NASA reported on Aug. 19, 2026, that a study of Hubble Space Telescope data, recently published in Nature Astronomy, shows definitive evidence that a dwarf galaxy known as LKH merged with the young Milky Way during the earliest phases of its evolution. The reported collision occurred about 12 billion years ago, and the finding extends knowledge of the galaxy's history 1.8 billion years further back in time than before.

The evidence came from studying globular star clusters, according to NASA. An artist's concept released on Aug. 17, 2026, depicts the collision. The image is credited to NASA, ESA and Joseph Olmsted of the Space Telescope Science Institute.

The agency's account describes the merger as a past event reconstructed from astronomical data and presented in illustrative form. It does not report new observations of a current event.