《那些古怪又讓人憂心的問題》第19期:太空潛水艇(3)
Okay-technically, a submarine does have rockets.
Unfortunately, the rockets are pointing the wrong way to give the submarine a push. Rockets are self-propelling, which means they have very little recoil. When a gun fires a bullet, it's pushing the bullet up to speed. With a rocket, you just light it and let go. Launching missiles won't propel a submarine forward.
不幸的是，潛艇上的“火箭”的朝向不對，沒法把潛艇推離軌道。火箭靠自身攜帶的燃料推進，意味着發射火箭的後坐力極小。當槍射出子彈時，槍其實在把子彈向前推。但如果是火箭的話，你只是啓動了火箭，然後它就自己飛走了。發射艇載導彈並不能向前推動潛艇。But not launching them could.
但如果你不發射的話卻可以。
If the ballistic missiles carried by a modern nuclear submarine were taken from their tubes, turned around, and placed in the tubes backward, they could each change the submarine's speed by about 4 meters per second.
如果把現代核潛艇中搭載的彈道導彈從發射管中取出來，調個頭再塞回發射管中並點火，那麼每枚導彈都能使潛艇的速度提升改變約每秒4米。A typical de-orbiting maneuver requires in the neighborhood of 100 m/s of delta-v (speed change), which means that the 24 Trident missiles carried by an Ohio-class submarine could be just enough to get it out of orbit.
典型的脫離軌道機動需要使速度降至大約每秒100米，這意味着“俄亥俄級”核潛艇上搭載的24枚“三叉戟”導彈就足夠使自己脫離地球軌道了。Now, because the submarine has no heat-dissipating ablative tiles, and because it's not aerodynamically stable at hypersonic velocities, it would inevitably tumble and break up in the air.
脫離軌道後，由於潛艇並不配備散熱用的隔熱瓦，在超音速下也不具有空氣動力穩定性，因而它將不可避免地開始翻轉並在空中解體。If you tucked yourself into the right crevice in the submarine-and were strapped into an acceleration couch-there's a tiny, tiny, tiny chance that you could survive the rapid deceleration. Then you'd need to jump out of the wreckage with a parachute before it hit the ground.
如果你能擠進一個正確的縫隙中，並且把自己綁在加速度座椅上，那麼你有很小很小很小的機率能夠撐過劇烈的減速階段。之後你需要在潛艇撞擊到地面之前帶上一個降落傘跳出殘骸。If you ever try this, and I suggest you don't, I have one piece of advice that is absolutely critical:
如果你真的打算這麼做（我並不推薦），有一個絕對重要的事情你需要牢記在心：Remember to disable the detonators on the missiles.
記得解除導彈上的引爆裝置。1 This is why, even though matches and torches are about the same temperature, you see tough guys in movies extinguish matches by pinching them but never see them do the same with torches.
1． 這也是爲什麼即使火柴和火炬的火焰溫度差不多，在電影中你只會看到那些大塊頭們用手一捏就能滅了火柴，但絕不會看到他們對火炬做同樣的事情。2 Or conduction.
2． 通過熱傳導流失的熱量也變少了。3 This is my single favorite word in the English language. It means the warmth of sunlight in winter.
3． apricity，這是我最喜歡的一個英文單詞，它的意思是冬日裏的陽光。4 When they moved into the Sun, the sub's surface would warm, but they'd still be losing heat faster than they'd be gaining it.
4． 當他們朝太陽方向運行時，潛艇的表面會升溫，但整體熱量流失的速度仍然大於熱量獲取的速度。
