What Surprising Phenomenon Occurs When You Look at the Night Sky?

When you look up at the night sky, you are not just observing distant stars and galaxies; you are actually witnessing the past. Because light from stars takes time to reach us, the images we see are of those celestial bodies as they were when the light first began its journey. For example, the light from Proxima Centauri, the closest star to our solar system, takes about 4.24 years to reach Earth. This means that when you look at Proxima Centauri, you are seeing it as it was over four years ago. In fact, some of the light from stars that are millions or even billions of light-years away left those stars long before human civilization existed. Thus, the night sky serves as a time machine, allowing us to glimpse the history of the universe as we observe the light that has traveled vast distances across space.