常速英语

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The Earth is a gigantic ball of semi-molten rock, with a heart of iron as hot as the surface of the Sun. Titanic amounts of heat left over from its birth and the radioactive decay of trillion...

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[FOOTSTEPS] [MUSIC PLAYING] SEAN CARROLL (VOICEOVER): A smooth stone is given an edge and the course of life on Earth has changed forever. This was the first step on the jour...

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It's no secret that humans are the Earth's most dominant species. And, without proof of life anywhere else in the universe, we can probably consider ourselves the most dominant species in ...

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What if one side of the Earth always faced the Sun, while the other side was forever shrouded in darkness? This is What if, and here's what would happen if the Earth was tidally locked t...

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The universe is pretty big and very strange. Hundreds of billions of galaxies with sextillions of stars and planets and in the middle of it all there is earth, with you and us. But as enormo...

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Venus is often called Earth's sister planet, but I would like to say that it's Earth's evil twin because it actually has a very hellish environment. Surface temperatures are around 4...

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There are sunsets on other planets even more spectacular than the ones on Earth. What if we could see not just one, but two suns falling below the Earth's horizon? This is What if, and here...

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Friends make life good. They provide the scaffolding that makes it not just bearable but fun. They give us a sense of meaning and purpose and are a source of security, self esteem and ha...