英语听力：自然百科 探索世界奥秘之Alien Neighbors (寻访外星人) Unit14（在线收听）

"...what's more, You can start to say perhaps what the planet's made of, and you can follow it in its orbit. You can understand it in much more detail."

In the future, the revamped Hubble Space Telescope may even detect planetary systems more like our own. Telescopes yet to be invented may one day confirm that we are not alone in the universe.

"It is conceivable within the next 10 to 15 years that we can directly detect these earth-sized planets that could have atmospheres, that could have oceans, we don't know. And we might also be able to sense their atmospheres from earth with telescopes to see if there is water, carbon dioxide and oxygen. And if we find carbon dioxide and oxygen, where the oxygen is in much greater abundance than the carbon dioxide, we will then speculate that photosynthesis takes place. That's the process on earth where trees and leaves convert carbon dioxide to oxygen, and then we could really begin to think there could be life. But right now, we don't even know if there’s an earth-sized planet around a star other than our own.

Future generations might witness scenes like these from an alien world. The discovery of an earth-like planet is a real possibility.

"There is no question that having discovered planets tremendously enhances our interest and the prospects of discovering intelligent life in the galaxy. And the reason is up until a few years ago, we didn't know there were any planets around any other stars. We might've been the only thing going in our galaxy."

Today, earth is still the only place where we know for sure that life exists. Humankind has the only intelligence civilization that we know about. But, there could be life out there. The mounting evidence motivates scientists to keep searching.

"Are we alone? I rather doubt it. Uh, if we are, that would be almost more fascinating to me. Uh, and so, I'm eager to continue the search and even if it's a lowly microbe that we find as our cohort in the, in the cosmos, I'll be, I'll be satisfied."

Perhaps, these are the fingerprints of a simple life form, perhaps not. Mars holds out the most hope in the solar system but then there are more than 100 billion stars in our galaxy and there are countless galaxies. If it could be shown, beyond doubt, that life evolved somewhere, anywhere other than our own home planet, then life on earth would never be the same again.

words and expressions

revamp:to change or arrange something again, in order to improve it修补, 翻新；改装.

eg:We revamped all the management system, but the business is doing no better than it was before.

in abundance:充裕

eg:Carpets are available in abundance.可供地毯货源充足。

photosynthesis :the process by which a plant uses the energy from the light of the sun to produce its own food光合作用

lowly :low in position and importance, or not respected:地位低的；级别低的

cohort:a group of people who share a characteristic, usually age:同党,同伴

beyond doubt：[常作插入语]毫无疑问