A bright cloud that looked like a jellyfish appeared in the sky over Florida after a rocket launch. The striking shape formed when sunlight lit up the trail left behind by the vehicle.
left behind= 意為「在離開後留下的」，在此作為後置修飾，說明飛行器通過後所殘留的尾跡（trail）。
The event happened on 13 October during a launch by the space company SpaceX. According to Nasa, the sun illuminated the rocket's exhaust plume, which is the cloud of gas pushed out by the rocket's engines.
According to= 意為「根據……」，常用於引述消息來源或官方說法（在此指 NASA）。
When the sunlight hit this rising gas high in the sky, the exhaust began to glow brightly. This combination of sunlight and rocket exhaust created the unusual jellyfish shape above the state.