《那些古怪又讓人憂心的問題》第17期:太空潛水艇(1)

ORBITAL SUBMARINE

太空潛水艇

Q. How long could a nuclear submarine last in orbit?

Q．核潛艇在近地軌道太空中能堅持多久？

-Jason Lathbury

——賈森•拉思伯裏

A. THE SUBMARINE WOULD BE fine, but the crew would be in trouble.

A．潛艇本身不會有什麼問題，但裏面的艇員可就有麻煩了。

The submarine wouldn't burst. Submarine hulls are strong enough to withstand 50 to 80 atmospheres of external pressure from water, so they'd have no problem containing 1 atmosphere of internal pressure from air.

潛艇不會在太空中爆炸。潛艇的外殼強度足以承受50～80倍大氣壓的外部水壓，所以承受內部的一個大氣壓對它來說根本不是問題。

The hull would likely be airtight. Although watertight seals don't necessarily hold back air, the fact that water can't find a way through the hull under 50 atmospheres of pressure suggests that air won't escape quickly. There may be a few specialized one-way valves that would let air out, but in all likelihood, the submarine would remain sealed.

潛艇的整個艇體應該是氣密的。雖然水密並不意味着它能防止氣體泄漏，但潛艇能在50個大氣壓下保證不漏水這一事實，應該能夠說明至少空氣不會泄漏得太快。潛艇上或許會有一些專門設計用來釋放空氣的單向閥門，但總體來說潛艇應該算是密封的。

The big problem the crew would face would be the obvious one: air.

艇員面對的問題顯而易見：空氣。

Nuclear submarines use electricity to extract oxygen from water. In space, there's no water,[citation needed ] so they wouldn't be able to manufacture more air. They carry enough oxygen in reserve to survive for a few days, at least, but eventually they'd be in trouble.

核潛艇使用電力從海水中提取氧氣。但在太空中沒有水，因而也沒法用來產生更多的空氣。潛艇上備有一些應急的氧氣儲備，可以供艇員用上幾天，但最終他們還是會面臨氧氣用盡的困境。

To stay warm, they could run their reactor, but they'd have to be very careful how much they ran it-because the ocean is colder than space.

他們可以使用反應堆來保持溫暖，不過他們需要小心掌握好尺度，因爲海洋比太空更“冷”一些。

Technically, that's not really true. Everyone knows that space is very cold. The reason spacecraft can overheat is that space isn't as thermally conductive as water, so heat builds up more quickly in spacecraft than in boats.

嚴格來說，這句話是不對的，所有人都知道太空非常寒冷。太空飛船在太空中過熱的原因在於太空的熱傳導性能不如海水，所以熱量在太空飛船中聚積的速度比在海里的更快。

But if you're even more pedantic, it is true. The ocean is colder than space.

但如果你在咬文嚼字上更進一步，這句話也是正確的。海洋確實要比太空更冷。

Interstellar space is very cold, but space near the Sun-and near Earth-is actually incredibly hot! The reason it doesn't seem that way is that in space, the definition of “temperature” breaks down a little bit. Space seems cold because it's so empty.

星際空間非常寒冷，但在太陽（或地球）附近其實是非常熱的！之所以太空看起來沒有那麼熱，是因爲“溫度”的定義在太空中有點不那麼適用。太空很冷，是因爲它太空了。