台湾上空惊现不可思议的飞碟状云层

We are observing a phenomenon over Tainan City. It's like a perfect circle over Tainan City, a perfect circle in the sky. I would like to know what it takes what's a naturally occurring phenomenon that can create a perfect circle in the middle of the clouds. A perfectly circle glaring in the clouds over Tainan City, I don't know what it could be.
现在我们正在观察台南市上空的奇异现象。台南市的上空仿佛出现了完整的飞碟状云层。我很好奇，是什么神奇的自然现象能在云层中创造出这样完整的圆圈。我们可以看到云层中的这个圆圈向外散发着光辉，但完全不知道这是什么。