They would have been almost pure hydrogen — the primary ingredient of thermonuclear fusion, which makes a star shine.

它们可能曾经几乎完全是由氢元素构成的，氢元素是热核融合的主要原料，正是这种反应让星星放出光芒。

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At this point the pressure at its center will become so great that runaway fusion occurs and the star will detonate in a thermonuclear supernova.

在这个极限点上，其中心压力将变得如此巨大，以至于爆发失控的核聚变，而恒星则爆炸成为热核爆炸型超新星。

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The real Holy Grail for an interstellar mission will be breakthroughs in our ability to harness thermonuclear energy — namely fusion.

一个星际的任务真正的圣杯将是我们在热核能利用能力上的突破——就是核聚变。

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Tritium is also used as a component in the triggering mechanism in thermonuclear (fusion) weapons.

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Another possibility--the most disturbing one, actually--is that the North Koreans had been telling the truth when on May 12, just two days before South Korea detected the high levels of xenon, they announced they had created a nuclear fusion reaction, a step necessary to the building of a thermonuclear device.

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