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The universe seems to be full of dark matter, yet no one knows what it's made of. The best guess is that invisible particles called weakly interacting massive particles, or WIMPs, contribute all this missing mass. And that idea matches the latest data generated by the Alpha Magnetic Spectrometer, or AMS experiment. This instrument lives on the International Space Station, and it may be seeing direct signs of dark matter. The study is in the journal Physical Review Letters.
宇宙中似乎充满了暗物质，但没人知道它们是由什么组成的。最佳猜想为：暗物质是由肉眼看不见的粒子——大质量弱相互作用粒子，或称WIMP组成的。该猜想与阿尔法磁谱仪计划中（即AMS计划）得出的最新数据相稳合。这台仪器被放置在国际空间站，用来观测暗物质的直接征象。该研究发表在《物理评论快报》上。
The AMS catches charged particles flying through space. Its new results show more positrons than expected. Positrons are the antimatter counterparts to electrons.
阿尔法磁谱仪观测到太空中飞行的带电粒子。最新观测结果显示，这些粒子带的正电子要比想象的多。正电子是电子的反物质。
Normal astrophysical processes create some positrons, but not as many as AMS registered. One possible explanation is that these excess positrons are a by-product of dark matter interactions. That is, they're being created by the elusive WIMPs.
正常的天体物理运动会产生一些正电子，但数量不及阿尔法磁谱仪中记录的。另一个可能的原因是：这些多余的正电子是暗物质间相互作用的副产物。也就是说，它们是由神秘的大质量弱相互作用粒子产生的。
When two WIMPs collide, they can annihilate each other, giving rise to other particles—such as positrons. The data from AMS so far match these predictions.
当两个大质量弱相互作用粒子碰撞时，它们会彼此消灭，从而产生另一些粒子——比如正电子。目前，阿尔法磁谱仪显示的数据与这些预测相稳合。
The positrons might also have a more mundane source, such as the spinning stars called pulsars. Time will tell if the space-based AMS has indeed seen the first sign of what makes up dark matter—or if we're still stuck in the dark.
也许正电子的产生原因比上述讲的还要简单，比如被命名为脉冲星的自旋恒星就是这样。时间将告诉我们：驻扎在太空上的阿尔法磁谱仪是否真的观测到了构成暗物质的直接征象——又或者说，我们仍旧对此一无所知。
