Comments by "Luredreier" (@Luredreier) on "Soyuz rocket failure explained by former astronaut" video.

+Hoang Lan Of course they did. However a lot of knowlege has been lost in the last few decades and NASA no longer know all the details needed to recreate some of the technology used in the moon landings. And while they don't have to start from scratch entierly they have a lot of things they have to rediscover to get back to where they where when it comes to manned space flight and heavy lifting rockets. At the same time they have a lot of new information gained from among other things ISS.
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