipedia.org/wiki/Proximity_fuze#Improvement_in_...
|
| [2] https://en.wikipedia.org/wiki/Smart_bullet
| modeless wrote:
| The problem with this is if you toss a chunk of raw steel, no
| matter how fast or at what angle, it will always simply fall
| back down [1]. The minimum payload for this system absolutely
| requires a (extremely robust) rocket engine and propellant and
| avionics to circularize the orbit at apogee. That's the only
| way to achieve orbit. That puts a disappointingly high floor on
| the cost per launch and launch rate.
|
| [1] Technically, escape velocity is also a possibility. But
| it's not a useful one, as the payload is still lost.
| nottim wrote:
| That only holds true assuming a 2-body (earth and rocket)
| system - add in forces from the sun or from the moon and you
| can actually achieve orbit with only a single surface level
| impulse, although it does require some pretty precise aim.
| modeless wrote:
| It would be super cool to use the moon to circularize the
| orbit. But the orbit you'd get wouldn't be super useful,
| probably. I wonder about stability as well. And the
| practicality of achieving the velocity to reach that high,
| and aiming that precisely. It would be really cool to see
| some analysis of that.
|
| Another out-there idea would be to shoot things at a space
| station that had a giant catcher's mitt or something. Would
| it be possible to design a decelerator that would work? And
| to hit it precisely with a dumb projectile from the ground?
|
| A third possibility would be to recover and reuse the
| rocket engines en masse. Not sure how it could be done in a
| way that was cost effective though.
| gchadwick wrote:
| Like many others I was very skeptical of SpinLaunch's claims.
| Even with their successful demo launch you wondered if you'd be
| able to build a viable payload (especially one with a rocket
| motor, not just solid state electronics).
|
| Though if NASA have chosen to enter into a contract them that
| gives a big credibility boost. It'll be very interesting to see
| how it goes.
| belter wrote:
| Hopefully NASA watched this video, before making the contacts
| public instead of first examining the claims privately.
|
| "Spinlaunch: BUSTED!": https://youtu.be/9ziGI0i9VbE
| rozab wrote:
| Richard Woolley springs to mind.
|
| https://en.wikipedia.org/wiki/Richard_van_der_Riet_Woolley#V.
| ..
| raverbashing wrote:
| Ah of course it's thundrfoot.
|
| His phosphine "debunking" video was high on "hot takes" but
| low on actual intellectual honesty
|
| There are ways of criticizing and going about that don't
| involve patronizing and shallow dismissals
| Laremere wrote:
| "Busted" videos like this are low quality armchair analysis
| aimed at giving giving the viewer a sense of intellectual
| superiority. Saying "this solution breaks the laws of
| physics" can be valid if analysis is done correctly, saying
| "this problem is hard, and they haven't already solved every
| single piece of it so their whole business is stupid" is not
| valid.
| arein3 wrote:
| These types of videos have a very wide audience. Redditors
| love them.
| belter wrote:
| I agree with you that the video could be more detailed on
| some of the technical analysis. However it raises enough
| technical arguments, to justify any approach to SpinLaunch
| to be done in private and with a very skeptical attitude.
| JacobThreeThree wrote:
| Presumably NASA, who's paying for test launches, did a
| more thorough analysis than a YouTuber.
| belter wrote:
| Only thing NASA seems to have contracted the company for
| is for a technology demonstrator, of throwing a small
| rocket at Mach 2.
|
| The article describes it like they are throwing
| satellites into orbit. In reality even the far fetched
| plan, is to throw a small rocket into high altitude to
| save money on the first stage. Then the rocket is what
| will put the satellite in orbit.
|
| I can't find a single reference to this agreement (yet)
| in any NASA official site. Not saying it's not real, just
| that I can't find an official NASA reference yet. It's
| not yet listed here under the current available ongoing
| agreements:
|
| "Current Space Act Agreements"
|
| https://www.nasa.gov/partnerships/about.html
| attilaperez wrote:
| Theranos had Walgreens, Nikola had GM...
| belter wrote:
| This analysis also highlights the complexity risks. They
| will need to achieve Mach 10 and have a satellite capable
| to handle 20,000 G...
|
| "Spinlaunch Feasibility Analysis":
|
| https://colab.research.google.com/gist/jeff-
| hemingway/a3d322...
|
| Edit: The HARP project is also mentioned in the analysis as
| a comparison.
|
| https://en.wikipedia.org/wiki/Project_HARP
| Retric wrote:
| 20,000g's sounds much worse than it is. Some WWII era
| guns used ammunition with complex proximity fusses
| subjected to roughly 20,000g's.
|
| The real question is what kind of mass fraction is
| sacrificed to build something to survive being spun up.
| [deleted]
| colechristensen wrote:
| I can't tell if you're joking.
| gchadwick wrote:
| Well I would hope NASA is doing their due diligence.
|
| Perhaps though there's a big push to invest in private space
| and they're not looking too closely at lower value/more
| speculative prospects.
| blackholesRhot wrote:
| FYI I'm a Spinlaunch invesetor.
|
| Just watched this video. His argument for why Spinlaunch
| won't work is basically:
|
| 1) in the video of their first test chamber (12m diameter)
| there's some dirt and rust, therefore they don't know
| anything about vacuums
|
| 2) in their first ever test fire of a projectile leaving
| their 33m chamber, the projectile is wobbling, therefore they
| don't know anything
|
| 3) in a mock up video they made of a future launch system the
| headquarters is close to the launcher, which might explode if
| there's a misfire, therefore they don't know anything
|
| 4) the founder has an uninspiring resume when you look online
|
| 'Add these up and there's no chance they'll succeed. What
| they've done isn't as impressive as 50+ year old gunships.'
|
| Give me a break. Their rate of progress is exceptional.
| They've already overcome so many challenges. These are weak
| arguments. Doesn't mean they'll be successful. But these
| arguments are weak. Some quick counter-arguments
|
| 1-) the 12m test chamber was a demo chamber. they were
| constantly spinning it up and letting people go inside. doing
| tours. stress testing new materials and arms. blowing stuff
| up. if anything the fact that it was so reliable even with
| the imperfections is a positive
|
| 2-) when someone is learning to throw a football there's tons
| of wobble. spinlaunch needs to figure out a perfect spiral.
| these videos were from their first couple attempts ever out
| of a chamber. what they're showing is very hard. this team
| has shown an ability to innovate and improve. those were
| images of their first few attempts to "throw the football"
|
| 3-) give the team some credit. these videos are designed for
| the general public. what they built already has an incredible
| amount of kinetic energy. they stress tested many tethers
| (past their limits) before going to this scale. when you're
| picking on things as small as "they're going to kill
| themselves by sitting right next to the system" you clearly
| don't have much left to nitpick
|
| 4-) jonathan is an absolute genius. just because he has a
| spartan online bio and unorthodox background doesn't mean
| he's not an absolute force of nature. thunderf00t is a very
| smart dude. but i'd bet anything that in a debate -- on
| basically any topic -- jonathan would absolutely decimate
| thunderf00t
|
| cheers to the builders
| [deleted]
| sebzim4500 wrote:
| >thunderf00t is a very smart dude
|
| I just saw one of his videos on why Falcon 9 will never be
| economically viable so I would strongly disagree with this
| assessment.
| belter wrote:
| I think his argument about Falcon 9 was about reliability
| vs reusability and he partially acknowledged he was
| wrong:
|
| https://nitter.net/thunderf00t/status/961312911393218560?
| lan...
|
| About the claim if he is smart or not, you might want to
| watch this then reevaluate your opinion:
|
| https://youtu.be/5Hyy1zRZPiQ
| recuter wrote:
| Smart people make mistakes all the time. He has correctly
| debunked a lot of scams, it is easy to get jaded and
| carried away. Since he isn't an investor and doesn't have
| the inside scoop it is plain to see how his nitpicking,
| based on the publicly available information, potentially
| led him to a wrong conclusion.
|
| SpinLaunch is a rather out there. I've actually had this
| idea and I'm sure many others have as well. I happen to
| think it can work but I was still skeptical when I first
| heard of them. You can only infer so much from the
| outside.
| caconym_ wrote:
| I really hope NASA is making better use of taxpayer dollars
| than paying their decision-makers to watch clickbait trash on
| Youtube. How any serious person could take this sort of thing
| seriously is beyond me.
| dotnet00 wrote:
| I think their basic idea is sound, it'll probably eventually
| function. My concerns are if it'll be worth it, since there's a
| trade-off being made between fuel mass and heat shield mass,
| and at least based on Scott Manley's summary video this week,
| the rocket with the heat shield is close to the same mass as
| the Electron rocket. In which case I'm not sure the complexity
| of SpinLaunch is worth it.
|
| Edit: the video in question:
| https://www.youtube.com/watch?v=8Phy3n_S3ng
|
| and a more honest and detailed look at the company, again from
| Scott: https://www.youtube.com/watch?v=JAczd3mt3X0
| gnramires wrote:
| I haven't seen Scott Manley's video; but if the mass cost of
| a heatshield is so significant that's a problem.
|
| However, there's a benefit in this case: heat shield probably
| scales with area (often something like mass^(2/3)), making it
| progressively less significant compared to fuel mass (which
| is roughly a constant fraction, i.e. it scales like
| mass^(1)). I think a high altitude launch site could make a
| significant difference as well (although that creates other
| logistic inconveniences). Atmospheric pressure approximately
| halves every 5km, and air resistance is roughly proportional
| to pressure.
| colechristensen wrote:
| Launch conditions are already very harsh. Rockets vibrate _a
| lot_.
|
| I have no doubt that useful payloads could be designed to
| withstand the spinning as well as later rocket thrusts.
| (source: a couple of years on a satellite design project in
| university)
| consumer451 wrote:
| One other detail I've learned is that the G load increase is
| incremental, not all at once. Which apparently is very
| significant according to the company.
| ColinWright wrote:
| The G load increase is comparatively slow, but the
| _release_ is pretty sudden.
|
| Lots of things "bounce" in funny ways when you put them
| under very large loads, then release that load suddenly.
| [deleted]
| paxys wrote:
| There is no launch contract, just a planned test.
| MisterBiggs wrote:
| If they can get this working reliably on Earth then I would
| imagine it would work incredibly well in space. Could do (cargo)
| launches from the Moon to Earth with just energy from solar
| panels without any propellant. Probably would be the optimal way
| to put a ton of satellites in orbit of the Sun too for something
| like a Dyson Sphere.
| aw1621107 wrote:
| Conservation of (angular) momentum would mean that you'll need
| at least some amount of propellant to compensate. The
| rotational inertia that's present during/after spinup can pose
| challenges for aiming as well.
| excalibur wrote:
| Are we in an episode of Space Force? Did I die and go to Netflix?
| hilbert42 wrote:
| One wonders how practical this would be given the huge G forces
| involved, especially so for large complex satellites.
|
| However, electronics have been subjected to such high G forces as
| far back as WWII but on a much smaller scale when the proximity
| fuze was introduced towards the end of the War (one of its first
| uses was at the Battle of the Bulge, Patton waxed lyrically about
| its high effectiveness):
| https://en.wikipedia.org/wiki/Proximity_fuze
|
| When I first heard about VT Fuzes years ago I didn't really
| believe it because it didn't use solid state devices, transistors
| etc. but rather a 'ruggedized' vacuum tube (this was several
| years before the transistor was invented in 1947). At the time I
| couldn't see how glass vacuum tubes could withstand [?]20,000Gs
| when fired out of a gun barrel but somehow they did.
|
| Therefore, I'd imagine that upgrading to solid state devices
| would allow an even higher scaling in the G department (i.e.:
| relative to the VT Fuze), so it seems highly possible (perhaps
| the SpinLaunch idea actually originated from VT type Fuzes, I'd
| not be surprised).
| ars wrote:
| I see this as being far more useful to send large quantities of
| fuel into orbit, and then use that fuel to accelerate to reach
| the outer planets.
|
| Electronics and such are pretty light, the regular rockets we
| have are fine for that. This is more for raw material, for
| example the structural components of a space station.
| vosper wrote:
| There's a good Curious Droid about proximity fuses. I had no
| idea how important they were to the allies.
|
| https://www.youtube.com/watch?v=N0SgC78YFPc
| hprotagonist wrote:
| it's very practical, if you want to hoik weapons systems.
|
| people, less so.
| causi wrote:
| Human bodies are a tiny fraction of the mass footprint of a
| space mission, and especially a deep space mission. Imagine
| the cost savings of spinlaunching the pieces of a vessel and
| supplies into orbit and then being able to launch an
| astronaut on a rocket the size of a telephone pole.
| dylan604 wrote:
| human bodies might only be a fraction of the mass footprint
| but they happen to be the most squishy part
| tnorthcutt wrote:
| Yes, that's their point - use regular rockets for the
| squishy humans, and spin launch the non-squishy bits at
| high-g.
| ceejayoz wrote:
| Or something like zero-notice "we need to get these
| antibiotics to the ISS" scenarios.
| jdmichal wrote:
| I've seen enough movies to know that the proper response
| to that scenario is to boost the ISS to escape velocity
| ASAP.
| duxup wrote:
| I don't know how viable this is but there is something both
| visceral, simple, and super futuristic about this whole idea.
|
| I don't know why but I'm excited about this idea.
| gameswithgo wrote:
| To temper your enthusiasm some:
|
| They cannot fling things to orbit, they can fling things very
| fast but a (smaller) rocket is still needed to finish getting
| to orbit.
|
| and G Forces are extreme so this is only suitable for payloads
| that don't mind extreme G forces.
| sschueller wrote:
| G force isn't even the issue. It's friction from the air as
| soon as the vehicle leaves the launch contraption.
| colechristensen wrote:
| Mach 6 or 7 at launch? No big deal to mitigate that.
|
| On reentry from orbit vehicles are going mach ~25.
| sidewndr46 wrote:
| Those kind of speeds are common at altitude, in the upper
| atmosphere.
|
| The drag and resulting heat production at sea level would
| not be as easy to deal with if you were zipping along at
| Mach 25 right after launch. Even supersonic aircraft
| don't run full speed (for a whole host of reasons) at sea
| level.
| [deleted]
| gameswithgo wrote:
| MongooseMan wrote:
| Sorry to put a dampener on things, but Thunderf00t has already
| done two debunking videos on SpinLaunch. He's rarely wrong.
|
| https://www.youtube.com/watch?v=9ziGI0i9VbE
|
| https://www.youtube.com/watch?v=ibSJ_yy96iE
| tekno45 wrote:
| Looks like one comfy armchair.
| LeifCarrotson wrote:
| Scott Manley also put out a video on Spinlaunch:
|
| https://www.youtube.com/watch?v=JAczd3mt3X0
|
| He...encourages caution. It's one thing to call a technology
| "debunked", another to say it's very difficult or that it has
| a low probability of success.
| dntrkv wrote:
| > He's rarely wrong
|
| About what? Most of his recent content is clickbait debunking
| videos about stupid ideas that no serious person has ever
| taken seriously.
|
| "Solar Roadways Debunked" Yeah no fucking shit.
| AlexDragusin wrote:
| > But the company says it'll be appropriate for smaller launch
| vehicles weighing up to about 440 lb (200 kg)
|
| In this particular configuration, the rotational kinetic energy
| for a 200kg load would be massive and the current materials would
| not be able to withstand it and another issue would be the
| release timing through the opening, as seen on the video the
| margin of error would be so narrow that is likely not possible
| with the current technology. I hope I am proven wrong in my
| armchair assessment though.
| throwawayboise wrote:
| I agree the entire thing sounds completely impractical and even
| if it can be made to work reliably, the number of suitable
| payloads would seem to be tiny. Maybe you could launch a 200kg
| billet of solid aluminum or titanium or other raw materials
| that could be used in space for manufacturing of components for
| a space station or Mars transport vehicle?
| na85 wrote:
| >In this particular configuration, the rotational kinetic
| energy for a 200kg load would be massive and the current
| materials would not be able to withstand it
|
| Got any numbers or facts to back this assertion up?
|
| I haven't investigated the mechanics behind spin launch, so I'm
| eager to see something concrete.
| ur-whale wrote:
| There is a lot of skepticism around spinlaunch:
|
| https://www.youtube.com/watch?v=9ziGI0i9VbE
|
| https://www.youtube.com/watch?v=ibSJ_yy96iE
| craz8 wrote:
| If NASA had plans for a moon base, and also had plans to send
| things back from there, this might become an interesting launch
| capability - no atmosphere and lower escape velocity provides
| more flexibility. Run it with stored solar power and it's self
| contained and needs no expendable supplies
| politician wrote:
| That's right. This is far more compact than the equivalent mass
| driver.
| aidenn0 wrote:
| I was so badly hoping they were building a launch loop. Still
| giant centrifuges are always fun.
| paparush wrote:
| Neal Stephenson nods in approval.
| andbberger wrote:
| the orbit infrastructure in seveneves was so much more elegant
| and viable than a giant centrifuge
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(page generated 2022-04-14 23:01 UTC)