关于太空的10个惊人事实

关于太空，我们有太多美好的想象。事实上，太空就和电影里一样让人大开眼界。你知道火星的日落是蓝色的吗？你知道金星的一年比一天短吗？你知道国际空间站有多大吗？你知道向太空发射东西要多少钱吗？关于外太空，我们需要了解的还有很多。商业内幕网总结的这些太空冷知识，一起来了解一下吧。

NASA has recorded eerie space "sounds."

NASA录下诡异的“太空声音”。

NASA uses a technique called data sonification to take signals from radio waves, plasma waves, and magnetic fields and convert them into audio tracks to "hear" what's happening in space. The sounds range from ambulance-like screeches to beeps reminiscent of an alien spaceship making its approach.

NASA利用“数据可听化”技术，将无线电波、等离子体波、磁场的信号转化为音轨，从而“聆听”太空的声音，最终听到各式各样的诡异声音，如救护车警笛般的尖锐声音、让人联想起外星人飞船靠近的哔哔声等。

Sunsets on Mars are blue.

火星的日落是蓝色的。

The Curiosity Mars rover's first color photograph of a sunset in 2017 revealed a surprising twist — sunsets on Mars are blue.

2017年，“好奇号”火星探测器拍下第一张彩色日落照，这让人们惊讶地发现，原来，在火星上，夕阳是蓝色的。

NASA said this is because "dust in the Martian atmosphere has fine particles that permit blue light to penetrate the atmosphere more efficiently than longer-wavelength colors" like yellow, orange, and red.

美国宇航局表示，这是由于火星大气层的尘埃颗粒较小，散射蓝光的能力强于长波颜色（如黄色、橙色、红色）。

Launching things into space is wildly expensive.

向太空发射东西：贵得突破天际。

Payload specialist and space station engineer Ravi Margasahayam told Business Insider that each pound of cargo used to cost $10,000 to ship into space. Prices have skyrocketed since — Orbital Science's Cygnus spacecraft's cargo costs about $43,180 per pound, and SpaceX's new carriers about $27,000 per pound.

有效载荷专家、空间站工程师拉维·马加萨哈雅姆告诉商业内幕网说，一磅的货物送入太空的运费过去是1万美元（合68335元人民币）。但是自那以后运费就水涨船高，轨道科学公司天鹅座宇宙飞船每磅收费43180美元，而美国太空探索技术公司的新飞船是每磅2.7万美元。

Business Insider determined that a 16-ounce bottle of water can cost anywhere between $9,100 to $43,180 to blast into space today.

据商业内幕网计算，现在将16盎司的一瓶水送入太空的运费高达9100-43180美元。

Space is full of "space junk."

太空里全是“垃圾”。

Space is full of junk like used rocket parts and dead satellites. These objects continue to orbit Earth at about 17,500 mph — 10 times as fast as a speeding bullet.

太空里全是垃圾，如报废的火箭部件和卫星，它们继续以约17500英里的时速绕行地球——时子弹飞行速度的10倍。

The Space Surveillance Network (SSN) keeps track of how much debris is out there. The SSN is currently tracking 23,000 objects larger than a softball.

美国空间监视网一直在追踪太空中的垃圾数量，目前共有2.3万件体积大于垒球的太空垃圾。

Space junk is dangerous because one collision could trigger a chain reaction of objects hitting each other, resulting in a thick cloud of debris that would make space travel extremely dangerous.

太空垃圾非常危险，因为一旦发生碰撞，可能会造成连锁反应，由此产生的厚厚的“垃圾云”会让太空旅行变得极为危险。

The Apollo astronauts' footprints on the moon could last up to 100 million years.

“阿波罗”宇航员在月球表面留下的脚印最多可存在1亿年。

Moon rocks erode at a rate of 0.04 inches every 1 million years. This means that the astronauts' footprints on the moon from the Apollo mission in 1969 could be there for 10 to 100 million years.

月球岩石的侵蚀速率为0.04英寸（0.1厘米）/100万年。也就是说，1969年，美国宇航员执行阿波罗任务时在月球表面留下的脚印能够存在1千万到1亿年。

Space isn't always cold. In fact, it can get pretty hot.

太空不总是冰冷的，它也可以很炎热。

In the darkest parts of space, temperatures can reach -454 degrees Fahrenheit. But if you're orbiting near Earth in the sunlight, space is a toasty 250 degrees Fahrenheit. Astronauts' spacesuits are white to reflect the heat they encounter while floating above the Earth.

在太空最阴暗的地带，温度可达零下270摄氏度（零下454华氏度）；但若处于地球附近的阳光里，温度可达滚烫的120摄氏度。宇航员的太空服是白色的，在他们漂浮在地球上方时白色服装可以反射光热。

A year on Venus is shorter than a day there.

金星的一年比一天短。

Venus spins very slowly in the opposite direction of Earth — 243 Earth days for a full rotation. But it only takes 225 days to go around the sun because it's so close to it. Therefore, a year on Venus is shorter than a day.

金星自转速度很慢，而且和地球自转方向相反。金星绕太阳公转一周仅需225个地球日，因为金星离太阳很近，但金星自转一周却需要243个地球日。因此，金星的一年比一天短。

The International Space Station (ISS) is the size of a football field.

国际空间站和美式橄榄球场差不多大。

The International Space Station is 357 feet long, just three feet less than an American football field. It weighs 925,000 pounds and is the largest single human-made structure to ever enter space.

国际空间站长109米，只比美式橄榄球场少0.9米，重84万千克，是太空中迄今为止最大的人造建筑物。

The ISS has been visited by 230 people from 18 different countries to conduct research and carry out missions.

迄今为止，曾有来自18个国家的230人造访过国际空间站，开展研究和执行任务。

You would last about 15 seconds in space without a spacesuit.

若没有太空服，你能在太空中坚持15秒左右。

Because there's no pressure in space, air expands. This means the air inside your lungs would expand and tear through the tissue. And in such an extreme environment, your body would use up all of the oxygen in your blood in about 15 seconds. Other gruesome consequences of uNPRotected space exposure would include loss of bowel control, boiling blood, exploding capillaries, and bloating.

由于太空中没有压力，肺部空气会膨胀并撕裂组织。在这种极端环境中，身体会在15秒内耗光血液中的氧气。此外，还会出现种种可怕状况：大便失禁、血液沸腾、毛细血管爆裂、肿胀……

Outer space isn't empty space.

太空并非完全真空。

Besides the obvious stars and planets, you might think that the surrounding space is completely empty — a perfect vacuum devoid of all matter.

你或许认为，除了恒星、行星等天体外，太空就是不存在任何物质的真空。

It's true that space is a vacuum, but it's an imperfect vacuum because it contains a low density of particles like clouds of interstellar dust, space plasma, and cosmic rays.

没错，太空是真空的，但它并非完全真空。它还含有星际尘埃云、空间等离子体、宇宙射线等低密度物质。