经济学人下载:长翅膀的切尔诺贝利(1)

In 1957 work began on Project Pluto, a treetop-skimming American missile loaded with hydrogen bombs.
1957年，冥王星计划开始，这是一个搭载了氢弹的美国导弹。

Nothing odd about that, except that the missile itself was also to be propelled by nuclear energy.
这没什么奇异之处，除了这枚导弹本身也是由核能驱动的。

A reactor on board would suck in air, heat and thus expand it, and then hurl it out of the back to provide thrust.
导弹上的反应堆吸收空气、加热并使其膨胀，然后将其从后部抛出以提供推力。

Unfortunately, this also spewed out radioactive particles— which would hardly matter in war,
不幸的是，放射性粒子也被喷出—在战争中，这几乎是没有关系的，

but meant the missile could not be tested safely, and so the project was cancelled.
但这意味无法对这枚导弹进行安全的测试，所以该计划被取消了。

America's experience has not, however, deterred Vladimir Putin, Russia's president.
但美国的经历没有打消俄罗斯总统弗拉基米尔·普京的念头。

In March 2018 he announced the development of a Pluto-like missile called Burevestnik
2018年3月，他宣布开发一种类似冥王星计划的导弹名为Burevestnik，

("petrel", a bird regarded by sailors of old as a harbinger of storms).
（即“海燕”，一种被水手们认为是暴风雨先兆的鸟）。

This has since been tested in Novaya Zemlya, and has crashed several times.
这种导弹已在新地岛进行了测试，但失败了好几次。

On August 8th there was another accident ascribed by many observers to Burevestnik.
8月8日，又发生了另一起事故，很多观察者将该事故归咎于Burevestnik。

Seven scientists perished in a rocket explosion on an offshore platform near Arkhangelsk. The damage was widespread.
7名科学家在阿尔汉格尔斯克附近的一次海上平台火箭爆炸事故中遇难。摧毁范围广泛。

Some reports suggest that on August 13th Nyonoksa, a village 40km away,
一些报道表明8月13日，在此处辐射超过背景值后，

was almost evacuated after radiation there exceeded background levels.
400米远处的一个村庄Nyonoksa几乎疏散一空。

As Michael Elleman, a missile expert at the International Institute for Strategic Studies, a think-tank,
根据智囊团国际战略研究所的一名导弹专家Michael Elleman的观察，

observes, nuclear propulsion can work in two ways. One is fission reaction—the sort used in power stations.
核能推进起作用的方式有两种。一种是裂变反应—发电站使用的方式。

But, as Project Pluto's designers found, that is tricky to fit in a missile.
但根据冥王星计划设计者的发现，这对于导弹来说是很棘手的。

The other option is radioisotope decay, which uses a substance such as polonium-218 to heat and evaporate a liquid.
另一个选择是放射性同位素衰变，即利用一种物质，如polonium-218，加热并蒸发液体。

The gas generated might be employed to propel probes through the vacuum of space,
产生的气体或许可用于推动探测器穿过真空空间

but because it produces less thrust than fission the process has not been thought suitable for missiles.
但因为它产生的推力比裂变小，因此这个过程被认为不适用于导弹。