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Here’s a bullet‑point summary of the National Geographic article “There’s now a 50‑50 chance this galaxy will crash into ours”, along with key quotes and a brief navigation to related coverage:
🔭 What’s New
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A recent 2025 study in Nature Astronomy shifts the predicted Milky Way–Andromeda merger from a near‑certainty to a coin‑flip outcome—about a 50% chance of collision within the next 10 billion years, not the previously assumed 4–5 billion years (National Geographic).
🌀 Why the Odds Changed
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Earlier collision forecasts ignored other cosmic players. The new simulations build in the gravitational effects of:
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Triangulum Galaxy (M33): ups merging likelihood
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Large Magellanic Cloud (LMC): pulls the Milky Way off-course, reducing collision odds (National Geographic).
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⏳ Timeline & Probability
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Direct head-on collision within ~5 billion years: less than 2% chance (Smithsonian Magazine).
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Overall merger likelihood within 10 billion years: around 50‑50 (Smithsonian Magazine).
🔊 Key Quotes
“A coin flip is the more accurate description.” — Till Sawala, co‑author, Univ. of Helsinki (National Geographic)
“There are going to be uncertainties… a probability of close to 50% that there is no Milky Way–Andromeda merger during the next 10 billion years.” (Tech Explorist)
💫 Implications
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No galactic smash-up: Milky Way may retain the ability to form new stars for longer (National Geographic).
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Even if a collision happens, individual stars are unlikely to collide due to vast distances (National Geographic).
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The Solar System won’t be directly affected—by then, Earth will likely be uninhabitable due to the Sun’s evolution (National Geographic, Reuters, New York Post).
🧬 Broader Context
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Earlier models (pre‑2025) assumed a direct collision in ~4–5 billion years based on Hubble & Gaia data (Reuters).
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The updated analysis includes 100,000 Monte Carlo simulations accounting for uncertainties in mass, position, and motion—including dark matter effects (Tech Explorist).
🔚 Bottom Line
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The long‑assumed Milky Way–Andromeda crash is no longer guaranteed.
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We face a cosmic coin flip—and the true fate of our galaxy remains uncertain, but the Solar System won’t be in danger, and Earth likely won’t even exist by then.
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