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There's something I don't understand about space travel. We made it to the moon in 1969, on the first computer to use ICs[1]. Since then we've seen monumental

There's something I don't understand about space travel. We made it to the moon in 1969, on the first computer to use ICs[1]. Since then we've seen monumental advances in computer science, material science, manufacturing, rocketry, and just about any other component of space flight. Why 50 years later is it still such a relatively difficult task to launch a rocket into space? Why is it still so expensive and failure prone, when we were able to launch so many vessels with substantially less capable technology? It seems like space travel simply has not scaled with the rest of our technology, but I imagine I'm missing something. Perhaps the ratio of human life to risk tolerance has increased, such that we effectively spend more time and resources designing away failures and refuse to launch with the same level of risk that was acceptable decades ago? 1. https://en.wikipedia.org/wiki/Apollo_Guidance_Computer#Design https://en.wikipedia.org/wiki/Apollo_Guidance_Computer#Desig...

robbiep 9y ago
Literally what you are witnessing now is the scaling of that. Rockets are expensive - there hasn’t been the opportunity for rapid iteration such as during the rise of automobiles or planes, so there have been less opportunities for the sorts of experiments such as what SpaceX, blue origin, armadillo before it, and the electron are doing.
adventured 9y ago
Apollo cost ~$120-$150 billion in today's dollar. Falcon Heavy cost $500m-$1b to get right. Given some time, Musk could probably make it so a trip to the Moon costs $300 million, maybe less. We've (they've) accomplished an extraordinary cost improvement. It's still such a monumental task, because the laws of physics have not changed. Building a huge rocket, putting people in it, and firing it at the Moon, is not the hard part per se (not killing them in the process, and bringing them back safely, is). We could have done that all over again at any time if we desired to spend the money. The next level of difficulty, is turning it into a truly routine task, and building something on the Moon. That's a dramatic leap up from only exploring the surface of the Moon. We've avoided doing that, not because we can't, but because it's a cost benefit equation, and the benefit has not been considered worth doing at the cost, even as the cost gradually declined. Now that cost benefit equation has improved dramatically enough to favor it being worth doing. Simply put, as a society we're not willing to spend $500 billion or $1 trillion to build a Moon base. But we might be willing to spend $50 or $100 billion over time to do it. We're not willing to spend $10 or $20 billion for a trip to the Moon, but we are probably willing to spend $300 million or even a billion.
- simonh 9y ago
  That’s not quite a fair comparison. The $500m to $1bn was just for the heavy variant, it doesn’t include the cost of developing the F9 itself. Musk has previously estimated the cost of just developing the landing capability by itself at about $1bn. But still, yes it’s a lot less than Saturn V.
- vermontdevil 9y ago
  Don’t forget Merlin design is based on an engine developed during the Apollo program. The lunar descent engine. There has to be some savings in that when Musk and Mueller developed the current engine. But that’s fine. I’m good with our tax money from prior programs helping future endeavors. https://en.wikipedia.org/wiki/Descent_Propulsion_System https://en.wikipedia.org/wiki/Descent_Propulsion_System
rocqua 9y ago
It has to do with the rocket equation [1]. Getting into orbit requires a lot of 'delta-V'. Part of this is gravity (needing to move up the gravity well) but more important are speed (you need to go really fast to stay in orbit) and aerodynamic drag when moving through the atmosphere. There have been no real improvements to the exhaust velocity of rocket engines (at least none that work to get into orbit). As such, to get more delta-V we need to do that with the dry-full mass ratio. This means we really care about the dry mass of our rockets. This in turn pushes engineering to the limits. The sweet-spot between weight-savings and reliability is skewed more towards the weight-savings side. Beyond the rocket equation, there is the issue of little iteration being possible. Launching rockets is expensive, so it is not done often. Moreover, failing to launch a rocket is even more expensive. This makes it take a long time to figure out what works by real life testing. Combine the weight skimming with the massive forces and complexity of a rocket, and you get some problems that can essentially be found only by real life tests. As real life tests are few and far between, it just takes longer to learn the lessons needed. This is something space-X has gotten quite good at, by always iterating on their design and doing tests. This is helped by the relative cheapness of launches for them. Cheap launches means you can try more per launch. [1] https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation
- vlasev 9y ago
  > Part of this is gravity (needing to move up the gravity well) but more important are speed (you need to go really fast to stay in orbit) Technically speaking, the speed requirement is due to gravity as well.
InclinedPlane 9y ago
Look at some of the other responses here, they give a hint. The core problem is lack of reuse, which means you expend one hugely expensive aerospace vehicle per flight, massively increasing per flight costs. Importantly, the optimizations for expendable flight actually drive you away from optimizing for reusability. Expendable vehicles tend to have fewer engines on the first stage, cheaper first stages, and expensive, advanced upper stages. The Falcon 9 intentionally places the majority of hardware costs in the first stage, uses a cluster of engines, and is thus more suitable for reusability (it's easier because landings are easier, it's more worthwhile because most of the hardware cost of a launch is in the booster). On top of that you have the fact that throughout the world launch vehicle development has traditionally been dominated by only a few major programs that were run by governments. That substantially restricted rocket development due to the bureaucracy and the different needs and goals of governments vs. launch vehicle customers at large (governments are risk averse, have big pockets, etc.) Additionally, launch vehicle development was heavily restricted as a practical matter during the Cold War. Launch vehicles serve as dual use ICBMs, and the first launchers were indeed repurposed ICBMs. Meaning launch vehicle development had very serious national defense and geopolitical implications, so you didn't see a bunch of "space launch startups" during the Cold War the way you see today (SpaceX, Blue Origin, Rocket Labs, etc.) Then there's the brain drain on aerospace technical talent during the Cold War as well. If you had the education or the skills to work on this stuff then most likely you were pulled into some military or government aerospace project since that's where the money (and the national interest) was. Engineers in the 1960s and '70s could have built reusable rockets if that had been the goal, but it never really was. Even with the Space Shuttle the priority was covering the political bases first (being able to serve the needs of everyone who was supporting the program and keeping it funded) and practical cost savings a distant second.
burnte 9y ago
The political and public will isn't there to spend hundreds of billions of dollars to do it. Luckily with SapceX and Blue Horizon making things so much cheaper, we can get that will back.
Nomentatus 9y ago
True, we haven't launched THAT many rockets or kinds of rockets: but according to Musk, oligopolies and rent-seeking has been most of the problem keeping us stuck; with everything from sourcing Aluminum to finding a better way than just milling a huge chunk of it, and on and on. No real competition, so little real research or change, and providing that was his motivation to throw his hat into the ring.
marktangotango 9y ago
I'll throw out another answer no has mentioned yet; those cats back in the 60's were good, damned good. They did an exceptional job with what they had. Recall the SR-71 is from that era as well.

robbiep 9y ago

Literally what you are witnessing now is the scaling of that. Rockets are expensive - there hasn’t been the opportunity for rapid iteration such as during the rise of automobiles or planes, so there have been less opportunities for the sorts of experiments such as what SpaceX, blue origin, armadillo before it, and the electron are doing.

adventured 9y ago

Apollo cost ~$120-$150 billion in today's dollar. Falcon Heavy cost $500m-$1b to get right. Given some time, Musk could probably make it so a trip to the Moon costs $300 million, maybe less. We've (they've) accomplished an extraordinary cost improvement. It's still such a monumental task, because the laws of physics have not changed. Building a huge rocket, putting people in it, and firing it at the Moon, is not the hard part per se (not killing them in the process, and bringing them back safely, is). We could have done that all over again at any time if we desired to spend the money. The next level of difficulty, is turning it into a truly routine task, and building something on the Moon. That's a dramatic leap up from only exploring the surface of the Moon. We've avoided doing that, not because we can't, but because it's a cost benefit equation, and the benefit has not been considered worth doing at the cost, even as the cost gradually declined. Now that cost benefit equation has improved dramatically enough to favor it being worth doing. Simply put, as a society we're not willing to spend $500 billion or $1 trillion to build a Moon base. But we might be willing to spend $50 or $100 billion over time to do it. We're not willing to spend $10 or $20 billion for a trip to the Moon, but we are probably willing to spend $300 million or even a billion.

simonh 9y ago
That’s not quite a fair comparison. The $500m to $1bn was just for the heavy variant, it doesn’t include the cost of developing the F9 itself. Musk has previously estimated the cost of just developing the landing capability by itself at about $1bn. But still, yes it’s a lot less than Saturn V.
vermontdevil 9y ago
Don’t forget Merlin design is based on an engine developed during the Apollo program. The lunar descent engine. There has to be some savings in that when Musk and Mueller developed the current engine. But that’s fine. I’m good with our tax money from prior programs helping future endeavors. https://en.wikipedia.org/wiki/Descent_Propulsion_System https://en.wikipedia.org/wiki/Descent_Propulsion_System

rocqua 9y ago

It has to do with the rocket equation [1]. Getting into orbit requires a lot of 'delta-V'. Part of this is gravity (needing to move up the gravity well) but more important are speed (you need to go really fast to stay in orbit) and aerodynamic drag when moving through the atmosphere. There have been no real improvements to the exhaust velocity of rocket engines (at least none that work to get into orbit). As such, to get more delta-V we need to do that with the dry-full mass ratio. This means we really care about the dry mass of our rockets. This in turn pushes engineering to the limits. The sweet-spot between weight-savings and reliability is skewed more towards the weight-savings side. Beyond the rocket equation, there is the issue of little iteration being possible. Launching rockets is expensive, so it is not done often. Moreover, failing to launch a rocket is even more expensive. This makes it take a long time to figure out what works by real life testing. Combine the weight skimming with the massive forces and complexity of a rocket, and you get some problems that can essentially be found only by real life tests. As real life tests are few and far between, it just takes longer to learn the lessons needed. This is something space-X has gotten quite good at, by always iterating on their design and doing tests. This is helped by the relative cheapness of launches for them. Cheap launches means you can try more per launch. [1] https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation

vlasev 9y ago
> Part of this is gravity (needing to move up the gravity well) but more important are speed (you need to go really fast to stay in orbit) Technically speaking, the speed requirement is due to gravity as well.

InclinedPlane 9y ago

Look at some of the other responses here, they give a hint. The core problem is lack of reuse, which means you expend one hugely expensive aerospace vehicle per flight, massively increasing per flight costs. Importantly, the optimizations for expendable flight actually drive you away from optimizing for reusability. Expendable vehicles tend to have fewer engines on the first stage, cheaper first stages, and expensive, advanced upper stages. The Falcon 9 intentionally places the majority of hardware costs in the first stage, uses a cluster of engines, and is thus more suitable for reusability (it's easier because landings are easier, it's more worthwhile because most of the hardware cost of a launch is in the booster). On top of that you have the fact that throughout the world launch vehicle development has traditionally been dominated by only a few major programs that were run by governments. That substantially restricted rocket development due to the bureaucracy and the different needs and goals of governments vs. launch vehicle customers at large (governments are risk averse, have big pockets, etc.) Additionally, launch vehicle development was heavily restricted as a practical matter during the Cold War. Launch vehicles serve as dual use ICBMs, and the first launchers were indeed repurposed ICBMs. Meaning launch vehicle development had very serious national defense and geopolitical implications, so you didn't see a bunch of "space launch startups" during the Cold War the way you see today (SpaceX, Blue Origin, Rocket Labs, etc.) Then there's the brain drain on aerospace technical talent during the Cold War as well. If you had the education or the skills to work on this stuff then most likely you were pulled into some military or government aerospace project since that's where the money (and the national interest) was. Engineers in the 1960s and '70s could have built reusable rockets if that had been the goal, but it never really was. Even with the Space Shuttle the priority was covering the political bases first (being able to serve the needs of everyone who was supporting the program and keeping it funded) and practical cost savings a distant second.

burnte 9y ago

The political and public will isn't there to spend hundreds of billions of dollars to do it. Luckily with SapceX and Blue Horizon making things so much cheaper, we can get that will back.

Nomentatus 9y ago

True, we haven't launched THAT many rockets or kinds of rockets: but according to Musk, oligopolies and rent-seeking has been most of the problem keeping us stuck; with everything from sourcing Aluminum to finding a better way than just milling a huge chunk of it, and on and on. No real competition, so little real research or change, and providing that was his motivation to throw his hat into the ring.

marktangotango 9y ago

I'll throw out another answer no has mentioned yet; those cats back in the 60's were good, damned good. They did an exceptional job with what they had. Recall the SR-71 is from that era as well.