What's going on next door? A new study using Hubble data shows that Andromeda, our nearest major galaxy neighbor, has undergone a 500-million-year decline in star formation – with an even steeper drop in the last 40 million years: Hubble @NASAHubble · 2026-07-27 你的浏览器不支持视频播放。 0:00 / --:--