Milky Way has 50% chance of colliding with its neighbor
What's the story
A new study conducted by researchers from the University of Helsinki and Durham University in England, has brought forth a surprising revelation. Researchers suggest the potential for collision between our galaxy, the Milky Way, and its nearest major neighbor, Andromeda, may not be as inevitable as previously thought. There could be a 50-50 chance of this cosmic event within the next 10 billion years. Despite Andromeda's current speed of 110km/s toward us, it remains approximately 2.5 million light-years away.
Simulation study
Advanced simulations reveal new insights
The research team utilized the latest and most precise motion and mass data from the Gaia and Hubble space telescopes. They used it to simulate the movements of not only the Milky Way and Andromeda, but also two other significant galaxies in our Local Group - the Large Magellanic Cloud (LMC) and Triangulum Galaxy. These advanced simulations provided new insights into potential intergalactic interactions over billions of years.
Probability shifts
Collision probabilities fluctuate with additional galaxies
When the Milky Way and Andromeda were considered separately, a collision within the next 10 billion years occurred in just under half of the simulations. The inclusion of Triangulum Galaxy increased this probability to two-thirds. However, when simulations included both the Milky Way, Andromeda and LMC, chances dropped to one-third. A simulation involving all four galaxies resulted in a Milky Way-Andromeda merger slightly more than 50% of the time.
Timeline extension
Extended timeline for potential galactic merger
The study also found that if a collision does occur, it would likely happen much later than previously estimated. The median merger time was determined to be over 7.6 billion years in the future, significantly longer than the earlier estimate of four to five billion years. This extended timeline provides a new perspective on the potential fate of our galaxy and its cosmic neighbors.
Cosmic reshuffling
A cosmic reshuffling, not an apocalypse
A galactic merger may sound apocalyptic, but it's unlikely to be catastrophic for life forms in the galaxies. Galaxies are mostly empty space with ample room for stars to maneuver around each other. A collision would primarily result in gravitational interactions that could push stars into new orbits, and trigger increased star formation due to compressed hydrogen. The merged galaxies would lose their current spiral shapes and form one giant elliptical galaxy instead.