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Just now, YNM said:

They were putting a furnace on zero-G flights. We also haven't seen much for like plant and animal growth + breeding. Plus other 'mundane' things, usually to do with crystals or with thermodynamics.

For actual microgravity experiments, humans and not only unnecessary,  but counterproductive. Real industrial microgravity stuff needs free-flier platforms without the vibration, etc associated with humans.

1 minute ago, derega16 said:

Or is it possible to use SM as a 3rd stage? So, neutron will put the capsule into suborbital and the capsule do the rest

It's certainly stubby enough that stage 2 looks like it could stretch some, or add a S3.

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I guess my point was that Rocketlab may not be intending to serve the ISS at all. Perhaps they envision other stations to launch to. Or maybe this mention of human-rated capability is just to drum up interest.

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Just now, tater said:

Real industrial microgravity stuff needs free-flier platforms without the vibration, etc associated with humans.

Yeah, though I suppose you could do that if you have a station nearby. Human operators is useful because the form factor and operation sequence is much less strict than if it's entirely robotic, that's all. Same thing with down here.

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I suppose humans can board, set up an experiment, then LEAVE, and come back to pick it up later. That might allow experiments that require less sophistication—no need to put the whole thing inside an entire spacecraft that can also reenter. Or they can even stop the experiment, and go take data on orbit (it might not survive reentry forces).

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Just now, mikegarrison said:

I guess my point was that Rocketlab may not be intending to serve the ISS at all.

Even if they do it'd fall more on 'tourism' than actual scientists. This is why I was wondering if any slot is even left among the major space programs, the only thing I can come up is either the ISS commercialization effort or the rich oil nations, or both.

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1 minute ago, mikegarrison said:

I guess my point was that Rocketlab may not be intending to serve the ISS at all. Perhaps they envision other stations to launch to. Or maybe this mention of human-rated capability is just to drum up interest.

Well, the most likely other station right now might well be the Axiom one, since they are actively working on it, even if it starts out for several years stuck to ISS.

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2 minutes ago, tater said:

I suppose humans can board, set up an experiment, then LEAVE, and come back to pick it up later.

You'd need a spacecraft that have the payload capability then to launch and to re-enter the experiments (and the humans).

Edited by YNM
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38 minutes ago, derega16 said:

Or is it possible to use SM as a 3rd stage? So, neutron will put the capsule into suborbital and the capsule do the rest

Well, if they design their own capsule then they already have multiple options for the service module engine and RCS thrusters -- Rutherford, Curies, or HyperCurie.

But I suspect you'd want to get a stable orbit on the first two stages alone. 

6 hours ago, RealKerbal3x said:

From https://www.rocketlabusa.com/rockets/neutron/

BJ3Irus.png

This is getting me really excited :D

Very crude render, but nbd.

With no aero control surfaces, I wonder if they will try to build on the Electron heritage and use supersonic chutes to ensure good pointing and help reduce the necessary landing propellant. You have to have pretty precise targeting for a platform landing, though.

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Cool for people farther north than FL, since they plan to launch the thing from Wallops.

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Im realy interested in their stock, they want to go public. Would be nice to be able to invest into real spaceflight, not that porkgrabbing of ULA. Sadly SpaceX isnt free to buy for ordinary folks (im quite sure they will be worth billions in 1-2 decades), so Rocketlab it is...

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31 minutes ago, Elthy said:

Im realy interested in their stock, they want to go public. Would be nice to be able to invest into real spaceflight, not that porkgrabbing of ULA. Sadly SpaceX isnt free to buy for ordinary folks (im quite sure they will be worth billions in 1-2 decades), so Rocketlab it is...

The problem with being public is that their goal is then shareholder value on whatever time horizon current investors aim for.

 

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1 hour ago, Elthy said:
Im realy interested in their stock, they want to go public. Would be nice to be able to invest into real spaceflight, not that porkgrabbing of ULA. Sadly SpaceX isnt free to buy for ordinary folks (im quite sure they will be worth billions in 1-2 decades), so Rocketlab it is...

Same here.

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Yeah, SpaceX’s “Make humans multiplanetary” goal is not something that’s going to show great returns on investment any time soon. Rocket Lab, on the other hand, seems much more willing to cater to the market rather than what’s necessary for The Mission, which makes them a better fit for going public. Even if I have my doubts about this particular announcement, I still think I wanna buy a few RKLB shares when they start selling, just to have them. 

Edited by RyanRising
Fixed ticket.
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4 hours ago, tater said:

Yeah, Soyuz (spacecraft) is small.

Small for LEO is fine, it's a taxi.

It has almost the same total usable volume as Crew Dragon (and more volume per person) and life support for 3 weeks. It’s used as LEO taxi, but it’s not small (huge compared to Gemini, Mercury, Vostok or Voskhod). If RL made something like Soyuz, maybe even with a single pressurised module, it could easily do long duration flights. As for destinations, well, it can orbit with tourists on its own at first, later bring them to some kind of space hotel. Maybe launch Space Marines from Space Force to some military installations in LEO. 

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2 minutes ago, sh1pman said:

It has almost the same total usable volume as Crew Dragon (and more volume per person) and life support for 3 weeks. It’s used as LEO taxi, but it’s not small (huge compared to Gemini, Mercury, Vostok or Voskhod). If RL made something like Soyuz, maybe even with a single pressurised module, it could easily do long duration flights. As for destinations, well, it can orbit with tourists on its own at first, later bring them to some kind of space hotel. Maybe launch Space Marines from Space Force to some military installations in LEO. 

I consider Dragon too small for anything long duration, honestly. Soyuz has more usable volume than the Apollo CM—but being crammed in that for many days with at least a couple other people is less than ideal. Even Soyuz is the size of a small bathroom in my house. Probably smaller than any bathroom in my house by some margin, actually. So 3 people literally living in a bathroom (and it is indeed also the toilet). I understand for the sort of human space travel we have had up to this point, Soyuz is not small comparatively—but aside from Shuttle, they have ALL been small. I'd almost say my personal definition of "not small" would be that it have a dedicated toilet room.

 

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Well, assuming they want tourism, how many orbits do they need? One or two would be enough, right? So, this would be the duration of a short car trip. They might not need docking equipment, either. How light could they make this capsule?

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1 hour ago, SOXBLOX said:

Well, assuming they want tourism, how many orbits do they need? One or two would be enough, right? So, this would be the duration of a short car trip. They might not need docking equipment, either. How light could they make this capsule?

They have 8 tons. They can actually do a perfectly acceptable LEO spacecraft for all manner of work, as was said, that's more mass than Soyuz, and empty space for crew is... empty.

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Well, clearly someone with experience developing a partially-reusable medium launch vehicle thinks this was a good move: 


Maybe I was a bit too eager to think this was a move made of desperation, a sort of “Hail Mary.” Maybe it’s going to be just fine, and everything will work out. Hope so.

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1 hour ago, RyanRising said:

Maybe I was a bit too eager to think this was a move made of desperation, a sort of “Hail Mary.” Maybe it’s going to be just fine, and everything will work out. Hope so.

It's a bit of both, I think.

Doesn't matter, competition is good. There's the other cash cow, as well. Rocket Lab can launch USAF/NASA payloads, and this signals that in a few years there will likely be 3 launch providers all with reusable stages, and all competing on cost.

Northrop Grumman and ULA should be concerned.

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7 hours ago, tater said:

Northrop Grumman and ULA should be concerned.

Mainly the former, I think. Although if the 8 tonnes-class LEO missions (and corresponding GTO mass of ~2 tonnes) remains growing stronger as it had from the 80s then ULA should be concerned as I can only see Vulcan doing something like Ariane 5 dual-payload missions most of the time, which means increased wait times. It's really interesting looking at space payloads because they're dictated by the rockets too.

Edited by YNM
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i think that rocketlab has been very clever with the Neutron design; making it very stubby means that they can somewhat easily:

-stretch it as they improve their engines/ put a 3rd stage

- enlarge the fairing, i know it is not like KSP that you can do whatever you want, but falcon 9 has demostrated that a high finess ratio rocket can reliably carry a bigger paload fairing than it's body ( and even more so the new falcon heavy fairing). If the falcon 9 at 3.75 meters can carry a 5 meters fairing, probably the neutron 4.5 metrs width  can accomodate a 6 meter fairing without too many issues.

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So let's talk about Neutron. Here's that comparison I know you all want....

They put the fairing diameter at 4.5 meters and their images show the fairing as being slightly smaller than the body of the rocket, but the rocket skin is probably a touch thicker than the fairing anyway so I'll just say 4.5 meters all the way down. 

It definitely looks like they are going with stainless steel construction aping Starship, which is fascinating.

By pixel count, I'm getting the following height measurements:

  • Stage 1 (total): 28.2 m
  • Stage 1 (tankage): 25 m
  • Interstage: 3.5 m
  • Stage 2 (total): 7.3 m
  • Stage 2 (tankage): 5.8 m

I'm also getting a first-stage engine bell diameter of 1.4 m, though I don't really put much stock in that because it's the easiest thing to render.

Assuming common bulkheads and nearly-flat spherical caps, that gives us an estimated volume of 397 cubic meters on the first stage and 92 cubic meters on the second stage. I doubt they'll be doing densified propellant, so with a bulk density of roughly 1.02 tonnes per cubic meter, that's a propellant load of 405 tonnes on the first stage and 94 tonnes on the second stage.

Given stainless steel construction at a much smaller size than Starship, I'm going to ballpark a propellant mass fraction of about 92%, giving us a first stage dry mass of roughly 32 tonnes and a second stage dry mass of roughly 7.5 tonnes. With an 8-tonne payload, this would give it a GLOW of 546.5 tonnes, almost exactly the same as Falcon 9.

In the render, the vehicle diameter is 323% the engine bell diameter. You can fit seven engines into a circle at 300% but there's no room for gimbal. Looking at that render closely, I'm actually thinking this is a four-engine first stage, perhaps with a central Rutherford engine for the landing burn like the LinkSpace design. This would mean the engines would need to have a SL thrust of around 1800 kN each.

There's no way engines that size could fit in that tiny interstage with a properly-sized expansion nozzle, so I suspect they will do a pair of vacuum Rutherfords for the upper stage.

 

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23 hours ago, sh1pman said:

It has almost the same total usable volume as Crew Dragon (and more volume per person) and life support for 3 weeks. It’s used as LEO taxi, but it’s not small (huge compared to Gemini, Mercury, Vostok or Voskhod). If RL made something like Soyuz, maybe even with a single pressurised module, it could easily do long duration flights. As for destinations, well, it can orbit with tourists on its own at first, later bring them to some kind of space hotel. Maybe launch Space Marines from Space Force to some military installations in LEO. 

Soyuz is lightweight because its has the orbital module, the launch and reentry module is tiny. 
Reuse has an cost penalty. 

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