That's due to the heat that remains in the nuclear core, both from the recently-disabled but still-hot fuel rods and from the various byproducts of the fission process.

燃料棒虽然停止工作，但仍然非常炙热，而且裂变反应生成的多种副产物也会产生很多热量，这些热量一直维持在反应堆的核心。

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Nuclear fission produces insane amounts of energy — we're talking several million times more energy than you'd get from a similar mass of a more everyday fuel like gasoline.

核裂变产生的能量极其巨大——相比同等质量的普通燃料如汽油等，核裂变材料释放出的能量要多出几百万倍。

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The uranium fuel generates heat by neutron-induced nuclear fission.

铀燃料是由中子导致的核裂变产生的能量加热的。

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Nuclear fission avoids using large quantities of fossil fuel for energy but is very contentious because it produces radioactive waste.

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Thermoelectric coupling uses heat from the decay of a radioactive fuel (as opposed to the full-scale nuclear fission which powers a reactor on Earth) as its energy source.

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Reactors that exploit nuclear fission (in which energy is generated by splitting uranium atoms) have produced thousands of tonnes of spent fuel and other radioactive by-products.

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