Astronomers have pondered for years why our galaxy, the Milky Way, is warped. Data from ESA’s star-mapping satellite Gaia suggest the distortion might be caused by an ongoing collision with another, smaller, galaxy, which sends ripples through the galactic disc like a rock thrown into water.
Further information on ESA website
The paper is published by Nature Astronomy: “Evidence of a dynamically evolving Galactic warp”, di E. Poggio, R. Drimmel, R. Andrae, C. A. L. Bailer-Jones, M. Fouesneau, M. G. Lattanzi, R. L. Smart and A. Spagna
Credits: TG3 Leonardo/ MEDIA INAF