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The problems with Starship make the Saturn V and STS programs even more impressive. However, I still don't get the rationale of building a rocket with such a large payload. The rocket equation will always force you to build an absolute monster compared to a series of smaller rockets. Even worse if you have to haul up a massive orbiter each time. No wonder that small/medium sized rockets (Soyuz, Atlas, Ariane, Falcon 9,...) have always been the most successful.





A larger rocket mitigates the effects of the rocket equation.

The wet (loaded with propellant) to dry (empty of propellant) mass ratio is determined via the rocket equation to be the exponential of delta V divided by exhaust velocity.

Certain parts of the rocket, such as the external tank structure, scale sub-cubically with the rocket's dimension, as do aerodynamic forces; whereas payload and propellant mass scale cubically.

Hence if the rocket is smaller than a critical threshold size, the requisite vehicle structures are too large relative to its propellant capacity to permit the required wet:dry mass ratio to achieve the delta V for orbit.

At exactly this size, the rocket can reach orbit with zero payload.

As the rocket increases in size beyond this threshold, it is able to carry a payload which is increasingly large relative to the rocket's total mass.


This is also why no hobby rockets get to orbit. Even a 1 gram payload to low earth orbit is beyond what a human-sized rocket can manage due to the way rockets don't scale downwards well.

Smallest orbital anything so far is 31ft(9.54m) long, 20in(54cm) wide, 2.9t/2.6t(2600kg?), does 9lbs(4kg) to random-ish LEO: https://en.wikipedia.org/wiki/SS-520

How does this compare to the cube-square law scaling effects applied to propeller- and wing-lifted vehicles like quadcopters/helicopters and RC aircraft/jumbo jets? Or even the squat shape of a housefly that zigs and zags through the air like an acrobat compared to the ponderous lift-off of a large goose?

I understand vaguely that those operate and scale based on the area (a square function of their length) of their lifting surfaces, and are pulled down by their mass (a cube function of their length).

A little Estes toy rocket lifts off the pad much more aggressively (in the blink of an eye!) than a full size rocket...


>A little Estes toy rocket lifts off the pad much more aggressively (in the blink of an eye!) than a full size rocket...

If you really want to, you can reach Mach 10 (~3300 m/s) with a 8 meter long 3500 kg missile in 5 seconds:

https://en.wikipedia.org/wiki/Sprint_(missile)

All of that in the lower atmosphere with the missile heat shield glowing white hot. :)


They are almost entirely unrelated. When trying to leave the gravity well of a planet, the atmosphere is only a dragging force acting to reduce your thrust. It might be proportional to the surface area of the vehicle, but likely not - I think it's only proportional to the surface area of the "nose" of the rocket. But what's certain is that it's strictly a force that hinders you - in a rocket, all of your thrust comes from the engines, you don't get any boost from the air.

However, even if you're taking off of a planet with no atmosphere, you still have a huge force to deal with - you need to maintain an acceleration to exit the gravity well of the planet, and you need to burn fuel for that. But you also have to carry the fuel you'll burn with you, so the more fuel you have, the more fuel you'll need - this is what the rocket equation codifies.


> But you also have to carry the fuel you'll burn with you, so the more fuel you have, the more fuel you'll need

Isn't this the entire point of using methane as fuel so that they can build a gas station once they get there so that return fuel is not required to be considered in this equation?


I'm not talking about fuel that you need to get back, we're still at the "leaving Earth" case. The point is that you need, say, 1000 tons of fuel to leave the Earth. Your rocket then will weigh [weight of empty rocket] + [weight of payload] + 1000 tons. And it is this mass that the engines will have to push while ascending. Of course, the fuel gets spent as you ascend - by the time you reach orbit, your rocket is now 1000 tons lighter.

ahh, I misread the part I quoted. doh!

The refueling idea is so that for example you don't need to carry the fuel needed to get to the moon or Mars all in one rocket. You just need to carry enough to get to the refueling orbit - which is much less.

The toys have to be aggressive. You have less than three feet worth of launch rail--by the time the rocket clears the rail it must be going fast enough that the fins make it stable. Meanwhile, it's light, overengineering the body to take a high g load is trivial.

An orbital class rocket--taking that kind of g load is going to break it (just look at the payload specs for the Falcon Heavy--its maximum permitted payload is well below it's performance to low orbit. You load it up to what the engines can do, it breaks. The only use case is when it's going farther than low orbit.) And an orbital class rocket has active steering rather than fins, it doesn't need to be booking it to be stable.


Most of the aggressiveness of a toy rocket is the smaller length. Orbital class rockets are literally the size of skyscrapers.

I'd posit that Mark Rober just used a hobby rocket to put that selfie satellite into orbit. Perhaps he's the first?

He used a commercial rideshare program.

> Our satellite launched on a SpaceX Falcon 9 rocket from Vandenberg Space Force Base in California (USA) on Jan 14, 2025. The rocket mission is a Transporter, and SAT GUS was dropped off in low-Earth orbit at about 375 miles above the surface of our pale blue dot.

https://space.crunchlabs.com/


Can you identify the rocket he used? Because from what I saw, I’m pretty sure it was a F9.

Added to that, Full-flow stage combustion engines are bigger, heavier, and more expensive, but are way more efficient. So a bigger rocket is the only option to get one of those onboard, and helps with taking more mass to orbit because they are more efficient than other options.

I don't believe there's any performance advantage for full-flow, which SpaceX alone is attempting. The only point is to lower the combustion temperature inside the turbines, at the expense of (much) higher flow rates through those turbines, in order to increase their lifespan.

(There's a large difference between staged combustion generally and gas-generator engines, which throw away performance by dumping fuel out of the turbine exhaust).


Since the temperature limit of available materials is the fundamental limitation (even after making custom high-temp alloys), this allows them to maximize mechanical power from the turbopumps, which raises performance.

We might imagine a conservative FFSC design which accepts very low temperatures in exchange for making it easy (low R&D cost) to reach high longevity. Raptor is not a conservative design, so it requires more R&D to achieve that longevity.

https://www.youtube.com/watch?v=twnZYPdFgbU


But you also have a limit on the other side: going extreme to make the point, we haven't managed to build a mile-tall building yet, and a rocket that size would be a nightmare to engineer (while perhaps technically possible -- you might have to scale up another 10x or 20x to make it physically impossible).

So there's some sort of curve, zero at both ends, between overall rocket size and the payload to orbit. The question is where Starship sits on that curve, and to your point it seems likely that it's looking good on that metric alone.

But then you have another curve that I think starts small and increases near-monotonically, which is the complexity/likelihood-to-fail factor to the size of the rocket. It's (relatively) easy to launch a toy rocket, (fairly) simple to build a missile-sized sub-orbital rocket, difficult to build a small-to-medium orbital rocket, and apparently very difficult to build a Saturn/N-1/Starship-sized rocket. More props to the crazy '60s team that pulled it off.


> So there's some sort of curve, zero at both ends, between overall rocket size and the payload to orbit.

This doesn't follow. Engineering complexity is not a limit on payload to orbit, it is a fundamentally different parameter. Yeah building a mile tall rocket would be hard, but it would get a shit ton of payload to orbit. There is no maximum beyond which making a bigger rocket starts to reduce your payload to orbit.

> But then you have another curve that I think starts small and increases near-monotonically, which is the complexity/likelihood-to-fail factor to the size of the rocket. It's (relatively) easy to launch a toy rocket, (fairly) simple to build a missile-sized sub-orbital rocket, difficult to build a small-to-medium orbital rocket, and apparently very difficult to build a Saturn/N-1/Starship-sized rocket.

Complexity does not increase with size, people just become more risk averse with size. Toy rockets fail all the time, just nobody really cares. No one would bet the lives of multiple people and hundreds of millions of dollars on a successful toy rocket launch. If complexity increases, it is with capability. If you want to land on the moon, you need something a bit more advanced than a hobby rocket. There is no reason to believe a floatilla of physically smaller rockets capable of achieving any given mission will be less complex in aggregate than a single physically larger rocket.


>> So there's some sort of curve, zero at both ends, between overall rocket size and the payload to orbit.

> This doesn't follow. Engineering complexity is not a limit on payload to orbit

At this point I'm merely talking about size (which I think is clear from the words I use. I don't think "building a mile tall rocket would be hard" adequately describes the difficulty when we haven't even built a mile tall building.

Sea Dragon[1] was only envisioned as 490 feet tall, and as near as I can tell even the Super Orion[2] would only have been 400-600 meters tall. And of course, neither of those was even close to implementation. Therefore I stand by my statement that a mile tall rocket is, for all practical purposes, impossible, and thus has a payload to orbit of zero. If you disagree then add a zero -- surely you agree we can't build a ten-mile-tall rocket?

As far as complexity, I'm not sure what to say. Toy rockets might fail all the time, but the point was complexity, and a toy rocket can be constructed from under a dozen parts. Even larger model rockets have at most a few dozen to a few hundred parts. The part count of the Falcon 9 has to number in the thousands, if not tens of thousands (9 merlin engines with at least several hundred parts each?).

To be clear, I agree with you that complexity increases with capability.

But also, to push back a bit, I don't think complexity aggregates the way you're saying it does. A box of hammers is not more complex than a nailgun, even if it has more parts in total.

   1. https://en.wikipedia.org/wiki/Sea_Dragon_(rocket)
   2. https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion)

> At this point I'm merely talking about size (which I think is clear from the words I use. I don't think "building a mile tall rocket would be hard" adequately describes the difficulty when we haven't even built a mile tall building.

I was assuming you were using a comical example to illustrate a "nightmare to engineer." The comparison to a building doesn't actually work at all. The practical limitation on how high we can build buildings is how fast we can make elevators. Just making something tall is not a problem.

> Sea Dragon[1] was only envisioned as 490 feet tall, and as near as I can tell even the Super Orion[2] would only have been 400-600 meters tall. And of course, neither of those was even close to implementation. Therefore I stand by my statement that a mile tall rocket is, for all practical purposes, impossible

First, the optimal design for a rocket is not to just keep making it taller, and second, size was not the obstacle to either of these projects not being built. That does not at all prove that it is impossible. What kind of world would we be living in we presumed anything that hadn't already been actively pursued was impossible?

> and thus has a payload to orbit of zero.

My point was that this does not equate to a payload of zero. Surely you wouldn't argue that the weight of this mile high rocket is zero, and therefore that there is some curve for the weight of rockets where making the rockets larger starts to make them lighter. Just as we can calculate the weight for something without actually building it, so too can we calculate the payload, and it can increase far beyond anything we can actually implement.

> If you disagree then add a zero -- surely you agree we can't build a ten-mile-tall rocket?

I agree it would be impractical, but not that it would be so non-physical that we couldn't calculate what its payload capacity would be were it to be built.

> Toy rockets might fail all the time, but the point was complexity, and a toy rocket can be constructed from under a dozen parts. Even larger model rockets have at most a few dozen to a few hundred parts. The part count of the Falcon 9 has to number in the thousands, if not tens of thousands (9 merlin engines with at least several hundred parts each?).

Falcon 9 is a liquid rocket designed to take people into space. That is the source of its part count. You could scale up a solid rocket motor to an arbitrarily large size while keeping the parts count exactly the same. It's probably not the optimal way to make a solid rocket of that size, and you'd be missing out on a lot of capabilities that are important for a real rocket, but if you just wanted a toy no more capable than what you buy in a hobby store it would be no more complicated. Conversely, try to make a fully functional falcon 9 complete with 9 working liquid rocket engines small enough to hoverslam on your desk and you have an immense engineering challenge on your hands.

> But also, to push back a bit, I don't think complexity aggregates the way you're saying it does. A box of hammers is not more complex than a nailgun, even if it has more parts in total.

I concur that part count is not the same as complexity, but that point is in my favor. Making something bigger is like adding hammers to a box of hammers. The quantity goes up, and at some point you're going to need to make some improvements to the box if you want to keep adding more hammers, but conceptually it is simple. Making something more capable, like a nail-gun, is much harder.


The failure modes of a mile-tall rocket would be spectacular. The sort of spectacular you want to be several hundred miles away from.

Even more impressive to me is the fact that Saturn V did in a single launch with 1969 technology, what we're now proposing to do with 10-15 Starship launches (each as large as a Saturn V) and an additional SLS launch for Orion return capsule. What's more, the US had orbital launch expereince of just 3 years (Explorer 1 in 1958) when the Apollo program began, and 8 years later they were on the moon. Perhaps web development is not the only thing that is susceptible to bloat.

Starship was designed from the very beginning to land humans on Mars and it is correctly sized for that. It's apples-and-oranges to compare its design to Apollo.

(edits:) It's clearly not ideal for a short lunar landing, considered in isolation. But: what else would you do? Whatever you build, it would land on the moon perhaps once, and never again. Would you, being in charge, design a one-off vehicle for one or two moon landings—spend that R&D budget, in that way? That's not cheaper than 15 Starship launches; it's considerably costlier. (But the Apollo engineers didn't need to worry about this; it's was their express remit to spend $200 billion on one-off designs that would never be used again).

And: I hope no one suggests the "just make a unique lunar Starship variant that's simply a bit smaller". There's no "simply" resizing things in engineering. Recall that the last time Starship's length was altered by 2 meters, new mechanical resonances appeared, and it blew up three times in a row. Any "one-off" change for lunar landings is a less-tested, less-understood machine you'd be putting human lives on.


> Whatever you build, it would land on the moon perhaps once, and never again.

But it would also never land on Mars, so it would be a waste to build it for that. Build it for what it will actually spend its life doing.

Not saying SpaceX won't go to Mars, but if/when they do it will likely be several rocket generations later and possibly with specialized rockets, with a significant portion of it being one-time-use as you ain't returning.


I completely forgot about this. Current aerodynamics and heat shielding are optimized for Earth reentry. They may have to significantly rethink the design for Mars. What they land on Mars will likely be very different from what we see today.

Even if it does go to Mars there are some major warts on the design. When you land you're 35-40 meters or so up in the air so there's a whole other elevator assembly needed just to get people out of the rocket to the ground.

We've been hoisting people and cargo up/down with pulleys and cables for thousands of years. This seems like the smallest obstacle Starship has to face.

We’ve been opening and closing doors for even longer and yet it has still posed a challenge for SpaceX when dealing with the payload door on Starship. Space makes even trivial things hard.

Sure. But they gotta fix the door, either way.

Winching stuff out of said open door seems like a much, much easier task.


The satellite door is completely different from what they'll need for MarsShip, that's even larger and has to function as an airlock. None of what they're trying to do now matters for the Mars door.

That's a lot of certainty for something that hasn't even been designed yet.

The outside door needn't be part of the airlock. It's certainly big enough to have an internal airlock leading to depressurized internal space.

The things that make a door that tests fine on Earth break in orbit are likely to be things that need fixing for a similar door on Mars. They won't be all the same challenges, but some will absolutely be shared.


On another planet as their only way on or off of the spacecraft is a whole different level of risk.

Everything's a risk nine months from Earth.

A hatch with a winch (or two!) seems likely to be one of the smaller ones.


What viable alternative design would not have this constraint?

A smaller purpose build lander that doesn't need the fuel capacity for the entire journey would be significantly shorter and could be wider too. That would get it significantly closer. Enough that a simple ladder would be viable so they aren't reliant on a winch/elevator.

So you're suggesting something similar to the Apollo LEM that will land, and carry enough fuel to return to orbit to dock with something that will contain enough fuel that will return to Earth?

Wouldn't that make the mission unfeasible because it requires ISRU of return fuel?


The Starship version of the Mars mission also requires ISRU. At least that's what was presented.

https://newspaceeconomy.ca/2022/05/27/how-will-spacex-make-r...


>Saturn V did in a single launch with 1969 technology,

for up to 0.8% US GDP per year. Today that would be $200B/year, pure spent. Where is Space X today is making, ie. it has a revenue, $15B/year.

>Perhaps web development is not the only thing that is susceptible to bloat.

similarly - web dev today can be done on $300 laptop by any schmuck. Even simple programming back then required a computer which cost a lot, and it was an almost academic activity.


This seems off. According to this: https://www.planetary.org/space-policy/cost-of-apollo (or in more detail: https://docs.google.com/spreadsheets/d/e/2PACX-1vTKMekJW9F8Z... )

Total lunar effort from 1960-1973, adjusted for 2024 USD: $326 billion

Launch vehicle costs (Saturn V): $113 billion

I think this is what should be compared against the total Starship program cost starting from 2020 until such time it completes 6 lunar landings (not counting SLS or other costs).

Or, for the year that Starship actually lands on the moon, compare against the Saturn V launch vehicle costs for 1969, inflation adjusted: $5.9 billion. See: https://docs.google.com/spreadsheets/d/e/2PACX-1vTKMekJW9F8Z...


Single Starship stack is <$100m so they are less than 1% in.

Sure, but spacex are building on the shoulders of what came before. Easy to save 200bn on research and development if someone else has already paid for it and shares the results for free.

This is true, but also a bit trivial to observe. Even the Primitive Technology channel, which usually starts with mud and clay, builds on knowledge of other people.

The value added is interesting. For example, both the Merlin and the Raptor family of engines. These are some fine engines, and they are remarkably cheap and reusable.


oh sure, no doubt - and the universe before that, etc. but here the baseline set by the comment i responded to was "whatever nasa spent 200b on".

I love this quote from Gwynne Shotwell when asked how they achieved that no government has: "The first is that we're kind of standing on the shoulders of giants."

Source: https://youtu.be/Dar8P3r7GYA?si=RHZ8lWFYKrd7qQhy&t=321


% GDP isn't an inflation adjustment.

0.8% US GDP in 1969 would be about 8B/yr today. Very different answer


US GDP 2024 is $29T. Thus 0.8% is $230B.

Expense scales with inflation, not GDP, which is the point.

> for up to 0.8% US GDP per year. Today that would be $200B/year, pure spent. Where is Space X today is making, ie. it has a revenue, $15B/year.

The likes of SpaceX are reporting costs in the range of $15B/year because NASA front loaded the cost of trailblazing launch technology half a century ago, with the technology available half a century ago.

Let's not fool ourselves into believing the likes of SpaceX are reinventing the wheel.

Also, those $15B are buying a fraction of the capabilities of SaturnV, and while SaturnV was proven effective and reliable 50 years ago, here we are discussing yet another "anomaly". Perhaps half these "anomalies" wouldn't exist if they weren't lean'ed into existence?


To be fair, they're also doing launches at a pace NASA could only have dreamed of back then. In 2024 SpaceX had 134 launches, we're far into the Space Shuttle program before Nasa had made that in total.

I wonder what "tons of payload to orbit" vs "dollars budget" would look like for Saturn era NASA vs Current SpaceX.

No doubt they're standing on the shoulders of giants, but let's not forget that they've helped transform the "go to space"-business.


> To be fair, they're also doing launches at a pace NASA could only have dreamed of back then.

That's like comparing how many containers Maersk moves today with how much sea cargo was moved back in the age of discovery.

Also, Saturn V worked and fulfilled it's mission, whereas Starship blows up.


Starship hasn't had a mission yet that I'm aware of. I love the Saturn V but I don't think this is a fair comparison. Just because your software didn't compile first try doesn't mean it's bad. Those two vehicles fundamentally have different approaches to development and that's fine.

> Starship hasn't had a mission yet that I'm aware of.

Then you will agree that comparing an unproven launcher which seems to be far far away from being able to fulfill a similar role is a very silly endeavour, let alone talk about it as a vast improvement which just so happens to blow up.


I don’t think it’s _that_ silly, there are plenty of cases where comparisons are useful. SpaceX’s development approach is radically different from traditional aerospace, but it’s clearly working for them. A bunch of Falcon 9s blew up too, and now it’s one of the most reliable and frequently used launch platforms in history. Why would you expect Starship to follow a completely different trajectory?

Apollo had plenty of failures during testing, including one that killed three astronauts.

> Saturn V worked

Its impressive how ignorant HN is about how many failures the S5 had during testing, falling for cold war propoganda at full speed


Testing on the ground and problems with what most people would call the payload (Apollo 1 & 13), sure.

But we're comparing to SpaceX launches. Plenty of Raptor engines have blown up on the ground too.

There were 13 Saturn V's launched and all of them basically performed their mission (Apollo 6 being a bit of an exception) with 0 rapid unplanned disassemblies...


I’m sure if the government gives SpaceX 200B a year to build a more reliable starship they can do it without blowing them up.

Actually, this version 2 of Starship was explicitly designed for lower the dry mass of the vehicle. It seems like SpaceX is exploring the lower limit on acceptable mass, and thus strength, of the Starship. This is a development program, after all.

This comparison doesn't make sense, the USD 200B/year was to invent the capabilities, do trailblazing work on something that needed to be proven even feasible as a concept, to do fundamental/foundational work, not to productionalise technology.

I'd expect SpaceX to do much more now than NASA in the 60s if granted USD 200B/year, considering they are already standing on the shoulders of giants.


Well sure, but they don’t have 200b a year. They’re doing more with (much) less.

> NASA front loaded the cost

Not even just NASA. SpaceX are building on technologies that originated from both sides of the iron curtain (and beyond)


Heck, fundamentally it's building on Iron Age technology, which is thousands of years old.

How far back is the "start" of history in this telling, and (more importantly) why?


It's not unreasonable to suggest that most of specifically rocket and spacefaring technology SpaceX uses now was introduced by someone else. Their main achievement is reusability and adjacent technical solutions.

Are you being deliberately obtuse?

The grandparent comment was pointing out that it cost NASA 200bn, and spaceX 15bn.

The parent comment pointed out that spaceX are actually saving money because they already got what nasa spent 200bn on.

My comment pointed out that they aren't just saving money by using NASAs tech, but tech from the Soviet Union as well - suggesting that their savings are far beyond just 200bn R&D


Not sure about parent poster, but to be fair NASA built on German WWII rocket/missile development, and Canadian know how after the collapse of Avro Canada.

How many billions was that?

This sort of "they're just building on" talk is weird to me, and not really relevant.

What SpaceX has accomplished is astonishing, and no belittling of their accomplishments should be tolerated.


Because in NASAs case it was "the stuff that came before" + 200b (or whatever the fantasy figure truly is).

Its unfair to say spaceX did what NASA did on a smaller budget (which is what the comment that kicked off this thread implied) because they DIDNT do what NASA did, and instead got "the stuff that came before" + "the stuff that NASA spent 200b on" + "the stuff from other sources that also cost billions" + the 15b that they actually spent to get where they are.

How can you disagree with that? You may think this discussion is silly - but its DIRECTLY as a response to someone implying that spaceX are achieving what NASA did with less money: https://news.ycombinator.com/item?id=44316227


> This sort of "they're just building on" talk is weird to me, and not really relevant.

Not really. You're not talking about technology. You're debating the economics behind it. You're seeing naive fanboys praising SpaceX's costs for the likes of Starship by comparing them to the cost of the SaturnV project, arriving at the simplistic conclusion that Starship is cheaper. This is like comparing your cheap Android phone as being far cheaper than a 1950s UNIVAC. And when the silliness of this specious reasoning is called out, your reaction is to downplay it as "not really relevant"?


Read the comment I'm replying to. Now read mine.

That said, you're upset that I said comparing costs isn't relevant? Isn't that the case you're making right now, that the costs cannot be compared, therefore aren't relevant in this discussion?

My tact on non-relevance, is that saying "it was built on another program's tech!" is not relevant, because everything meets that criterion. For example, as I said, the Saturn was built on decades of German research, including war time research during WWII, into rockets. Saturn's US development costs were a fraction of overall rocket research done by the Germans!

So if upthread is going to argue "but it's all built on the Saturn, and free knowledge!", then the same argument can be carried further back, thus negating this argument. Why?

Because it makes the Saturn cost trillions.


> costs cannot be compared

Thats the whole point for this entire thread. Pointing out that you CANT compare the costs of spaceX with NASA because spaceX is building on NASAs (and others) achievements.

Maybe you need to go back and reread this entire thread rather than suggesting others do so.


And I'm negating that, because the "built on" argument makes no sense for the reasons specified.

Simultaneously, I am also using my same logic to argue that you cannot compare costs due to my reasoning.

I agreeing with the point (you can't compare costs) while disagreeing as to why.


Well there are many reasons as to why - i just gave a single example. I don't see why you don't think prior knowledge has any value, but I guess you are entitled to your opinion.

I never even hinted that prior knowledge has no value. Not once.

Instead, I said it is an impossible thing to compare, for everything is built upon another. In fact, everything is built upon a myriad of other things.

Really, both the Heavy and the Saturn cost about the same. That's because they both depend upon the entire sum of human knowledge and research, to be built.

A billion trillion trillion trillion in today's dollars of knowledge gained and experience honed, over millions of years. So what if one cost a billion trillion trillion trillion, and another cost a billion trillion trillion trillion + a few billion more. The difference is meaningless, and not even worth considering.

And then there's the whole "how much is new" argument, and there's new knowledge aplenty thanks to SpaceX.

I really don't get these arguments. People seem to really love to denigrate the effort, the excellent results. It's beyond bizarre. And worse, mock because test flights, expected to possibly go sideways, do?

So weird.

"Hi, I'm going to see if this will work. It'll probably explode. But if it does, I'll learn something"

<boom>

hahaha it exploded you suck

I don't get it.


So it sounds like we should be comparing Starship and Heavy to SLS?

What a ridiculous point of view.Do you know how many anamolies nasa had on the way to make the Saturn 5? Orders of magnitudes more blow ups than Space x has ever had

Not to mention the comparable Soviet N1 rocket never launching successfully before being canceled.

Whenever my Volkswagen car software glitches I can't help but to observe it was done by a 6000 people strong development team vs 600 in Apollo programme within similar timeframe. The latter had vastly more primitive hardware, tools and younger programming culture available too.

The Apollo programme had some serious human capital. The best minds aren't working on infotainment. (EDIT: not car infotainment, anyway...)

And some serious financial capital working on enabling technologies. NASA funding peaked at 4.4% of US GDP. Even considering that this was 1960s GDP and they weren't standing on the shoulders of 100 years of automobile development or decades of previous launches, NASA got (and needed) a lot more resources than car manufacturers or newspace companies

Funding as percent of GDP is a meaningless metric. You need to adjust for inflation, but funding as a percent of GDP was some weird argument made to try to explain why modern NASA has become relatively ineffectual, but it has no meaningful connection to reality.

The Apollo Program cost a total of $183 billion, inflation adjusted, over 12 years. That's about $15 billion a year. NASA's budget has been for the past 40 years has been $20-$30 billion a year. Even the 'burst funding' wasn't particularly extreme relative to what they now regularly receive. The highest their budget ever was was in 1966 in $57 billion (inflation adjusted) dollars.

To visualize the absurdity of this argument imagine somebody claiming that Uganda funding a space program for $5 billion is receiving some serious financial capital, because that happens to be 10% of their GDP. $5 billion is $5 billion, regardless of your GDP. Ok technically there's PPP calculations, but that doesn't apply to the discussion here.


I mean, I was responding to a thread implying that the Apollo programme had access to fewer resources than Volkswagen firmware updates...

Obviously percentage of GDP isn't an ideal multiplier for reasons you've mentioned, but then inflation indexed mainly to mass produced common consumer goods tends to significantly underestimate the increase in cost over time of running complex operations involving the world's smartest and most on-demand minds and an almost unfathomably large number of subcontractors. Either way, NASA's overall budget is half that of the 1960s in regular inflation adjusted dollars, and whilst its current research and satellite/ISS maintenance maybe aren't as exciting as the first lunar landing, they're not obviously dramatically lower cost (the %GDP argument gets brought up nearly as often to suggest the Apollo programme wasn't worth it...)

Sat in a lecture theatre with NASA's last chief economist using both metrics earlier this week. Although those slides were looking at cumulative funds spent on Robert Goddard's programme, which was about the size of a largish Series A using the inflation metric or Series B using the GDP adjustment. Whether that's value for money or not depends on whether you're considering being the father of modern rocketry more impressive than sending a handful of moderately complex 16U Cubesats or rideshares or note that the actual rockets were no more sophisticated than some student projects, I guess...


NASA's modern budget isn't eaten up by satellite and ISS maintenance, it's eaten up by pork/corruption like the SLS. The SLS was already largely obsoleted by the Falcon Heavy 7 years ago. And Starship will make it look like a 13inch black and white CRT (with a million dollar price tag) in the era of cheap 80" bendy flat screens. Artemis is a similar story. Artemis simply isn't going to work. The entire project is filled with unrealistic handwaving.

Yet NASA continues to cheerlead for these things. I briefly thought NASA might right their heading under Bridenstine but then at some point he suddenly just did a hard 180. It seems every man has his price. He eventually just turned into another Boeing cheerleader (and his new found rubber stampage is a big part of why that Boeing monstrosity left astronauts stranded on the ISS) and went straight from out of office to a high level advisory gig for some MIC company which is almost certainly just a laundered paycheck.


Several lives, national pride, and a new human frontier was riding on Apollo, but not VWs infotainment.

It's not just infotainment though. We had all instruments blanked out on a motorway. Granted not as terrifying as with Apollo 13 but we had 3 people onboard too.

If something were to happen to Apollo, the blast radius would be limited to those 3 people. If something happens to your car with 3 people onboard while travelling down the motorway, the blast radius could affect other cars with their people onboard. This would make the failure even more spectacular having unsuspecting civilians affected vs 3 highly trained volunteers for mission. All this to say that I think we are way underplaying "it's just a car" type of thoughts here

ouch

Car software is, perhaps counterintuitively, doing a lot more than the Apollo software did. Just think about the computers available at the time and how much memory they didn't have.

Apollo project software was controlling the stages of Saturn V flight vehicle, orbital and lander modules, and ground systems. So no, it was not doing less than a family SUV Javacsript blob; certainly not 10x less. And most of the things it did were mission critical.

All isolated systems or sensors that simply notify humans or providing them with basic calculations. The MP3 and entertainment systems on modern cars are orders of magnitude more complex. Again, you don't have to take my word for it, just look at the memory available at the time.

Computers in Apollo programme controlled most of the function with minimal human involvement in the loop. The dynamic systems were orders of magnitude more complex than what you find in a modern vehicle.

Also I can assure you no-one at Cariad had to write an MP3 decoder. And speaking of sensor control, my car (on its 4th year now) still fails to unfold the mirrors once in a while.

We also have huge, orders of magnitude advances in tooling and process since mid-1960s. For starters you don't have to weave your program into magnetic core fabric by hand.


That's okay, as it is more than made up for by the lack of memory by the car's operators


You know the saying about OSHA rules "they're written in blood"?

That's what happens with most domains. At first people don't know the dangers and can go fast and loose: surgery, radioactive material, planes, cars, trains, rockets. Then people start losing their lives or part of their bodies to "easily preventable accidents". So some rules are enacted. Decade after decade, accident after accident, more rules, more red tape: things cost more, take more time. But you get a lot less victims.

So yeah, with a good budget and in a less strict country you could get something to the moon in no time. And potentially many people' parts all over your launchpads too.


> At first people don't know the dangers and can go fast and loose: surgery, radioactive material, planes, cars, trains, rockets

Gas pipework: https://www.youtube.com/watch?v=pR486zloao0


Not to mention that before natural gas people used to light and heat their homes with coal gas/town gas, which was basically carbon monoxide. Yes, that highly poisonous thing that binds better to hemoglobin than oxygen molecules. So you could get poisoned and then still explode.

You are comparing "sending a small crew for a few days on the Moon ASAP for propaganda purposes" with "setting up a permanent outpost on the Moon".

Do you know the McMurdo permanent Antarctica base is costing us far more than the dogs, sleds, and tents of Admundsen and Shackleton? Incredible, isn't it?


This is an inane comparison.

Starship is “the program to build a permanent base in the moon”. It’s not even the only vehicle involved in the moon program. It’s a rocket designed to take astronauts from moon orbit to the moon’s surface. The astronauts will actually fly to the moon in SLS.

So far it’s proved incapable of being launched, attaining orbit, and returning to earth as designed. That’s without a payload.

It has no life support system built and is literally years behind schedule.

Rather than making progress it is being redesigned on the fly to mitigate fundamental problems with its capability which Musk laughs off as “moving fast and breaking things”.

The problem is we aren’t moving fast at all.

The rocket is a disaster. Saturn V was better by an order of magnitude and likely cheaper if you consider how much fundamental work went into creating it which is now easy to buy off the shelf.

Comparing the programs while ignoring the fact that hobbiest regularly reach the Karman line is deceitful.

Starship is doing this on easy mode and it’s failing.


> Starship is doing this on easy mode and it’s failing.

But this 'easy mode' is still so incredibly hard that nobody else will even attempt it.

I'd love to see some serious competition emerge in the reusable rocket space, but SpaceX is far, far ahead with Falcon 9 being an incredible success, even if the Starship project may be headed for failure. Nobody reports on 100+ successful Falcon 9 launches/landings in a year, those are now mundane. But a small number of Starship failures - test flights of an experimental vehicle - become big news, mostly because they involve spectacular explosions.

It seems that Starship may be too big to 'fail fast', mostly because of the visual spectacle of those failures.


The 'easy mode' is incredibly hard at least partly in terms of nobody else having the capability to finance it (with the possible exception of two superpowers and Jeff Bezos)

But yeah, I tend to agree that whether it ultimately succeeds or not, blowing Starship up is a "fail fast" strategy because they have the money (and the reputational capital from successful Falcon 9 launches) to learn from their mistakes that way, and not many others do. Much as the waterfall approach of big space projects gets derided, there's a reason entities that can't take the reputational hit of visibly blowing stuff up on a regular basis do it that way...


> The astronauts will actually fly to the moon in SLS

The program that was paused pending new NASA director, and has burned more money than SpaceX without a single (usable) launch?

I’m making things up out of memory here, but suffice to say SLS does not have my confidence.


IMO calling it "easy mode" really misses the mark. If you ever get the chance to hear directly from the engineers working on Starship, I think you’d come away with a deeper appreciation for the scale and complexity of what they’re building. The solutions they work on go far beyond "just" launching a rocket.

I know right, I think people just spitting on bullshit

I have much respect to this guys that works in here that really pushing the innovation beyond the limit

reusable rocket is the future if you want permanent present in space, there is no way you throw rocket for only 1 launch


> Saturn V was better by an order of magnitude and likely cheaper if you consider how much fundamental work went into creating it which is now easy to buy off the shelf.

One year of Saturn V development cost the same as the entire Starship program so far. One launch cost 20-30x more than the projected cost of a Starship launch.

It is also said that it’s simply impossible to rebuild a Saturn rocket. Not only you can’t “buy components off the shelf” because they simply don’t exist anymore, even if you had all the component blueprints (which we don’t, they were lost to time), the manufacturing know-how is long gone.

Starship was developed from scratch. SpaceX developed their own engines, their flight control surfaces are novel, the rocket structure and materials are novel, the entire approach is different. Yes, our modern electronics industry makes it “easier” but this is like saying Porsche is playing in easy mode because of the Ford Model T.


It's hard to compare costs when one rocket works and the other doesn't. If Starship never works then the cost is a bit irrelevant.

I propose my own imaginary rocket. It costs $0 but it doesn't exist. Totally beats the Saturn V on cost!


[flagged]


have no idea why the replacement plan isn't launching orion on falcon 9 heavy and rendezvousing with orion on dragon

Nice one. Now do SLS.

I'm going to guess you don't actually know anything about SLS or rockets at all.

How are the astronauts supposed to get on lunar soil on SLS?


> You are comparing "sending a small crew for a few days on the Moon ASAP for propaganda purposes" with "setting up a permanent outpost on the Moon".

No, OP is comparing a launcher that worked reliably (it's in the history books) with a launcher which never performed a mission and is reporting "anomalies".


Many Saturn V stages blew up on test stands as well (its also in the history books) and some flight were very much on the edge of success. It was also not trying to make the whole system reusable and economicaly sustainable (just check when the last Saturn V flight was - if it was sustainable it would be still flying, right ?).

Launched reliably... 12 times.

> Launched reliably... 12 times.

Was it required to launch more?

How many moon missions did Starship fulfilled? It seems 50 years ago SaturnV launched 12 times more than Starship.


Reliable statistics require a minimum of 30 samples.

> what we're now proposing to do with 10-15 Starship launches

That's complete nonsense. 10-15 Starship launches would land a lander that can carry like 100tons of payload orbit.

Saturn V landed 15000kg on the moon, but most of that isn't payload.

But of course with Saturn V you are throwing away a rocket that cost 1 billion $ or more per launch.

You are comparing 'thing lands on moon' to 'things lands on moon' without any nuance.

But you are right Apollo was insane in how fast it was done.


I don't think GP meant 10-15 Starships missions needed to carry the same payload, but 10-15 test launches necessary before it's ready for real. I think the Saturn V had only two test flights before it took people around the moon.

No, GP is referring to the refuelling missions that will be required to put Starship on the moon and bring it back.

Which as the person you're replying to is point out isn't really a fair comparison because Starship and Saturn V deliver vastly different amounts of mass to and from the moon despite the mission being only to ferry some people there for a few days.

If Starship ends up flying to the moon it effectively enables the landing of a lunar base that could be occupied for years at a time with sufficient resupply of food and the right equipment for extraction of water/oxygen from the moon.

The Saturn V as amazing as it was could never have brought that much equipment to the moon in a cost effective manner.


refuelling makes a lot of sense in the long terms

also military (space force)


Significant parts of the Saturn V (including the S-IVB 3rd stage, and the instrument unit which controlled the entire stack) were previously flight tested in Saturn IB launches.

> That's complete nonsense. 10-15 Starship launches would land a lander that can carry like 100tons of payload orbit.

The burning question that I have now is whether a Starship explosion during lunar testing will be visible from Earth. I sure hope they would do it during a new moon too for maximum effect.


SpaceX is currently spending around $100m per launch for 'things that don't get into orbit', never mind land on the moon.

So yes, I suppose that is more inefficient, in a way.


First, you don't have any idea what those numbers actually are.

Second, SpaceX has consistently shown lower development cost then anybody else. Starship is expensive its likely cheaper then New Glenn.

Remember, Ariane 6, a marginal upgrade over Ariane 5 with only a new upper stage engine cost 6 billion $.

And SpaceX is already at much higher launch rates and manufacturing rates for thing like engines. SpaceX is investing into mass production already.


Remind me exactly how the Saturn V rocket returned to its launch pad?

> STS programs

The shuttle was a deathtrap. It had inadequate abort modes and a launch process that practically guaranteed minor (until it wasn't) damage to the heat shield during launch.

Classic example of https://danluu.com/wat/ --- the normalization of deviance.

STS crews were lucky that only two of the things got violenly disassembled.


> It had inadequate abort modes

Does Starship have launch abort boosters? Seems infeasible with the amount of fuel and mass on it since it also serves as a second stage, but maybe they solved that somehow?


Starship doesn't currently have launch abort modes

Nor does it have any crew / passenger cargo.

DearMoon was supposed to launch 2022, passenger space service between LA and Ridhya by 2028 (announced in 2018 and they said it was on track for 2028 still several years later). They said it would be around the price of business class air travel and be in full commercial operation by then. That might have been after they started adding "aspirationally" to most Musk company statements following some lawsuits.

Sure, the Saturn V and STS were much less safe than smaller rockets. Still, they blew up an awful lot less than other rockets of their size like N1 or Starship.

Many Saturns blew up during testing. Starship is still in testing.

Your arguments are strange, a mirage concocted to fit a narrative of denigration and darkness. You mock with zeal, yet have no point to the mocking.

Always with the mocking, you cause an ache which cannot be balmed. Cease, I pray you. Stop these machinations, this mad canter.

Falcon was built the same way. It blew up many times too, explosions aplenty. Now it is the most successful lift on the planet.


Would love to read about Saturn V explosions during testing. Have a link?

The Saturn V second stage (S-II) has at least two examples listed as destroyed during testing:

https://en.wikipedia.org/wiki/S-II

"First all-up S-II stage, assembled between 1963 and 1965. Completed several engine tests at the Mississippi Test Facility (now the Stennis Space Center). Destroyed by accidental LH2 tank overpressurization during pressure testing May 28, 1966[7][6]"

and

"Destroyed in test stand September 29, 1965"

Also described here: http://heroicrelics.org/ussrc/s-ii/index.html

"The S-II program was beset with problems and delays. NASA had planned on North American making an S-II stage, S-II-D, for dynamic testing but the order for that stage was cancelled in early 1965 in favor of using the structural static test stage, S-II-S, as a combined static/dynamic test stage; that stage was renamed to S-II-S/D. Unfortunately, the S-II-S/D stage was destroyed during testing, leaving S-II-F to take on the added role of dynamic testing and being redesignated as S-II-F/D."

I though all of the Saturn V stages were destroyed during testing at least once but it looks like I remembered it wrong. :)


I recall reading the engines blew up in testing, the rockets on the pad, on and on. And why wouldnt it?

No one has ever built a plane, or even a car without breakage during testing. The very idea is absurd. There's a whole profession called "test pilot".

I don't know why anyone would suggest otherwise.

I'm sure there are links aplenty, but the absurd suggestion here would be building a rocket and having zero incidents of failure. That beyond weird. That's what needs a "do you have a link" question.


> I recall reading the engines blew up in testing, the rockets on the pad, on and on. And why wouldnt it?

You're recalling wrong, or you were reading nonsense. Lots of engines were destroyed in testing (particularly before computer modelling, this was basically how rocket engines were _developed_), but no, no Saturn V ever exploded on the pad. Prior to this incident, the most-impressive on-pad boom was one of the N1s.

No fully assembled Saturn V ever failed, though a few of them had near-misses.


Well we're discussing testing only here, so are you sure none explpded on a test a pad?

It's a weird debarc point to discuss non testing craft vs testing. And "fully assembled", when spacex is flying non-final builds on purpose, using a different test methodology.


> Well we're discussing testing only here, so are you sure none explpded on a test a pad?

Yes! I am sure! That did not happen!

Early development of Saturn V rocket engines involved destructive testing, but a whole rocket would not have been involved at that point.

Here's some later ground testing of final engines: https://www.youtube.com/watch?v=-rP6k18DVdg


Engines during testing, sure, but did a Saturn V ever sit fully fueled on a pad, and explode?

A fully fueled starship stack hasn't exploded either. Yesterday's anomaly was a failure of just the upper stage.

No Saturn V ever blew up on the pad.

Upvote for phrasing.

> Still, they blew up an awful lot less than other rockets of their size like N1 or Starship.

I think the only reasonable comparison would be after cost equivalency. The Starship has a long way to go, to catch up.


Cost equivalency ignores the R&D and decades of scientific progress and advancements in tooling capability. The prices of materials have shifted, but designing and manufacturing a precise propulsion system with modern CAD and simulation tools is a lot cheaper than the hand work hundreds of people used to be doing to verify much simpler engine designs. Precision machining and tools to inspect metal fatigue and imperfections have also come a long way.

Of course commercial rockets are always going to be as shoddy as they can get away with rather than as good as possible, but if it still takes SpaceX or Boeing as much money to build a rocket as it did back in the Saturn V days, they're doing something wrong.


If you use that as an argument any comparison becomes meaningless by default.

Also, both Saturn V and the Space Shuttle were dual-purpose programs - they had military goals on top of the scientific ones.

Well the military purpose was why the Shuttle was so crappy. The original design was smaller and meant to sit on top of its rocket. This would have probably prevented loss of crew in both of the instances where shuttle failed.

Eventually Starship will also be bid for military programs.

And Saturn V never had a military mission, neither had Shuttle.


Shuttle regularly launched spy sats and was designed to grab an enemy one in a single orbit mission. Also Soviets believed it would nuke Moscow by sudden plane change via its wings & build their own version as a result.

That sounds military enough for me.


The bombing of the Soviet Union was to happen via polar launch. The wings were there not for plane change, rather for cross range landing after the single orbit polar mission.

Interesting - I was never sure about the exact mechanism m, just that the orbital speed & lift provided by wings were part of it. :)

The Space Shuttle never had a combat mission, in the sense that it was never used to drop bombs via polar orbit over the Soviet Union. But of course it had tens of military missions, the Shuttle launched many department of defense satellites.


> However, I still don't get the rationale of building a rocket with such a large payload

Operations cost. They are sublinear on payload/size. At least this is what Space X/Musk seem to go for.


https://en.wikipedia.org/wiki/Big_dumb_booster

There's also many advantages to being able to lift something large/heavy in one go, rather than smaller payloads that need to be unfolded (like JWST) or assembled in space, which can drastically increase the development costs.


Falcon 9 is by no means small or even medium. In the history of rockets its quite a large and powerful rocket. And so is Ariane 5. Not sure what you are referencing with Ariane, I guess Ariane 1-4 were small.

So far in history, we didn't have enough to launch. If the volume we launch increases then a larger rocket flying often is helpful.

We are at the peak of what a rocket the size of Falcon 9 can do. If you want full re-usability, the size helps you out quite a bit.

And hauling the 'orbiter' into 'orbit' is only wasteful if you can't reuse it. I would argue what's actually wasteful is throwing the second stage in the ocean, even when it costs minimum 10million $, and likely more.


I suggest you read up on the rocket equation again. There is a massive difference between payload mass fraction and payload. The latter scales linearly with respect to the total mass.

That's the problem. Building a heavier rocket is much harder than building a lighter one (see explosion above). So why not send a few lighter ones instead of a heavy one? This is what the launch market has concluded for a long time.

This is a long but great video from Destin that goes over this in detail: https://www.youtube.com/watch?v=OoJsPvmFixU&pp=0gcJCdgAo7VqN...

Destin’s arguments make sense if we want to redo Apollo. They break down if we’re trying to make repeated missions into deep space more economical.

> Building a heavier rocket is much harder ...

Disagree. The overall Starship system's problems are obviously in Starship, not in the Super Heavy booster. The latter is far heavier. But it only has to do 2 things well - sub-orbital launch, and sub-orbital precision return. And the launch tower's chopsticks give it a lot of help with the latter.

Vs. the Starship has to do far more things - all of them mission-critical - while being ruthlessly optimized for weight.


>So why not send a few lighter ones instead of a heavy one? This is what the launch market has concluded for a long time.

   I want to do Apollo again.[0]

[0] https://www.youtube.com/watch?v=A4J9uvhJQM0

Let’s assume starship works out and they come up with a nifty wide-opening payload door solution, one of the advantages will be payload volume as well as mass - the JWST’s main mirror would have fit inside without being folded (although the heat shield would not have).


What Saturn V and the Shuttle were trying to do pales in comparison to what the design goals of Starship are. If you were trying to repeat what those vehicles were doing you would've designed the launch vehicle significantly different.

Compared to Starship, Falcon 9 may look like a medium rocket, but it is actually quite big, and Falcon Heavy is bona fide a heavy launcher, not just a hype-name.

Note that Saturn several stages on the test stand like this.



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