Milky Way And Andromeda Galactic Smash-Up Odds Now At 50-50

Space.com

Will the Milky Way and Andromeda galaxies collide in several billion years? The odds have changed with a new study using 100,000 supercomputer simulations.   Credit: NASA's Goddard Space Flight Center Paul Morris: Lead Producer  Video Credits: Milky Way Timelapse Stock Footage Provided By Pond5/lovemushroom  Artist Rendition of Gaia Spacecraft ESA  Artist’s animation of the Sun becoming a red giant ESA/Hubble (M. Kornmesser & L. L. Christensen)  Milky Way and Andromeda Collision Simulation Visualization Credit: NASA, ESA, and F. Summers (STScI) Simulation Credit: NASA, ESA, G. Besla (Columbia University), and R. van der Marel (STScI)  Music Credit: "Lost to Eternity" by Timothy James Cornick [PRS] via BBC Production Music [PRS] and Universal Production Music

Transcript

00:00For decades, astronomers believed that one thing was as certain as death and taxes.

00:06The Milky Way and our neighboring Andromeda Galaxy were on a crash course, destined to

00:12collide in less than five billion years.

00:15That galactic smash-up would spark massive star formation, scatter stars like cosmic

00:21billiard balls, and possibly throw our sun into a whole new orbit.

00:26But now, that future may not be so certain.

00:30Thanks to fresh data from NASA's Hubble Space Telescope and ESA's Gaia mission, researchers

00:35have rerun the numbers, and they're telling a different story.

00:40Astronomers ran 100,000 computer simulations using the most precise data available today.

00:47The results?

00:48There's only about a 50-50 chance of a collision happening within the next 10 billion years.

00:54That's right, there's now a decent chance the Milky Way and Andromeda will simply pass

01:01by each other.

01:02No cosmic fireworks, no galactic pileup, just a long, swirling orbital dance.

01:08Why the change?

01:09This new study factors in not just the main galaxies, but also their massive satellite companions

01:15like the Large Magellanic Cloud and M33.

01:19These smaller galaxies tug and twist the larger ones, disrupting the neat two-body collision

01:24model we once relied on.

01:27In fact, the Large Magellanic Cloud's gravitational pull might even guide us away from Andromeda.

01:34So the universe may be saving us from a collision we were never going to witness anyway.

01:40After all, Earth becomes uninhabitable in about a billion years due to the sun's heat, and

01:44the sun itself burns out in five.

01:47But hey, you never know.

01:49Someone might still be around.

01:50Andromeda and the Milky Way may eventually collide, or not, at the end of their orbital dance.

01:56But the uncertainties in the simulations means we just can't say one way or the other.

02:02While the fate of our galaxy remains uncertain, one thing is clear.

02:06The universe is more complex and more surprising than we ever imagined.

Category

Transcript

Recommended