人类即将踏上火星：未来孩子或将生活在火星上的真相揭秘

精选100篇经典TED演讲，时长8-15分钟，内容涵盖创新、成长与未来趋势。提供MP3在线播放、下载及英文文本，助你提升听力与口语。用思想的力量，点燃学习热情！下面是本期【TED】100篇经典演讲口语听力素材合集的内容，坚持积累，让你的英语更贴近生活！

Strap yourselves in. We're going to Mars. Not just a few astronauts, thousands of people are going to colonize Mars, and I am telling you that they're going to do this soon. Some of you will end up working on projects on Mars, and I guarantee that some of your children will end up living there. That probably sounds preposterous, so I'm going to share with you how and when that will happen. But first I want to discuss the obvious question, why the heck should we do this? 12 years ago, I gave a TED talk on 10 ways the world could end suddenly. We are incredibly vulnerable to the whims of our own galaxy, a single large asteroid could take us out forever. To survive, we have to reach beyond the home planet. Think what a tragedy it would be if all the humans have accomplished were suddenly obliterated. And there's another reason we should go. Exploration is in our DNA, two million years ago, humans evolved in Africa, and then slowly but surely spread out across the entire planet by reaching into the wilderness that was beyond their horizons. This stuff is inside us, and they prospered doing that.

Some of the greatest advances in civilization and technology came because we explored. Yes, we could do a lot of good with the money it will take to establish a thriving colony on Mars. And yes, we should all be taking far better care of our own home planet. And yes, I worry we could screw up Mars the way we screwed up Earth. But think for a moment, what we had when John F. Kennedy told us we would put a human on the moon—he excited an entire generation to dream. Think how inspired we will be to see a landing on Mars. Perhaps then we will look back at Earth and see that it is one people instead of many. And perhaps then we will look back at Earth as we struggle to survive on Mars and realize how precious the home planet is. So let me tell you about the extraordinary adventure we're about to undertake. But first, a few fascinating facts about where we're going.

This picture actually represents the true size of Mars compared to Earth. Mars is not our sister planet. It's far less than half the size of the Earth. And yet despite the fact that it's smaller, the surface area of Mars that you can stand on is equivalent to the surface area of the Earth that you can stand on because the Earth is mostly covered by water. The atmosphere on Mars is really thin, a hundred times thinner than on Earth. And it's not breathable, it's 96% carbon dioxide. It's really cold there. The average temperature is minus 81 degrees, although there is quite a range of temperature. A day on Mars is about as long as a day on Earth plus about 39 minutes. Seasons and years on Mars are twice as long as they are on Earth. And for anybody who wants to strap on some wings and go flying one day, Mars has a lot less gravity than on Earth and it's the kind of place where you can jump over your currents that walk around it.

Now, as you can see, Mars isn't exactly Earth-like, but it's by far the most livable other place in our entire solar system. Here's the problem. Mars is a long way away, a thousand times farther away from us than our own moon. The moon is 250,000 miles away and it took Apollo astronauts three days to get there. Mars is 250 million miles away and it will take us eight months to get there, 240 days. And that's only if we launch on a very specific day at a very specific time once every two years, when Mars and the Earth are aligned just so the distance that the rocket would have to travel will be the shortest. 240 days is a long time to spend trapped with your colleagues in a tin can.

And meanwhile, our track record of getting to Mars is lousy. We and the Russians, the Europeans, the Japanese, the Chinese and the Indians have actually sent 44 rockets there and the vast majority of them have either missed or crashed; only about a third of the missions to Mars have been successful. And we don't at the moment have a rocket big enough to get there anyway. We once had that rocket, the Saturn V, a couple of Saturn Vs would have gotten us there. It was the most magnificent machine ever built by humans and it was the rocket that took us to the moon. But the last Saturn V was used in 1973 to launch the Skylab Space Station and we decided to do something called the shuttle instead of continuing on to Mars after we landed on the moon. The biggest rocket we have now is only half big enough to get us anything to Mars.

So getting to Mars is not going to be easy and that brings up a really interesting question. How soon will the first humans actually land there? Now, some pundits think if we got there by 2050, that'd be a pretty good achievement. These days NASA seems to be saying that it can get humans to Mars by 2040. Maybe they can. I believe that they can get human beings into Mars by 2035. But frankly, I don't think they're going to bother in 2035 to send a rocket to Mars because we will already be there. We're going to land on Mars in 2027. And the reason is this man is determined to make that happen. His name is Elon Musk. He's the CEO of Tesla Motors and SpaceX.