Once the reactor has shut down, there remains "decay heat" from traces of other radioactive isotopes.

一旦反应堆关闭，它仍热存在有来自其他放射性同位素踪迹的衰变热。

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A nuclear blast is an explosion with intense light and heat, a damaging pressure wave, and widespread radioactive material that can contaminate the air, water, and ground surfaces for miles around.

核爆炸会释放出高能量的光和热，破坏力巨大的压力波，而且四处飘散的放射性物质会污染数周围英里内的空气，水，和地表。

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Unless you have a mechanism to remove that, the heat can build up and can eventually damage the radioactive fuel or the reactor.

除非你有途径将它移除，否则热量将积累并最终破坏放射性燃料或核反应堆。

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Although solar panels will work on spacecraft at that distance, the desire for sufficient energy to drive many instruments means any mission would really need to go with radioisotope thermal generators (RTGs) - solid state electrical generators powered by the heat of radioactive decay.

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The enormous heat generated by the radioactive fuel in the reactor core needs a constant flow of cold water.

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Once the reactor has shut down, there remains "decay heat" from traces of other radioactive isotopes.

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