Milky Way may escape fated collision with Andromeda galaxy (9 points, 10 months ago) https://news.ycombinator.com/item?id=41240641
Milky Way and Andromeda galaxies are already merging (2020) (138 points, 2022, 74 comments) https://news.ycombinator.com/item?id=30494523
Our Dazzling Night Sky When the Milky Way Collides with Andromeda in 4B Years (182 points, 2019, 120 comments) https://news.ycombinator.com/item?id=21327269
karlperera•8mo ago
Led by astrophysicist Till Sawala at the University of Helsinki, the team ran 100,000 simulations using the latest data from Hubble and Gaia space telescopes. They found that while previous predictions weren't wrong, they didn't account for all variables—particularly the gravitational influence of the Large Magellanic Cloud, which pulls perpendicular to the Milky Way-Andromeda orbit.
"We don't find that previous calculations were wrong," Sawala told ScienceAlert. "However, we now find that the earlier prediction of a Milky Way-Andromeda collision is only one of several possibilities."
The simulations show only a 2% chance of a head-on collision in the next 5 billion years. In about half the scenarios, the galaxies pass each other at distances of 500,000 light-years or more—potentially never merging at all.
What's fascinating is how this changes our understanding of cosmic certainty. As Sawala puts it, the probability went "from near-certainty to a coin flip."
What do you think—does this change how we should view cosmic predictions? And if you had to bet, would you put your money on collision or cosmic near-miss?
barbazoo•8mo ago