00:03:59 · Nato Saichek, Jonathan Brebner
After that you're down in the neighborhood of like, you know, you had a thousand psi behind the projectile, and the projectile's traveling at two and a half kilometers per second, you're feeling something like less than a 100 psi. You're feeling less than 10% of the the actual pressure in the gas. So what that means is you're, you know, all that energy that you put into the gas to pressurize it is is basically being wasted at that point. And two and a half kilometers per second is nowhere near the speed you need to go to space. Eight eight eight and a half kilometers per second is sort of what we target for a Space Launch System, because we're gonna need to punch through the atmosphere and get to orbital altitudes at orbital speeds. So orbital, the speed, you know, typical speeds you're talking about is something like seven and a half kilometers per second. So we expect that we'll lose like a kilometer per second punching through the atmosphere. So we need to, you know, leave the barrel at eight and a half kilometers per second so that we can get to orbit at seven and a half. I've But only described how we get to two and a half. So that's the easy part. That's the part that we did sort of [00:05:08] S0: Yeah, there's a lineage to this. We'll get to that part. So the big potato cannon had been figured out. You came up with a way to then get at that additional kilometers per second. And also presumably to reduce the g forces in such a way that you're not gonna just splatter whatever you put in the projectile. What does it sound like when it leaves the barrel?
00:05:08 · Jonathan Brebner, Nato Saichek
[00:05:08] S0: Yeah, there's a lineage to this. We'll get to that part. So the big potato cannon had been figured out. You came up with a way to then get at that additional kilometers per second. And also presumably to reduce the g forces in such a way that you're not gonna just splatter whatever you put in the projectile. What does it sound like when it leaves the barrel? [00:05:30] S1: Yeah, so we have a couple of systems that we have operational right now. One of them is a six inch diameter system that's 60 feet long. The other is a 30 inch diameter system that's 120 feet long. It's the largest cannon in the world right now. And we have we've only done one commissioning test shot. It's still... We're still in the process of of bringing it up. We insulate the system a lot. Initially, didn't insulate it a lot and it sounded like a shotgun plus a car crash. And... But we we we've added a lot of insulation to the system and now it sounds it sounds like somebody dropping a load of bricks or a shipping container, and there's a very visceral thud as you feel it in your chest and the cuffs of your pants move a little bit. The volume of air that we're moving and the rapidity with which that is happening, like there's a there's a shock wave and the whole thing is anchored to the ground and so the ground moves. [00:06:27] S0: So it's really fun to hit the the red button is what you're saying. Is. Like that has to be the best part of everyone's day is that you get to hit the red button.
00:06:27 · Jonathan Brebner, Nato Saichek
[00:06:27] S0: So it's really fun to hit the the red button is what you're saying. Is. Like that has to be the best part of everyone's day is that you get to hit the red button. [00:06:34] S1: It's a it's a it's an adrenaline it's an an adrenaline shot. And we fired the the six inch system, we fired more than a 100 times. So we've... We had a rule at one point where we we made it so that the... It was the least senior person at the company had to push the button. So that we had to... We were trying to make it so that our CEO would never push the button. That was the goal. [00:06:55] S0: Wait, hold on, why? There are two ways you can interpret that. One is you're the red shirt, so you press it. The other is this is so he's not always just only like pressing the button, we need to get everyone involved. [00:07:11] S1: It was a way to keep everyone involved. It was also sort of an ambitious goal of like, we are gonna make so much progress so fast, we're gonna grow so fast that there will always be new people, and he'll never get a chance to fire it. Unfortunately, he ended up, you know, in in... I think it was in early twenty twenty five. He had to he had to push the button. No one else... We didn't have any... Anybody who we could invite over as a visitor or something, you know, to to push the button unfortunately.
00:07:11 · Nato Saichek, Jonathan Brebner
[00:07:11] S1: It was a way to keep everyone involved. It was also sort of an ambitious goal of like, we are gonna make so much progress so fast, we're gonna grow so fast that there will always be new people, and he'll never get a chance to fire it. Unfortunately, he ended up, you know, in in... I think it was in early twenty twenty five. He had to he had to push the button. No one else... We didn't have any... Anybody who we could invite over as a visitor or something, you know, to to push the button unfortunately. [00:07:35] S0: Okay, well I volunteer. Okay. Is a problem again. All right, so there's like a history to this idea, right? So you just go back at least to Jules Verne, right? 1865 novel around this exact concept except putting people in it. That probably won't work. [00:07:50] S1: Very similar, yeah yeah. [00:07:51] S0: Germans tried to turn it into a weapon in World War II. There was a project in the 60s called Harp. Harp. And there was a project in the 80s and the 90s called Sharp. [00:08:02] S1: Right, Super Harp. [00:08:03] S0: Yeah. Super Harp. Yeah. So I guess the question is, at each of those steps people were conceptualizing it or testing various stages of it. What changed that made you think, oh now actually we can go back to this particular idea that was abandoned at various points.
00:08:03 · Jonathan Brebner, Nato Saichek
[00:08:03] S0: Yeah. Super Harp. Yeah. So I guess the question is, at each of those steps people were conceptualizing it or testing various stages of it. What changed that made you think, oh now actually we can go back to this particular idea that was abandoned at various points. [00:08:19] S1: Yeah, story with HARP is HARP worked. They were firing projectiles, Gerald Bull in the 60s and 70s was firing projectiles to orbital altitudes for $5,000 a shot, and he was getting cube sat sized masses to orbital altitudes. He had a whole system called a Martlet, which was a three stage solid rocket motor designed to put a cubesat sized object into low earth orbit. The problem was in the sixties and seventies, there was no such thing as a cubesat. In fact, there was no such thing as a commercial space industry at all. No one at that point cared a lick for the marginal cost of space launch. The only thing space launch was good for at that point was either, like, massive national prestige projects, where cost doesn't matter, or nuking somebody else. Where again, if you're ending the Earth, it doesn't matter. The marginal cost of launch doesn't matter. Know? We're gonna wipe all life out on the planet. How many times do we need to do that? I'm on a budget here. Like, nobody cares. Know? So the idea that, you know, in in... Basically, in the last, say, fifteen, twenty years [00:09:33] S0: SpaceX happens. [00:09:34] S1: SpaceX happens. [00:09:34] S0: That's big part of
00:09:34 · Jonathan Brebner, Nato Saichek
[00:09:34] S0: That's big part of [00:09:35] S1: it. A commercial, the idea that it is commercially viable to be operating stuff in space, and that cost per launch, cost per kilogram matters. And so if you were looking at the fundamental physics, like rockets are not the best way to get things into space cheap, but they are a portable way to move nukes around and be unblockable. So we invested cumulatively as a civilization, The US and the Russians, something like $4,000,000,000,000 in rocket development. And so we we, as a society, plowed a lot of resources into developing this technology. And once you're in a local optimum there, it's really hard to to get your way out of it. But basically, my co founder Mike got a lot of conviction around it, and he yelled at me a lot, and we talked about it a lot, and fought about it, and eventually we sort of hashed out this, our sort of like current architectural design, and we think that it is a plausible path to get, you know, I don't know, he quotes $10 a kilogram, but I'm like the, you know, he's the guy who keeps our eyes on the sky, and I try and keep our feet on the ground. So I'll say, you know, less than $100 a kilogram. I'll be a little bit more conservative. I think [00:10:49] S0: it What is the current cost for chemical rockets?