Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

SpinLaunch is building a centrifuge to launch satellites into orbit

wired.com

Post reply on HN
Print view View original

131–140 of 152 posts

Re: SpinLaunch is building a centrifuge to launch satellites into orbit

#131

Post by mhandley »

graderjs wrote: post #116
mhandley wrote: post #112

Earlier quoted context omitted.

Exactly - the energy of the released counterweight will inevitably produce an explosion as it's stopped pretty quickly by something. My question was how big an explosion. The answer is pretty big, but this probably isn't their biggest problem.

Liquid back stop? Ballistic jello?

500MJ is enough energy to flash-boil 200Kg of water, so that might work. Would be a sizeable steam explosion, as the 330 or so cubic meters of instantaneously created steam tries to go somewhere, and an interesting pressure wave in the water tank.

Re: SpinLaunch is building a centrifuge to launch satellites into orbit

#132

Post by joezydeco »

clnhlzmn wrote: post #105
marsokod wrote: post #100

Earlier quoted context omitted.

And the mechanical and thermal shocks it gets when it passes from the vacuum chamber to the atmosphere. IMHO the centrifuge part is the easiest of their challenges.

That's what seems to me to be the biggest challenge too. Going from vacuum to 1 atm at 4000 mph has got to be quite a shock. Might as well just smash the thing into a wall.

And what is the inrush airspeed when you have that large of a vacuum?

Zero to Mach 5 or 6 just seems like an instantaneous disassembly manuever, both for the craft and the centrifuge itself. Did they find a way to suppress a sonic boom at the exit point?

Re: SpinLaunch is building a centrifuge to launch satellites into orbit

#133

Post by czottmann »

brohee wrote: post #113
absolutelyrad wrote: post #78

Earlier quoted context omitted.

Thanks, this is what I was looking for. I didn't want to dismiss them fast, but it did sound like the founders don't know what they're up to. Maybe they figured out some advanced materials science we don't know about, but that seems unlikely from this article. > Over the next few years, the team ran hundreds of high-speed tests. Most of them were to study and improve the system, but some were to mollify skeptical inv…

How many G is a drop on concrete?

1, I guess.

Re: SpinLaunch is building a centrifuge to launch satellites into orbit

#134

Post by hollerith »

Havoc wrote: post #97
Cthulhu_ wrote: post #58

Earlier quoted context omitted.

Not sure how serious you are with the radioactive waste thing but I'll do the HN thing and bite (nerdsnipe!), because that's not going to work. You can't launch things into the sun, you need to decelerate objects. The earth travels at 30 km / s (70K MPH) around the sun, so you need to decelerate about that much the other way. And orbiting radioactive waste is just asking for trouble. The total amount of radioactive w…

>The earth travels at 30 km / s (70K MPH) around the sun, so you need to decelerate about that much the other way. Surely you’d just need enough to end up in a decaying orbit? Then it’ll eventually reach the sun

Low-earth orbits decay because of friction between the spacecraft and the Earth's upper atmosphere. What do you imagine would guarantee the decay of a solar orbit before a perturbation (by, e.g., the gravity of the Earth's moon or a comet) sends the orbiting object into a collision course with Earth?

Re: SpinLaunch is building a centrifuge to launch satellites into orbit

#136

Post by [deleted] »

bob1029 wrote: post #85

10000g peak forces are a bit of a mess for space travel. Perhaps instead of directly spinning the object up to speed and "letting go", you could build up all of the energy into a heavy rotating mass which then imparts it into the spacecraft over a slightly longer timeframe via some simple mechanical clutch and cable arrangement. You would still have very strong g-forces, but you could control the impulse curve over t…

[deleted]

Re: SpinLaunch is building a centrifuge to launch satellites into orbit

#137

Post by JoeAltmaier »

absolutelyrad wrote: post #90
londons_explore wrote: post #88

Earlier quoted context omitted.

Assume the screen and top glass of an iPhone are 40 grams. 10000g's will make the effective mass of them 400kg. Could an iPhone survive 400kg sitting on top of it? It's definitely within the realm of possibility...

The force is acting on internal parts too. I don't think the silicon microchip inside can survive those forces. There is just too much that could go wrong here. I would be positively shocked if this thing works. I'd have to rethink a lot of things I hold an opinion on.

Maybe they cushioned it? Embedded in a gel or some such. That definitely helps.

Re: SpinLaunch is building a centrifuge to launch satellites into orbit

#138

Post by TaylorAlexander »

_Microft wrote: post #66
TaylorAlexander wrote: post #56

Earlier quoted context omitted.

Starship development continues apace. They’re planning to launch the latest starship vehicle to 50km altitude next week and then perform their difficult landing maneuver 15km from the launch site. I believe the sweating skin idea has been dropped. See this one hour video for a detailed breakdown of the current state of the design: https://youtu.be/-8p2JDTd13k

It's being launched up to 15km, that's pretty close to 50000 feet, so you might have mixed up the units.

Oooh I see. The tweet I read said 15km/50k ft altitude and I misread that as 15km translation and 50km altitude. Thanks for the correction!
Post reply on HN