Listen to this audio excerpt from Elkin Norena, resident management officer, NASA’s Space Launch System Program:
1. 请收听来自美国国家航空航天局（NASA）航天发射系统项目驻场管理官员埃尔金·诺雷纳的这段音频摘录：
Your browser does not support the audio element.
2. 您的浏览器不支持音频元素。
NASA · Public Domain