Stoke Space Technologies: General Company and Development Updates and Discussions

[deltaV]

I don't think economics of distributed launch make sense for Nova. Once it needs 2-3 launches,  launch price will be same as 1 larger LV eg Neutron or F9 that can do same mission with single launch for lower risk.

Refuelling from depot is different but still adds extra mission risk from refuelling.

A few years ago Stoke was thinking about costs of $250 per kg (https://x.com/jenakuns/status/1457849962692165635). That's less per kg than F9, which is ~$3k per kg, even if there's 10x Nova cost growth from inflation and reality. So if larger vehicles outcompete Nova it will probably be fully reusable vehicles like Starship, not partially reusable vehicles like Neutron and F9.

[ZachF]

I get that the architecture has full re-use baked into it, but when I see discussions about orbital re-fueling being the solution, I get very skeptical. Launching at a high cadence is hard and not many people do it. RP operations are hard and not many people do it. For one, let's see SpaceX prove it out first. But I think it's going to be quite a while where someone like Stoke Space is capable of launching 6 flights in rapid succession, achieving zero boil-off and long-duration flight, RPO to refuel, and then landing the whole thing. I'm not sure they would even be capable of pulling off such a thing in 10 years time.

Tugs and third stages seem like a much more practical and feasible solution to high-energy needs.

The difference in ambition between the companies themselves and people here is quite stark. Stoke isn't even attempting to land the Nova upper stage on their first flight (likely 2027).

I think that's fair. But I think it's worth noting that Stoke has quite a lot more margin for error here than SpaceX does.

6 Nova flights to fully refuel is certainly better than Starship, at least. Which makes it a little bit easier for me to feel optimistic about the refuelling operations for Nova going well.

But also, because Nova is so small, Stoke always has the option of refueling their stage in a single Falcon 9 or New Glenn 7x2 launch, if they must. Probably New Glenn (hydrogen infrastructure, using GS2 as a tanker is already a planned capability, etc.). That's definitely still worse than just putting a third stage on New Glenn. But for Stoke, paying Blue Origin to launch their propellant is a fine fallback option, if they find themselves having trouble putting complete refueling campaign together. Unlike Starship, where that just has to work.

It's ~10 for Starship V4 to fully fuel itself, but a fully fueled Starship V4 also seems to have more DV (~6750 vs ~5250 for Stoke).

They could also contract Blue or SX to launch a depot for them, which would ease logistics.

My guess is if Nova is successful and proves their concept, they will make a "Supernova" with ~20t to LEO capacity, which would probably be a >1300t rocket if they can improve upon the mass ratio to orbit in spite of likely square-cube issues with the heatshield design on a larger rocket. 24 Zenith engines uprated from 150 to 250 bar could power the first stage. This size would also have the benefit of being able to fully refill a Nova in one go.

[deltaV]

My guess is if Nova is successful and proves their concept, they will make a "Supernova" with ~20t to LEO capacity

I agree that if Nova is successful they'll almost certainly build a bigger rocket. They may build the bigger rocket themselves or they may cooperate with or merge with another company that already has a larger partially reusable vehicle. My hunch is that somewhere in the 30-80t to LEO range would better complement Nova than your ~20t guess.

[TrevorMonty]

My guess is if Nova is successful and proves their concept, they will make a "Supernova" with ~20t to LEO capacity

I agree that if Nova is successful they'll almost certainly build a bigger rocket. They may build the bigger rocket themselves or they may cooperate with or merge with another company that already has a larger partially reusable vehicle. My hunch is that somewhere in the 30-80t to LEO range would better complement Nova than your ~20t guess.

There is quite bit of room for block upgrades with Nova while still using existing booster diameter. 4.2m. F9 is 3.7m but does use denser RP1. So 20mt (expendable) is realistic without coughing up $Bs for heavy RLV with new pads and infrastructure.

Where are all payloads going come from to justify heavy RLV, especially as they will be competing directly with NG and SS. Both of which should be fully reuseable well before Stoke can field this new LV.

[edzieba]

Have Stoke ever even claimed they intent to refill their upper stage in orbit?

In Tim Dodd's recent site visit, Andy Lapsa mentioned that the first mission was targeting not jus a high energy orbit, but Earth-escape (presumably burn-to-completion and see how much delta-V they can generate), explicitly to demonstrate high-energy orbit capability with a lower-payload stage. Over-and-above even Stage 2 entry testing. That all points to in-orbit refuelling to not be a consideration for their architecture.

[jongoff]

Have Stoke ever even claimed they intent to refill their upper stage in orbit?

In Tim Dodd's recent site visit, Andy Lapsa mentioned that the first mission was targeting not jus a high energy orbit, but Earth-escape (presumably burn-to-completion and see how much delta-V they can generate), explicitly to demonstrate high-energy orbit capability with a lower-payload stage. Over-and-above even Stage 2 entry testing. That all points to in-orbit refuelling to not be a consideration for their architecture.

I'm not sure if they've publicly spoken about in-space refueling, but I'm sure it's on their roadmap.

~Jon

[TrevorMonty]

Have Stoke ever even claimed they intent to refill their upper stage in orbit?

In Tim Dodd's recent site visit, Andy Lapsa mentioned that the first mission was targeting not jus a high energy orbit, but Earth-escape (presumably burn-to-completion and see how much delta-V they can generate), explicitly to demonstrate high-energy orbit capability with a lower-payload stage. Over-and-above even Stage 2 entry testing. That all points to in-orbit refuelling to not be a consideration for their architecture.

I'm not sure if they've publicly spoken about in-space refueling, but I'm sure it's on their roadmap.

~Jon

Distributed launch with single refuelling can make massive difference to BLEO performance. ULA paper
add x2 payload or greater gain on missions going further than GSO. Between GTO and GSO its <x2.

This made sense when ULA were only game in town and were launching deep space missions.
Now that there are lot more LVs with higher performance its less risky and probably cheaper to do single launch on more powerful LV.

Unless there is depot in orbit selling cheap fuel don't see case for it with Nova in near term.

[adrianwyard]

They have certainly gone as far as creating graphics showing refueling in orbit - attached.

The economics of a fully re-usable vehicle have never been played out in reality before, so saying anything with certainty is a challenge. IF their first vehicles are rapidly re-usable with minimum (inexpensive) refurbishment, then refueling opens up lots of options; their promo videos show the upper stage on the Moon! And why not, from strictly a delta-V POV. Additionally, gaining flight reliability data, and expanding the test envelope (landing cross-winds?) is a reason to fly often, regardless of whether there's fuel on board for another vehicle.

However, it really is early days for just about everything with this project, and many ways for it to fall flat. It may be that by the time they've added sufficient robustness to make it rapidly re-usable the payload shrinks to irrelevance. And the performance of the novel upper stage/heatshield needs to be proven in flight. Excitement guaranteed, though.

[jongoff]

Have Stoke ever even claimed they intent to refill their upper stage in orbit?

In Tim Dodd's recent site visit, Andy Lapsa mentioned that the first mission was targeting not jus a high energy orbit, but Earth-escape (presumably burn-to-completion and see how much delta-V they can generate), explicitly to demonstrate high-energy orbit capability with a lower-payload stage. Over-and-above even Stage 2 entry testing. That all points to in-orbit refuelling to not be a consideration for their architecture.

I'm not sure if they've publicly spoken about in-space refueling, but I'm sure it's on their roadmap.

~Jon

Distributed launch with single refuelling can make massive difference to BLEO performance. ULA paper
add x2 payload or greater gain on missions going further than GSO. Between GTO and GSO its <x2.

This made sense when ULA were only game in town and were launching deep space missions.
Now that there are lot more LVs with higher performance its less risky and probably cheaper to do single launch on more powerful LV.

Unless there is depot in orbit selling cheap fuel don't see case for it with Nova in near term.

I'm not sure I agree with your assessment. If Stoke can get upper stage reuse sorted out, there's a decent chance that in-space refueled Nova missions to high energy orbits could be cheaper than with more traditional alternatives that have expendable upper stages. Depends a bit on the overall architecture and the chosen orbit, but given the potentially much lower marginal $/kg cost of a fully-reusable vehicle vs a partially reusable vehicle, I wouldn't dismiss the concept out of hand.

~Jon

[jongoff]

They have certainly gone as far as creating graphics showing refueling in orbit - attached.

The economics of a fully re-usable vehicle have never been played out in reality before, so saying anything with certainty is a challenge. IF their first vehicles are rapidly re-usable with minimum (inexpensive) refurbishment, then refueling opens up lots of options; their promo videos show the upper stage on the Moon! And why not, from strictly a delta-V POV. Additionally, gaining flight reliability data, and expanding the test envelope (landing cross-winds?) is a reason to fly often, regardless of whether there's fuel on board for another vehicle.

However, it really is early days for just about everything with this project, and many ways for it to fall flat. It may be that by the time they've added sufficient robustness to make it rapidly re-usable the payload shrinks to irrelevance. And the performance of the novel upper stage/heatshield needs to be proven in flight. Excitement guaranteed, though.

I'm glad you found that public reference. I've definitely talked with them about their interest in in-space refueling of the upper stages, but wasn't sure if that info was out in the public domain (hence being really careful with how I worded my responses).

Agreed that we're still in the early days of trying to get full RLVs operational and learning what they really unlock. Theoretically, full RLVs plus refueling (especially with a depot) seem really enabling and potentially much more affordable than alternative solutions, but the devil in this case is definitely in the details. I think it's one of those where in hindsight it's going to be obvious, and our kids are going to be asking what took us so long to figure this stuff out. But proving things out in foresight is always harder than showing how obvious it was in hindsight.

~Jon

[deltaV]

Have Stoke ever even claimed they intent to refill their upper stage in orbit?

In Tim Dodd's recent site visit, Andy Lapsa mentioned that the first mission was targeting not jus a high energy orbit, but Earth-escape (presumably burn-to-completion and see how much delta-V they can generate), explicitly to demonstrate high-energy orbit capability with a lower-payload stage. Over-and-above even Stage 2 entry testing. That all points to in-orbit refuelling to not be a consideration for their architecture.

Stoke's short-term plan for high-energy missions, e.g. the performance numbers on their website I posted a few weeks ago, seems to be no refueling and expend one or both stages. But in the long term Stoke presumably has a plan to do high-energy missions with full reuse, and that probably requires either propellant transfer or a third stage. Propellant transfer would probably be much cheaper than developing a third reusable stage so presumably they'd try propellant transfer first.

[Hug]

Stoke's short-term plan for high-energy missions, e.g. the performance numbers on their website I posted a few weeks ago, seems to be no refueling and expend one or both stages. But in the long term Stoke presumably has a plan to do high-energy missions with full reuse, and that probably requires either propellant transfer or a third stage. Propellant transfer would probably be much cheaper than developing a third reusable stage so presumably they'd try propellant transfer first.

Worth noting that they do have a patent for a reusable third stage.
https://patents.google.com/patent/WO2025188725A1

Also Y Combinator video release

Chapters:
00:00 — Intro
01:16 — Stoke Space’s mission: Rapid reusability
02:18 — Why Second Stage capsules fail reentry
03:34 — Stoke Space’s stage 2 solution
05:30 — Reusability-First Design Philosophy
07:25 — Early Engine Development & Test Strategy
10:48 — Vertical Integration & Manufacturing
11:21 — Iteration Speed as a Competitive Advantage
12:29 — Software as Core Infrastructure
14:00 — Path to Orbit & Launch Operations
15:04 — How This Could Change The World

Facility is designed to build about seven vehicles per year...

What rapid reusability allows you to do is to scale the flight frequency without having to scale your factories and your test facilities and all the infrastructure that comes with it.

So a 168,000-square-foot headquarters is able to put out 7 vehicles a year, which is theoretically a lot of capability. There is the interesting question now of whether a reusable launch vehicle is cheaper to develop to a certain cadence given the technical risk buy down and the reduction in infrastructure CAPEX is non-trivial.

[TrevorMonty]

Is middle picture the test flight payload?
9

[laszlo]

Is middle picture the test flight payload?
9

Yes, the Large Language Animal Model Assistant

[StraumliBlight]

0069-EX-ST-2026 [Jan 9]

Start Date: 07/01/2026
End Date: 12/31/2026

LV Stage 1 - Suborbital
LV Stage 2 - Orbital

Experiment Description is restricted.

[catdlr]

https://twitter.com/stoke_space/status/2014698780247945468

Stoke Space
@stoke_space
BOOM! 💥 There it is, our flight termination system (FTS) in one of many tests to validate its performance and overall reliability for our Nova rocket program. (🔊 Sound on)
 
The FTS is a component of Nova's Autonomous Flight Safety System (AFSS) that continuously monitors the vehicle’s trajectory against pre-defined safety limits and autonomously commands termination if needed.

[zubenelgenubi]

Cross-post:

SFN Eastern Range ready for same day fueling of Space Launch System, Vulcan rockets, January 23, Will Robinson-Smith

<snip>
Rare launches for the Artemis program aside, the Eastern Range is preparing for another big year in orbital launches. Teams are readying for a future where by 2035, according to some external studies, the Cape may juggle 350 or more launches per year from a host of launch providers.
<snip>
Col. Joyce Bulson, the deputy commander of the USSF’s Space Systems Command (SSC) Space Launch Delta 45:
“It’s very possible that you could have a launch by either of them by the end of the calendar year. Stoke is a provider on Lane 1 of [the National Security Space Launch contract]. Relativity is not, but we’re excited to see both of those successes.”

[deltaV]

I made a poll for when Stoke Space's Nova will first launch: https://forum.nasaspaceflight.com/index.php?topic=64251.

[catdlr]

https://twitter.com/stoke_space/status/2016511418212725212

Stoke Space
@stoke_space
·
This is substantial infrastructure right here!" Another great moment from the latest @Erdayastronaut  visit to Stoke with
@AndyLapsa, when Tim gets to experience the Zenith engine test stand at our Moses Lake facility. Check it out:

[321]

Any plans to make manned spacecraft or lunar lander out of Nova S2?