(单词翻译:单击)
Thanks to CuriosityStream for supporting this episode! Go to CuriosityStream.com/Space to learn more.
本期《太空科学秀》由CuriosityStream赞助播出！更多学习内容，请戳CuriosityStream.com/Space。
Today, Mars looks dry, dusty, and barren. But over the years, scientists have found all kinds of evidence that the planet was once full of water.
今天的火星看起来干燥、多尘又贫瘠。但过去这些年来，科学家发现了各种证据，表明火星可能曾经水源充足。
They've found empty riverbeds, sediment deposits, and signs of water erosion, and now, they're trying to figure out if this barren rock could have once had the right ingredients to host life.
科学家发现了干涸的河床、沉积物、以及水力侵蚀的迹象。而现在，科学家正在竭力弄清楚这贫瘠的岩石是否曾含有可以孕育生命的合适材质。
The more they search, the more they discover that life totally could have been possible, and now, there's even more to think about.
他们越探寻，就越是发现火星上完全有孕育生命的可能，而现在，这一点更加切实了。
Because last week, scientists announced the first geological evidence that Mars used to have a global system of underground, interconnected lakes.
因为上周，科学家宣布发现了第一个地质学证据，表明火星曾经的相互连通的地下河流系统，贯穿全球。
Besides just being very cool from a geology standpoint, that also suggests that some low-lying regions of the planet could have been in contact with water for a long time.
这不仅是地质学方面的一个新发现，这个证据也表明，火星上一些地势较低的地区可能曾长期有水存在。
And if life ever existed on Mars, that might have been a prime spot.
如果火星上曾有生命出现的话，那可能是生活在低洼地区的生命。
If underground lakes on Mars sound familiar, it might be because of news from this summer:
如果火星地下河的字眼听起来很熟悉的话，那可能是因为今年夏天的这则新闻：
Last July, scientists announced that they had found evidence for a salty, underground lake on Mars today, hiding under the planet's south pole.
去年7月，科学家宣布他们发现有证据表明今天的火星上存在地下盐水湖，这个湖隐藏在火星南极地下。
But this discovery isn't directly related to that. This time, scientists were looking at Mars's past.
但这次发现与这个证据没有直接关系。这一次，科学家关注的是火星的过去。
And they did it by studying 24 deep craters in Mars's northern hemisphere, using data from the European Space Agency's Mars Express mission.
他们的方式是：研究火星北半球的24个很深的火山口，使用的数据来自于欧洲太空总署的火星快车号任务。
Inside them, they found channels carved into the crater walls, along with valleys where groundwater likely seeped to the surface.
在这些火山口内部，他们发现了一些通道，通入火山口壁，沿途还有山谷。山谷里的地下水深入了地表。
They also found deltas where water levels went up and down, and places where flowing water deposited sediments.
他们发现了一些三角洲，里面的水位上下沉浮。还发现了一些流水形成沉积物的地方。
In other words, they found features that could only have formed from water pooling and flowing and changing over time.
换言之，他们发现的这些特征只有可能由水在长期蓄积、流动和变化过程中形成的。
The researchers suggest that this water may have come from a network of underground lakes, which likely formed as the climate changed.
研究人员认为，这些水来自于一个地下湖形成的网络，这地下湖很有可能是随着气候变化而形成的。
As solar wind and radiation stripped a young Mars of most of its atmosphere, the planet grew frigid, and water that once flowed over the surface settled underground.
太阳风和辐射的作用让才形成没多久的火星失去了大部分大气层，所以火星开始变得寒冷，曾经流淌于地表的水渗入了地下。
This planet-wide groundwater system may have even been linked to Mars's ancient ocean, too, since the water level in these basins closely lined up with some of the old shorelines.
火星全境内的地下水系统甚至可能与火星古代的海洋有关，因为这些盆地中的水位与一些古老的海岸线紧密相关。
If the team is right, if this deep water table did cover the planet, the paper's authors think it's also possible that life could have existed underground.
如果该团队是正确的，如果这水位颇深的地下水确实曾覆盖整个火星，那么该文章的几位作者认为，还有可能的情况是：地下也曾经存在生命。
And if so, they're hopeful that there could still be signs of it in the sediment of these deep basins.
如果是这样，这些科学家认为在这些水位较深的盆地沉积物中可以找到蛛丝马迹。
It's not a totally ridiculous idea, either. As part of the study, researchers looked at images of the craters taken by tools onboard NASA's Mars Reconnaissance Orbiter.
这个想法并不离谱。研究的部分阶段里，科学家观测了这些火山口的一些图像，图像拍摄的工具来自于美国宇航局火星勘测轨道飞行器上。
Based on how the craters reflected light, the researchers were able to identify the compounds inside of them.
根据这些火山口反射光的方式，这些研究人员可以判断其内部的化合物。
And they found that five of the craters had minerals like clays and carbonates that scientists believe are related to the beginnings of life on Earth.
他们发现其中5个火山口里有矿物质，这些矿物质与黏土和碳酸盐很像。科学家认为它们与地球初始的生命有关。
So maybe there's something more down there, too.
所以，或许地下真的也有生命存在呢。
Of course, these findings are preliminary right now,
当然，这些发现目前还处于初级阶段，
and they can't prove that a groundwater network even existed, let alone had a bunch of things swimming around in it.
甚至无法证明地下水系统是否存在，更别说里面是否有生命存在了。
But as we keep developing missions to Mars, we officially have one more thing to investigate.
不过，随着我们探索火星任务的不断深入，我们又多了一项需要研究的事情。
Someday soon, we might even be able to send astronauts to sample these craters ourselves.
不久的未来，我们也许可以派宇航员去这些火山口亲自取样。
Because over the weekend, SpaceX, one of the major contenders racing to get humans to Mars, reached a major milestone.
这么说是因为这周末，太空探索技术公司（SpaceX）就要实现一个重大的里程碑了。SpaceX是实现火星载人航空的有力竞争者之一。
This weekend, the company successfully demoed their commercially-built spacecraft, the Crew Dragon, which could be used to transport humans to the International Space Station as early as this summer.
本周末，该公司成功地试飞了商用航天器——载人龙飞船。该航天器可能可以用于载人飞往国际空间站，而且可能今年夏天就能实现。
The mission was called Demo-1, and its goal was to prove that the crew capsule could launch, dock at the Space Station, and safely return to Earth.
此次任务名为“展示-1”，其目标是证明其太空舱可以在发射后与国际空间站对接，也可以安全返回地球。
It was also done to test certain steps that can't be perfectly modeled on the ground, like the capsule's automated docking system and re-entry system.
这次试飞也是为了检测一些在地面上无法精准模拟的步骤，比如太空舱的自动对接系统和重新返回系统。
The Dragon was launched early Saturday morning and was packed full of supplies and had a robotic passenger named Ripley.
载人龙飞船于周六早上发射，上面装满了物资，还有一个名叫里普利的假人。
Yes, after Ellen Ripley from Alien.
你没听错，是以外星人艾伦·里普利命名的。
And just like Ellen Ripley, Ripley's doin' just fine. Ripley wasn't all for show, though.
与艾伦·里普利的相似之处是，里普利可以完美适应。不过，不是所有细节都能对外公开。
It was decked out with sensors that would alert scientists on the ground to any forces that could be harmful or uncomfortable for a real astronaut.
假人上配有传感器，可以向地面上的科学家发出警报，提醒对航天员有害或者不利的外力出现。
SpaceX hasn't released any data from Ripley yet, but from what we know, the launch seemed to go very well.
SpaceX尚未发布与里普利有关的数据，但根据我们目前了解的情况，此次发射似乎十分顺利。
Then, on Sunday morning, just over a day later, the crew capsule began firing its thrusters to dock with the Space Station.
随后，在周日早上，也就是过了一天之后，其太空舱开始将推进器发射让其与国际空间站对接。
And even though both objects were hurtling around the Earth at some 28,000 kilometers per hour, the docking was a success!
虽然它们2个都以近2.8万公里/小时的速度围绕地球运行，但对接十分成功！
So, shoutout to those SpaceX engineers for making that happen.
所以，在此，让我们向让这一切成为可能的SpaceX工程师们致敬吧！
Once the capsule safely attached to the dock, astronauts on board the Space Station opened the hatch
太空舱成功对接后，太空舱内的宇航员就能打开国际空间站的舱门，
and climbed in to collect air samples and unload the cargo, which included equipment and, like, a thousand packets of space food.
爬进去收集空气样本并卸下物资，其中包括一些设备以及上千包太空食物。
This mission marked a few exciting firsts. It was the first launch of a commercial crew capsule and the first time a commercial spacecraft docked on the Space Station.
这次任务创下了许多个第一次纪录。这是第一次发射商用太空舱，也是第一次实现商用航天器与国际空间站的对接。
And although it had no humans on board this time, it was the also first time an American crew capsule had been launched from U.S. soil since NASA retired the space shuttles in 2011.
虽然这次舱内没有载人，但这是第一次美国的太空舱从美国本土发射，这是美国宇航局于2011年宣布一些航天飞机退役后的第一次。
For SpaceX, it's a huge step forward in its mission to send humans to space and, ultimately, to Mars as well.
对SpaceX来说，这是载人航天任务的重大进展，也是载人飞往火星任务的重大进展。
Scientists will use the data they collect from Demo-1 to prepare for Demo-2, which will deliver two American astronauts to the Space Station as early as July.
科学家将通过他们从“展示-1”中收集到的数据来为“展示-2”做准备。后者将送2名美国宇航员进入太空，最早7月就能实现。
Doesn't sound like much of a demo to me. This milestone really shows that we're entering into a new era in spaceflight.
对我本人而言这听起来不太像展示而已。这个里程碑表明，我们进入了宇宙飞行的新纪元。
As commercial companies cut costs and build increasingly capable vessels, they're revolutionizing the way we explore space.
商业公司一边节省成本，制造可行性更强的航天器，一边变革着我们探索太空的方式。
So someday, when a crew first touches down on Mars, it might be because of SpaceX or a company like it.
所以，未来某一天，如果人类能第一次着陆在火星上，那可能是因为有SpaceX这样的公司在努力。
And thanks to new results from missions like Mars Express, we know that there is a lot to learn once we get there.
此外，我们要感谢火星快车号返回的结果，这样我们才能知道抵达火星之后有这么多东西要了解。
We don't have to stop learning things while we wait, though.
所以，在等待的时候也能持续学到新东西。
There's still a lot to discover about the universe, and that's why we're excited that this episode is supported by CuriosityStream.
关于宇宙，还有很多有待发现，因此我们很高兴本期节目能得到CuriosityStream的赞助。
CuriosityStream is a subscription streaming service that offers over 2,000 documentaries and non-fiction titles from some of the world's best filmmakers, including exclusive originals.
CuriosityStream是一个可以订阅的流媒体服务，它可以提供2000多个纪录片和人文社科类视频，都来自于世界上最棒的制片人，包括一些独家视频。
They have videos on everything from technology to lifestyles, and there's plenty of space content, too.
视频内容从科技到生活方式，不一而足。此外，当然也有太空类视频。
Like, there's one called Hubble's Imager that explains how scientists turn data from the Hubble Space Telescope into those beautiful, famous images, and what they can learn from them.
比如，有一个视频叫“哈勃成像器”，里面讲解了科学家将哈勃提供的数据变为好看的出名图像，以及我们能从中学到的东西。
Which is both aesthetically pleasing and very cool. You can get unlimited access to content like this starting at 2.99 dollars a month.
这从审美学角度来让人赏心悦目，直呼过瘾。只要支付2.99美元/月的金额，就能无限制地观看这些视频了。
And as a special thank-you for supporting SciShow, you can get the first 30 days for free!
作为支持《太空科学秀》的特别感谢，我们的听众可以免费30天体验哦！
You just have to sign up at curiositystream.com/space and use the promo code space during the sign-up process.
大家只需要在curiositystream.com/space注册，并在注册时使用优惠码即可。
