66 views
•
5 years ago
0
0
Share
Save
1 appearance
Garrett Reisman is a former NASA Astronaut. He is currently a Professor of Astronautical Engineering at USC and a Senior Advisor at SpaceX.
63 views
•
5 years ago
150 views
•
5 years ago
Show all
The J.Rogan experience. We're always talking about how wrong they got the future in like Space 1999. Remember that television show? I like that show. I watch that all the time, yeah. But all those shows, like even I think Blade Runner was like now, right? Didn't we discuss this like last year, 2019? Like we got everything wrong in terms of what the timeline was. The timeline is totally wrong. But I think that the overall direction is right in a lot of this stuff. And we'll get there. I really do believe that if we don't end up killing each other or have some horrible catastrophe like an asteroid hit us, we're going to end up living in space and have that kind of Star Trek future. I mean, I really think that's our destiny as long as we don't screw it up. Man, how far out are we looking at Star Trek? Star Trek might take a while. Do we got like warp drive and all that kind of stuff? Couple hundred years. And we got to find those dilithium cracks. Captain, she's picking up. How far do you think we are? Like if you had a wide timeline of like literally being able to go on another planet? Well, you know, well, going to Mars is something we could do in a decade if we really, really, really wanted to. Elon keeps saying that. I think he's right. I mean, it's not a question of technology. The big missing piece, I think, in understanding about what that would be like is the effect of radiation on the human body. There's engineering solutions we could come up with for that. This is for the prolonged journey, the six-month journey. Yeah. Once you start talking about... So right now, like on the space station, I took a bigger radiation hit than I would have if I stayed at home. How much of a hit? The amount of dose I took was not that much. It's like a tenth of a sievert or something. I mean, it was pretty... What's a sievert? A sievert. If you take one sievert, then you're increasing your chance of getting cancer depending on your age and gender, about a couple additional percent. Can you mitigate that with supplements? Is there iodine that you take or something along those lines? There's some, maybe antioxidants, but I think that that's not a panacea. That's not going to fix this problem. It could help maybe. They say take iodine tablets, right? If you're exposed to radiation, isn't that something that they recommend? Yeah, for nuclear reactors and all that. But I think that protects a function of someone under the organs, I can't remember. But it's not going to solve this problem, but you can shield yourself with anything that has hydrogen in it. It's a pretty good shield. So water is great. When I was on the space station, I put a big water jug around my head. Really? I figured it couldn't hurt. And then liquid hydrogen or even plastic that's made this derive from hydrogen is pretty good shielding. Okay, so you could have conceivably a light plastic suit that you wear that could shield you from a lot of the radiation on the way to Mars? There's actually a company in Israel that is teaming with NASA that's going to fly these like vests to try to shield the people. You can also put it in the hull or you can have just a storm shelter because there's basically once when we're on the space station, we're above all the atmosphere, but we're still below the magnetic field of the earth. So we still enjoy a lot of protection from radiation. Once you go out of that and you go to the moon or to Mars, then you're basically hanging it out there. You're no longer protected by that. And so you're going to take either GCR, galactic cosmic radiation, which is just everywhere out there. That sounds terrible. That's bad, doesn't it? GTR, galactic cosmic radiation. That sounds really bad. Yeah. Yeah. Those are, those are ions up to, up to iron. So heavy ions that there aren't that many of them, but when they hit you, they can do a lot of damage. They have a lot of energy. They're accelerated to like near relativistic speeds, like near the speed of light. And then, and then there's a solar, then you got to worry about solar flares. SPE, solar proton events. And those don't come, those are very unpredictable. Well they're a little bit predictable with sunspot activity, but they come every once in a while and they're giant spikes. They last a couple hours to a couple days and they could totally fry you. They're even worse than the- Oh fuck. Yeah. So conceivably we could send people to Mars and halfway there they get cooked. Yeah. So you have a six month window where you have to just roll the dice? Well, so what you can do is you can have a storm shelter, right? Where you put like a lot of this shielding. And then if you, you could detect the, the, the SPE, the GCR is there all the time, but the solar events, you can, you can detect them coming and you have enough warning time to get everybody into the storm shelter. How much time do you have? Usually when you first start seeing some of the proton radiation, then you start, you have like an hour. So you got time. So you're sitting in that thing going 48 minutes from now it's coming. Yeah. And you're just like hunkering down there, probably grabbing all the water bottles you can. Wow. And depending upon how big the ejection is, you don't know how long it's going to last. Yeah. It can be a different magnitudes and different directions. And it could just kill you even if you ever have the shield, the shielding. I mean, if it's a really huge one and we didn't really have any capability of defending from it when we did Apollo and there was a between two Apollo missions, there was one of these big ones. Oh boy. And we just got lucky that it was in between. So that seems crazy. Like what a, what a nutty roll of the dice. Yeah. But again, there's, there's, and we keep getting smarter about it. And, and, and, and I think, you know, for like right now we can send you to Mars and bring you back and, and probably ballistically speaking, you'd probably have like an additional four, 5% chance of developing cancer over your lifetime, which is not like a death sentence, you know, but it's a little uncomfortable. Yeah. Yeah. But we're getting better. And, and the thing about it, there's two things about it. One would keep getting better technologies, better shielding. We can actually come up with, there's, there's ways you can do active shielding with magnet. You can create your own magnetic field around the ship. And so it almost be like Star Trek, we're like a, you know, a force, a force field or shields or whatever. So we're, we're, there's ways that maybe we could do that. There's also the other thing that we don't know. We know exactly what radiation is out there. We don't know exactly what that radiation does to humans. The best we have to go on is like data from some of the atomic bomb survivors and, and radiation workers that work in like power plants and stuff to take some dose. But it's a different kind of radiation. So right now the error bars are really big. So when we say like, oh, 5% chance of cancer, that's taking a very conservative estimate. If we can find out what it really does to humans, maybe it's a lot more benign and maybe we could sharpen that pencil and say, yeah, it's acceptable. What if people come back smarter? What if it's like some fucking X-Men type shit? Yeah, maybe you could like, you know, I mean, radiation is always bad in real life. But always good in comic books. Yeah. We wouldn't have Spider-Man if it weren't for the Hulk. Hulk, Spider-Man, so many superheroes, they were involved in some sort of an accident. Wasn't Doctor Manhattan, wasn't that a thing with him as well? I think so. Yeah, I think so. I think from the Watchmen, I think he became who he is because of an accident. Doctor, I believe so. And I was hoping that, you know, I was up, I had my kids after I did that flight. Uh-oh. So I'm hoping that they would like one day- What if they're genius kids? Yeah. How old are your kids now? I got a nine-year-old boy and a two-year-old girl. Notice anything unusual about them? I did notice one day the two-year-old girl was concentrating on her blocks and one of them started floating, but you know what I mean? Man.