我們到底可不可以觸摸月球

Twelve people have walked on the moon since humans landed there 50 years ago,but no one has ever directly touched its surface.

自人類50年前登陸月球以來，已有12個人在月球上行走過，但從來沒有人直接觸碰過月球表面。

Those astronauts wore spacesuits outside the lander.No one ever took off a glove or a boot while standing on the moon.

那些宇航員離開著陸器的時候都穿著太空服。從來沒有人站在月球上脫下過手套或靴子。

“Once we got inside and took off our suits and gloves,we did have some lunar dust on the floor,and rocks that were not bagged,”Apollo astronaut Charlie Duke,who walked on the moon in 1972,called to tell me.“On the way home,I collected the rocks floating around the spacecraft.One would come floating by,and I just picked it up and put it in my garment pocket.When I got back,I stuck them in a little jar that was about the size of a prescription bottle,and then I turned them back in to NASA.”

“我們一進到室內(nèi)，脫下太空服和手套，地板上的確會有一些月球塵埃，以及沒有裝進袋子的石頭，”1972年在月球上行走的阿波羅號宇航員查理·杜克在電話里對我說。“回家的途中，我收集了一些漂浮在宇宙飛船四周的巖石塊。有從旁邊飄過的，我就把它撿起來，放在我的衣服口袋里。回來以后，我把它們放進一個處方藥瓶大小的小罐子里，然后交給了NASA。”

Touching lunar rocks inside a spacecraft,or in a museum,is one thing;removing a glove and exposing yourself to the vacuum of space is another.In science fiction,terrible things befall such astronauts:their blood boils away,their insides get sucked out.

在宇宙飛船或博物館里觸摸月球巖石是一回事;摘掉手套，讓自己暴露在太空的真空中是另一回事。在科幻小說里，可怕的事情降臨在這些宇航員身上：他們的血液沸騰蒸發(fā)，內(nèi)臟被吸出來。

But removing a glove wouldn’t necessarily be instantly fatal.For the most part,human skin is tough enough to handle brief exposure to a vacuum.If you had a custom spacesuit with a seal around your forearm,you could probably remove your glove during a moonwalk without suffering permanent damage.

但摘掉一只手套未必會立刻致命。大多數(shù)時候，人的皮膚是堅韌的，足以應付短暫的真空暴露。如果你有一件定制的前臂密封的太空服，很可能你就可以在月球行走時摘下手套，而不至于受到永久性損傷。

It definitely wouldn’t be comfortable.In 1960,during a high-altitude balloon test,Air Force Col.Joe Kittinger’s pressure glove sprang a leak,exposing his right hand to near-vacuum conditions for several hours.His hand swelled up and went numb,but he suffered no permanent damage.

那肯定不舒服。1960年，空軍上校喬·基廷格的壓力手套在一次高空氣球測試中裂了一道口子，導致右手在接近真空的環(huán)境下暴露數(shù)小時。他的手腫了起來，失去了知覺，但并沒有因此遭受永久性損傷。

That’s how the vacuum would feel.What about the moon?Is it hot or cold?

這就是真空的感覺。那么月球上呢?它是熱還是冷?

It depends on where you’re standing.On Earth,the hottest sun-baked rocks might reach 170 degrees Fahrenheit,but on the moon—where the sun stays visible for weeks at a time,it never gets cloudy,and there’s no breeze to carry away the heat—it gets even hotter.

這取決于你站在什么地方。在地球上，被太陽炙烤的巖石最熱可能達到170華氏度(約77攝氏度)，但在月球上——日照可以連續(xù)數(shù)周，永遠不會有多云天，也沒有微風帶走熱量——它會變得更熱。

Apollo 16 landed in the lunar morning,when sun was low in the sky,but as the sun rose the ground heated up.By the time they left,Mr.Duke said,“the surface was well over 200 degrees.”The dark night side,with two weeks of darkness and no insulating blanket of air,gets colder than Antarctica in the dead of winter.

阿波羅16號是在月球的早晨著陸的，這時太陽在天空很低的位置，但當太陽升起時，地面開始變熱。杜克說，到他們離開時，“表面已經(jīng)超過200華氏度(約93攝氏度)。”處于夜晚的一側(cè)有兩周的黑夜，并且沒有空氣保溫毯，會變得比隆冬的南極還要冷。

Surprisingly,the temperature of the dust would not be a huge danger to your hand.Lunar dust is a great insulator—it’s full of hollows and crevices,and the lack of air prevents heat from flowing from one part of the soil to another(or to your skin).

意想不到的是，塵埃的溫度不會對你的手造成大的危險。月球塵埃是很好的隔熱材料——它充滿了空洞和裂縫，而缺乏空氣又防止熱量從土的一部分流向另一部分(或者流向你的皮膚)。

Based on measurements of the lunar soil and NASA guidelines on skin contact with hot objects,you would probably be able to press a bare hand against the hottest lunar soil without feeling uncomfortably warm.

根據(jù)對月球土壤的測量以及NASA關(guān)于皮膚與發(fā)熱物體接觸的指導方針，你很可能可以徒手壓在最熱的月球土壤上，而不會感到太燙。

But if your hand hit a rock,you might find yourself yanking it back in pain.It’s like when you take hot clothes straight out of the dryer:Even if all the parts of the clothes are the same(hot)temperature,the lightweight,insulating fabric feels pleasantly warm,whereas the dense,conductive zippers can burn you.

但如果你的手碰到了巖石，你可能會痛得猛縮回來。那就像你直接把熱衣服從烘干機里取出時一樣：即便衣服各個部分都是一樣(熱)的溫度，輕質(zhì)的隔熱織物讓人感到溫暖舒適，但密實的導熱拉鏈會把你燙傷。

“There’s only one time I remember feeling the heat from the lunar surface,”Mr.Duke said.The crew had left a metal frame,part of an experiment,in direct sunlight for a couple of days.“When I picked it up,I could feel the heat from that aluminum frame through my gloves.It wasn’t enough to,uh,to be worried about;you just thought,‘This thing’s really hot.’”

“我記得只有一次感受到月球表面的熱度，”杜克說。作為實驗的一部分，團隊將一個金屬架子放在陽光下直曬了兩天。“我拿起它時，能透過手套感受到鋁制架子的熱度。這還不足以，嗯，讓人擔心;你只是想，‘這東西真燙。’”

Moon dust may not burn you,but it’s no picnic.Like Earth sand,moon dust is effectively made of tiny glass shards,but the sharp edges have not been worn down by erosion.As a result,it can be pretty unhealthy.

月球塵埃也許不會灼傷你，但也不要掉以輕心。像地球上的沙子一樣，月球塵埃實際上是由細小的玻璃碎片構(gòu)成的，但尖銳的邊緣沒有因侵蝕而磨損。因此，它可能相當危險。

But so long as you avoided touching rocks or metal,washed your hands afterward and didn’t mind some temporary swelling,you could probably touch the moon and survive.

但只要你避免觸碰巖石或金屬，事后洗手，不介意一些暫時的腫脹，你很可能可以觸摸月球并且活下來。

Barefoot running is probably still a bad idea.

赤腳奔跑可能仍是個壞主意。