As late as 1820, the universe was thought by European scientists to be 6,000 years old. It is now thought to be between 15 billion and 20 billion years old.
直到1820年，欧洲的科学家们还认为宇宙只有6000岁。现在认为已由150到200亿岁。


Up to 150 tons of meteorite fragments slam into Earth every year. As far as is known, only seven people have been struck by such rocks from space.
每年有多达150吨的陨石碎片袭击地球，可是迄今为止已知只有7个人被这种来自太空的石头打中。

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