A Warped Milky Way on a Diet: How an Ancient Merger Bent Our Galaxy’s Disk
This paper shows that the Milky Way’s long-lived disk warp can be explained by an ancient merger with the Gaia-Sausage-Enceladus galaxy. Using simulations with a low-mass Milky Way, the authors find that a tilted, evolving dark matter halo drives wave-like bending of the disk. Angular momentum exchange between the halo and disk causes the warp to weaken and regenerate over billions of years.
Galactic Warps Through Time: Bending Disks from the Early Universe to Today
This study analyzes nearly 1,000 edge-on galaxies to track how common and strong vertical disk warps were over time. The researchers find that S-shaped warps were far more frequent and pronounced around 10 billion years ago, likely due to increased galaxy interactions and gas content. These results suggest warps are key indicators of a galaxy’s dynamic past.