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For decades, astronomers believed
that one thing was as certain as death

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and taxes: the Milky Way

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and our neighboring Andromeda
galaxy were on a crash course…

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destined to collide
in less than 5 billion years.

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That galactic smash-up 
would spark massive star

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formation, scatter
stars like cosmic billiard balls,

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and possibly throw our Sun 
into a whole new orbit.

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But now… that future
may not be so certain.

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Thanks to fresh data from NASA’s
Hubble Space Telescope and ESA’s Gaia mission,

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researchers have re-run the numbers, 
and they’re telling a different story.

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Astronomers ran 
100,000 computer simulations

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using the most precise data
available today.

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The results?

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There’s only about a 50-50 chance
of a collision

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happening within 
the next 10 billion years.

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That’s right, there’s now
a decent chance the Milky Way

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and Andromeda will simply… 
pass by each other.

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No cosmic fireworks.

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No galactic pile-up.

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Just a long, swirling orbital dance.

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Why the change?

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This new study factors in

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not just the main galaxies,
but also their massive satellite

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companions, like the Large Magellanic
Cloud and M33.

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These smaller galaxies
tug and twist the larger ones,

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disrupting the neat two-body
collision model we once relied on.

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In fact, the Large Magellanic Cloud’s
gravitational pull

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might even guide us away
from Andromeda.

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So…

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The universe may be saving us
from a collision

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we were never going to witness anyway.

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After all, Earth becomes uninhabitable
in about a billion years

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due to the Sun’s heat,
and the Sun itself burns out in five.

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But hey, you never know,
someone might still be around!

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Andromeda and the Milky Way
may eventually collide (or not)

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at the end of their orbital dance, but
the uncertainties in the simulations

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means we just can't say 
one way or the other.

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

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the universe is more complex, and more
surprising, than we ever imagined.

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Follow us on social media @NASAHubble and NASA.GOV/HUBBLE

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NASA Meatball