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Of course it's less capable than Apollo - we don't have anywhere near the lift capability of Saturn V anymore, and this program's budget is a rounding error in

Of course it's less capable than Apollo - we don't have anywhere near the lift capability of Saturn V anymore, and this program's budget is a rounding error in the $200B (inflation-adjusted) that went into Apollo. I think people underestimate just how insane the investment was in that program: in the neighborhood of 0.25% of GDP for a decade.

sandworm101 7y ago
I think people underestimate the rocket equation. In the last fifty years very little progress has been made on the basic ratios between rocket fuel, size and payload. If you want to land on the moon, in 1960 or 2026, you are still going to need the same amounts of fuel and supplies. Your landers will by necessity be similar too.
- azernik 7y ago
  At least for launch, I doubt we'll improve those mass ratios for a long time to come - chemical rockets hit theoretical limits at exhaust velocities/specific impulses of e.g. ~5.5km/s for hydrolox, and SSME already got within 10-20% of that theoretical maximum. All of the systems that can get better specific impulse, like thermal rockets or electric thrusters, have thrust:mass ratios waaaaay too low to get off of Earth on their own. (Possibly nuclear thermal rockets? But I don't think people will be overjoyed firing those off in an atmosphere.)
  - grey-area 7y ago
    If you reuse vehicles and refuel in orbit, you don't need to be more efficient.
- maccam94 7y ago
  Sure, but rocket launch costs are orders of magnitude higher than the cost of fuel to launch payloads. Once we nail down reusability, then we'll see space access become much more affordable. And once we have ships that only operate in space, we'll be able to carry much more fuel along (aerodynamics and structural strength are much less important).
  - azernik 7y ago
    The problem is that, no matter how cheap your fuel is, you have to build a launcher that can lift off while carrying all that fuel. It's expensive to make a pressure vessel that strong and light and large, engines that powerful, etc. If launch gets cheap enough given current launcher sizes, you can get into in-orbit assembly, but that requires immense investment into robotics or a lot of spending to support (machine-assisted) human construction workers. i.e. you can't launch Apollo as a single package on Falcon 9s no matter how many you can afford, and if you want to send it up in multiple packages you need to either make the spacecraft bigger and bulkier and more expensive so that it's modular, or send up a few times the mass of the resulting spacecraft in assembly robots or construction workers' habitats. (That's why Starship is so exciting even if it doesn't end up meeting Musk's cost targets, and why SLS has been so enticing for NASA despite its shitshow of a development process - putting up a single large payload in one launch is an advantage in and of itself.)
    - fpoling 7y ago
      Most of the weight of Apollo package at the low earth orbit was fuel. Fueling in space was not considered I suppose as this was too difficult with technologies from sixties. These days it is considered possible, so launching Apollo-size package to the Moon should be possible with much smaller rockets and refueling in the orbit.
    - cstross 7y ago
      Please note that the ISS was assembled on orbit from many small components and subassemblies: the largest module was IIRC about 22 tonnes, while the ISS itself is around 420 tonnes. The Soviets pioneered this with Mir, and ISS was designed around a core that was originally intended to be Mir 2.0. So we have quite a bit of experience assembling one big structure in orbit—a 25 year learning experience, basically, which has given us a toolbox of standards for docking adapters, compatible modules, external manipulators based on the Canadarm, and experience in on-orbit refueling and resupply. Starship is big and (in theory) cheap, yes, but it's not obvious that we can't do this stuff with smaller and pricier tools. Apollo didn't go for on-orbit assembly because they were in a blinding hurry (JFK set the "by the end of the decade" goal in 1961-ish) and it's taken us 25 years of plodding to get there. But we could do it now.
- grey-area 7y ago
  If you have large reusable rockets and refuelling, you can carry a lot more. Thankfully SpaceX is working on just such a plan, which would mean landing far more mass on the moon and being able to take a lot back. Their lander will look completely different (starship).
- Tepix 7y ago
  The biggest changes will be in-orbit refueling and rapid reusability. That makes 100 tons to Mars orbit feasible.
peterlk 7y ago
I think most people (myself included) do not understand how much technological improvement costs. Anecdote: I once had a conversation with a guy who worked at ITER, and he was pretty bullish (and he had no reason to bullshit me) on the prospect of fusion as a viable energy source, but frustrated with the internal politics of ITER. So I asked, "well, what would it take? If I could call up a bunch of rich people to get funding, how much would it take?" He casually said, "oh, probably 1.2 to 1.5 trillion dollars". And then I understood why it was a multinational conglomerate that was funding it, and not a bunch of rich people.
- BronSteeDiam 7y ago
  Isn’t that just another way of saying the ITER approach is infeasible? So it’s basically a jobs program
  - godelski 7y ago
    I haven't met a fusion scientist that thinks ITER isn't going to work. Ones that don't like ITER just think there are better ways.
  - lmm 7y ago
    Compared to the world's energy costs, it's small potatoes. Fusion will be ready when the world needs it.
    - usrusr 7y ago
      > Fusion will be ready when the world needs it. 50 years ago?
- rak00n 7y ago
  2016 estimation for the project was $20B [1]. Your number is over 50 times larger. [1] https://www.bloomberg.com/news/articles/2016-06-15/world-s-biggest-science-experiment-seeks-more-time-and-money https://www.bloomberg.com/news/articles/2016-06-15/world-s-b...

sandworm101 7y ago

I think people underestimate the rocket equation. In the last fifty years very little progress has been made on the basic ratios between rocket fuel, size and payload. If you want to land on the moon, in 1960 or 2026, you are still going to need the same amounts of fuel and supplies. Your landers will by necessity be similar too.

azernik 7y ago
At least for launch, I doubt we'll improve those mass ratios for a long time to come - chemical rockets hit theoretical limits at exhaust velocities/specific impulses of e.g. ~5.5km/s for hydrolox, and SSME already got within 10-20% of that theoretical maximum. All of the systems that can get better specific impulse, like thermal rockets or electric thrusters, have thrust:mass ratios waaaaay too low to get off of Earth on their own. (Possibly nuclear thermal rockets? But I don't think people will be overjoyed firing those off in an atmosphere.)
- grey-area 7y ago
  If you reuse vehicles and refuel in orbit, you don't need to be more efficient.
maccam94 7y ago
Sure, but rocket launch costs are orders of magnitude higher than the cost of fuel to launch payloads. Once we nail down reusability, then we'll see space access become much more affordable. And once we have ships that only operate in space, we'll be able to carry much more fuel along (aerodynamics and structural strength are much less important).
- azernik 7y ago
  The problem is that, no matter how cheap your fuel is, you have to build a launcher that can lift off while carrying all that fuel. It's expensive to make a pressure vessel that strong and light and large, engines that powerful, etc. If launch gets cheap enough given current launcher sizes, you can get into in-orbit assembly, but that requires immense investment into robotics or a lot of spending to support (machine-assisted) human construction workers. i.e. you can't launch Apollo as a single package on Falcon 9s no matter how many you can afford, and if you want to send it up in multiple packages you need to either make the spacecraft bigger and bulkier and more expensive so that it's modular, or send up a few times the mass of the resulting spacecraft in assembly robots or construction workers' habitats. (That's why Starship is so exciting even if it doesn't end up meeting Musk's cost targets, and why SLS has been so enticing for NASA despite its shitshow of a development process - putting up a single large payload in one launch is an advantage in and of itself.)
  - fpoling 7y ago
    Most of the weight of Apollo package at the low earth orbit was fuel. Fueling in space was not considered I suppose as this was too difficult with technologies from sixties. These days it is considered possible, so launching Apollo-size package to the Moon should be possible with much smaller rockets and refueling in the orbit.
  - cstross 7y ago
    Please note that the ISS was assembled on orbit from many small components and subassemblies: the largest module was IIRC about 22 tonnes, while the ISS itself is around 420 tonnes. The Soviets pioneered this with Mir, and ISS was designed around a core that was originally intended to be Mir 2.0. So we have quite a bit of experience assembling one big structure in orbit—a 25 year learning experience, basically, which has given us a toolbox of standards for docking adapters, compatible modules, external manipulators based on the Canadarm, and experience in on-orbit refueling and resupply. Starship is big and (in theory) cheap, yes, but it's not obvious that we can't do this stuff with smaller and pricier tools. Apollo didn't go for on-orbit assembly because they were in a blinding hurry (JFK set the "by the end of the decade" goal in 1961-ish) and it's taken us 25 years of plodding to get there. But we could do it now.
grey-area 7y ago
If you have large reusable rockets and refuelling, you can carry a lot more. Thankfully SpaceX is working on just such a plan, which would mean landing far more mass on the moon and being able to take a lot back. Their lander will look completely different (starship).
Tepix 7y ago
The biggest changes will be in-orbit refueling and rapid reusability. That makes 100 tons to Mars orbit feasible.

peterlk 7y ago

I think most people (myself included) do not understand how much technological improvement costs. Anecdote: I once had a conversation with a guy who worked at ITER, and he was pretty bullish (and he had no reason to bullshit me) on the prospect of fusion as a viable energy source, but frustrated with the internal politics of ITER. So I asked, "well, what would it take? If I could call up a bunch of rich people to get funding, how much would it take?" He casually said, "oh, probably 1.2 to 1.5 trillion dollars". And then I understood why it was a multinational conglomerate that was funding it, and not a bunch of rich people.

BronSteeDiam 7y ago
Isn’t that just another way of saying the ITER approach is infeasible? So it’s basically a jobs program
- godelski 7y ago
  I haven't met a fusion scientist that thinks ITER isn't going to work. Ones that don't like ITER just think there are better ways.
- lmm 7y ago
  Compared to the world's energy costs, it's small potatoes. Fusion will be ready when the world needs it.
  - usrusr 7y ago
    > Fusion will be ready when the world needs it. 50 years ago?
rak00n 7y ago
2016 estimation for the project was $20B [1]. Your number is over 50 times larger. [1] https://www.bloomberg.com/news/articles/2016-06-15/world-s-biggest-science-experiment-seeks-more-time-and-money https://www.bloomberg.com/news/articles/2016-06-15/world-s-b...