Galactic collision ripples across eons to shape our view of the cosmos
If you look at a map of the Milky Way today, you might think our galaxy looks calm and constant. But that’s just a snapshot of this moment in celestial time. Some 10 billion years ago, scientists say, it was anything but.
At the time, our galaxy was much smaller than it is today. So when gravity drew it together with another galaxy about a fourth its size, the Milky Way churned. The two smashed together and merged. Scientists think this collision could explain the mysterious inner halo and thick disc we see in the Milky Way’s structure today.
It’s difficult to discern the remnants of the other galaxy from the original Milky Way material at a
A revolution in perspectiveGalactic archaeology
