根据以下给定的标题，为一篇英语新闻文章写一句开头的话。


NASA Finds Evidence of Water Vapor on Jupiter's Moon Ganymede.
问题：为一篇新闻文章编写一句引人入胜的开头。
In a groundbreaking discovery, NASA has found compelling evidence of water vapor on Ganymede, one of Jupiter's largest moons.