如此惊人的燃料需求也是为什么飞船在再入大气层时都用热防护罩而不是反推火箭来减速——一头栽入大气层是最可行的减速方式。
These outrageous fuel requirements are whyevery spacecraft entering an atmosphere has braked using a heat shield insteadof rockets-slamming into the air is the most practical way to slow down .
反推火箭