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This story is part of our Cosmic Perspective special, in which we confront the staggering vastness of the cosmos and our place in it. Read the rest of the series here.
On a cold evening last October, I went into my garden to gaze at a fuzzy blob in the night sky. Unless you are in the darkest of places, this blob is so faint to the naked eye that it would be easy to convince yourself there is nothing there. I raised my binoculars to my face and an elongated smear with a bright centre appeared. This is the Andromeda galaxy, the most distant object it is possible to see with the unaided eye.
I often look at Andromeda during the winter months. But I specifically chose 6 October 2023 because it was exactly 100 years to the day since Edwin Hubble made his observations that would, just over a year later, lead him to conclude that Andromeda wasn’t part of the Milky Way but a galaxy in its own right. As I stood there, I thought about how that light had travelled 2.5 million light years to reach my eyes.
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