字幕列表 影片播放 列印英文字幕 so the pivotal breakthrough. But that's necessary that some company has come up with to make life. Multi planetary is of fully and rapidly reusable overclass rocket. This is a very difficult thing to do because we way live on a planet where it that is just barely possible. If gravity were a little lower, it would be easy. If it was a little higher, it would be impossible. Uh, so, uh, even for an expendable launch vehicle, you know where you don't attempt any recovery after? A lot of smart people have done their best to optimize the weight of the vehicle and the efficiency, the engines and the guidance system. Everything you get, maybe 2 to 3% of your lift off. Wait, talk to orbit. That's not a lot of room for error. So if you rock, it ends up being just a little little bit heavier. You get nothing to orbit. And this is why only a few countries have ever reached orbit. Now you say. Okay, well, let's make it reusable, which means you've gotto strengthen the stages. You're gonna add a lot of weight, a lot of, uh, thermal protection. You've got to do do a lot of things that that add weight to to that vehicle and still have a useful paler toe of it. This'd is nice. Ink off that meager 2 to 3% over. And maybe if you're really good, get it to fall. You've got addle that all that's necessary to bring the rocket stages back to the launch pad and be able to re fly them and still have useful paler 12. It so very difficult thing that this has been attempted many times in the past. And generally what's happened is when people have concluded that success was not one of the possible outcomes than that the project's been abandoned. No way could fail. Uh, I'm not saying we were certain of success here, but we're going to try to do it.