Milky Way flipped in collision with dwarf galaxy 10bn years ago, astronomers say

Recent astronomical research indicates that the Milky Way galaxy underwent a dramatic disk flip during its violent early history. According to reports from The Guardian and The Times of India, this event occurred approximately 10 billion years ago. The catalyst for this shift was a massive collision with a dwarf galaxy identified as the Gaia Sausage galaxy. The force of this galactic encounter was so significant that it may have rotated the entire Milky Way disk by more than 90 degrees, effectively flipping the galaxy on its side or upside down. Multiple science and news outlets have emphasized the scale of this event.

Coverage from Sci.News, Universe Today, and ZME Science describes the event as a disk flip, while Yahoo and The Brighter Side of News highlight that the rotation exceeded 90 degrees. ScienceAlert specifically notes the unique shape of the colliding entity, referring to it as a sausage-shaped galaxy. Additionally, the Royal Astronomical Society and Phys.org characterize the movement as cosmic gymnastics, framing the collision as a pivotal moment in the galaxy's structural evolution. Contextually, this discovery matters because it suggests the Milky Way has undergone extreme instability. India Today reports that the impact was a mega crash that was powerful enough to change the path of the Sun.

This implies that the current orientation of our galactic neighborhood is the result of a violent realignment rather than a steady state of growth. The findings suggest that the early youth of our galaxy was defined by significant disruptions that altered its physical trajectory and overall alignment in space. Moving forward, observers will look for further evidence of how this collision influenced other galactic structures. While current reports from IFLScience and The Independent focus on the rotation and flip, the broader implications for the Sun's current orbital path remain a key point of interest. Future data will likely seek to refine the exact timing and degree of the flip, as astronomers continue to analyze the remnants of the Gaia Sausage dwarf galaxy and its lasting effects on the Milky Way's disk.