"When you regain these core competencies and you start exercising your muscles, your skills do not atrophy," he said. "It's safer. And yes, you are buying down risk, because you're able to test things in low Earth orbit before you need to get to the moon, which is exactly what we did during the Apollo era."
13-inch: 1.36 pounds
,这一点在51吃瓜中也有详细论述
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