我们到底可不可以触摸月球

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

自人类50年前登陆月球以来，已有12个人在月球上行走过，但从来没有人直接触碰过月球表面。

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

那些宇航员离开着陆器的时候都穿着太空服。从来没有人站在月球上脱下过手套或靴子。

“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.”

“我们一进到室内，脱下太空服和手套，地板上的确会有一些月球尘埃，以及没有装进袋子的石头，”1972年在月球上行走的阿波罗号宇航员查理·杜克在电话里对我说。“回家的途中，我收集了一些漂浮在宇宙飞船四周的岩石块。有从旁边飘过的，我就把它捡起来，放在我的衣服口袋里。回来以后，我把它们放进一个处方药瓶大小的小罐子里，然后交给了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.

在宇宙飞船或博物馆里触摸月球岩石是一回事;摘掉手套，让自己暴露在太空的真空中是另一回事。在科幻小说里，可怕的事情降临在这些宇航员身上：他们的血液沸腾蒸发，内脏被吸出来。

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会立刻致命。大多数时候，人的皮肤是坚韧的，足以应付短暂的真空暴露。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时摘下手套，而不至于受到永久性损伤。

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，空军上校乔·基廷格的压力手套在一次高空气球测试中裂了一道口子，导致右手在接近真空的环境下暴露数小时。他的手肿了起来，失去了知觉，但并没有因此遭受永久性损伤。

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

这就是真空的感觉。那么月球上呢?它是热还是冷?

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.

这取决于你站在什么地方。在地球上，被太阳炙烤的岩石最热可能达到170华氏度(约77摄氏度)，但在月球上——日照可以连续数周，永远不会有多云天，也没有微风带走热量——它会变得更热。

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.

阿波罗16号是在月球的早晨着陆的，这时太阳在天空很低的位置，但当太阳升起时，地面开始变热。杜克说，到他们离开时，“表面已经超过200华氏度(约93摄氏度)。”处于夜晚的一侧有两周的黑夜，并且没有空气保温毯，会变得比隆冬的南极还要冷。

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，尘埃的温度不会对你的手造成大的危险。月球尘埃是很好的隔热材料——它充满了空洞和裂缝，而缺乏空气又防止热量从土的一部分流向另一部分(或者流向你的皮肤)。

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.

根据对月球土壤的测量以及NASA关于皮肤与发热物体接触的指导方针，你很可能可以徒手压在最热的月球土壤上，而不会感到太烫。

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岩石，你可能会痛得猛缩回来。那就像你直接把热衣服从烘干机里取出时一样：即便衣服各个部分都是一样(热)的温度，轻质的隔热织物让人感到温暖舒适，但密实的导热拉链会把你烫伤。

“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.’”

“我记得只有一次感受到月球表面的热度，”杜克说。作为实验的一部分，团队将一个金属架子放在阳光下直晒了两天。“我拿起它时，能透过手套感受到铝制架子的热度。这还不足以，嗯，让人担心;你只是想，‘这东西真烫。’”

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.

月球尘埃也许不会灼伤你，但也不要掉以轻心。像地球上的沙子一样，月球尘埃实际上是由细小的玻璃碎片构成的，但尖锐的边缘没有因侵蚀而磨损。因此，它可能相当危险。

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.

但只要你避免触碰岩石或金属，事后洗手，不介意一些暂时的肿胀，你很可能可以触摸月球并且活下来。

Barefoot running is probably still a bad idea.

赤脚奔跑可能仍是个坏主意。