Secrets of the Milky Way

Our Galaxy jealously guards its secrets. And if it lets you discover any, it’s very slowly.

[Photo: Kevinmloch, CC BY-SA 4.0, via Wikimedia Commons]

We live on a huge island of glowing matter surrounded by darkness, which only a hundred years ago was the entire universe for us. That it is only one of many similar objects separated by millions of light years of vacuum, we learned only in 1923. This groundbreaking discovery, second only to the Copernican Revolution, was made by…