00:00Have you ever looked up at the night sky and wondered, are we really safe here on Earth?
00:06What if, one day, our planet got knocked off its path or even thrown out of the solar system?
00:13Sounds impossible, right?
00:15But a new scientific study warns that this is not just science fiction.
00:19Today, we are diving into a fascinating and slightly terrifying study that looks billions
00:25of years into the future.
00:28Scientists used powerful computer models to predict what might happen to Earth and its
00:33neighboring planets.
00:35What scientists found could change the way we see our place in the universe.
00:41Earth orbits the Sun along with seven other planets, countless moon, dwarf planets like
00:47Pluto, asteroids, comets, and a mysterious odd cloud way out at the age.
00:55For over 4 billion years, this dance has been stable enough to let life flourish on Earth.
01:02Studies suggest that the Sun's gravity is the main anchor.
01:06But the planets also pull on each other, subtly changing each other's orbits over millions
01:12of years.
01:13It is like eight dancers holding hands, each gently tugging at the other.
01:19If something big tugs from outside, the whole dance can pick.
01:24So if we question what could disturb this balance, the answer is passing stars.
01:30Our solar system is drifting through the Milky Way, surrounded by hundreds of billions of
01:35other stars.
01:36Every few million years, one comes relatively close.
01:41The word close might still means trillions of kilometers.
01:45But even from that distance, a star's gravity can nudge things around special objects on
01:51the outer edge.
01:53In a new study, scientists ran thousands of computer simulations looking ahead 4 billion years.
02:00They discovered something surprising.
02:02That is, the orbits of some planets like Mercury and Pluto are more unstable than we thought.
02:11Mercury has a 50-80% chance of reading off its current orbit, while Pluto might also be pushed
02:18off course over 5 billion years.
02:21Even Mars has a 0.3% chance of colliding with another planet or being ejected, and Earth,
02:28a 0.2% chance of getting thrown out of the solar system or colliding with another planet.
02:35You might think 0.2 is not much, but over billions of years, even tiny probabilities add
02:42up and the consequences would be, well, catastrophic.
02:48Here is how it might play out.
02:51Our passing stars slightly changes Mercury's orbit.
02:55Mercury then tugs on Venus or Mars, which in turn pushes Earth out of its usual path.
03:02Earth could spiral inward, getting closer to the Sun, turning our planet into a scorched wasteland.
03:09Or, Earth could drift outward, where Jupiter's immense gravity might flink it completely out
03:15of the solar system.
03:17In that case, Earth would become a rough planet, dark, frozen and lifeless, drifting through
03:24interstellar space.
03:27But even if we escape passing stars, there is another, inevitable threat, the Sun itself.
03:36About 5 billion years from now, the Sun will run out of hydrogen fuel.
03:41It will swell into a red giant, engulfing Mercury and Venus.
03:45Earth might also be swallowed, or at least roasted beyond recognition.
03:51After that, the Sun will shed its outer layers and shrink into a white dwarf, a dense, dying
03:58amber of its former self.
04:01The solar system we know today will be gone.
04:05Let us go back to the age of the solar system for a moment.
04:10In the next million years, other stars could pass closer.
04:14One candidate is Gliese 710.
04:18Expected to come within about 0.2 light years in about 1.3 million years.
04:26So how do scientists predict all this?
04:29They build detailed computer models of the solar system and run simulations thousands of
04:34times, changing the starting condition slightly each time.
04:39These models take into account the gravity of the planets, the Sun and the effects of passing
04:45stars.
04:47By looking at the result, they can see the most likely outcomes and the rare but dangerous
04:52ones.
04:53The good news, for now, Earth's orbit is stable.
04:58No known star will pass close enough in the next few thousand years to cause serious trouble.
05:04These catastrophic scenarios are mostly billions of years away.
05:09But understanding them helps scientists learn more about cosmic history and what could happen
05:15to other planets too.
05:17For now, we can look up at the night sky knowing that our home is part of a vast, beautiful and
05:24sometimes dangerous cosmic dance.
05:28If you found this video fascinating, don't forget to subscribe for more related stories.
05:33Stay tuned.
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