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  • Imagine never being able to dream of

  • landing on Mars or

  • traveling to Saturn.

  • Not because it's impossible to get there, but

  • because they didn't exist.

  • Because Earth was the only

  • planet in our Solar System.

  • The other eight planets in our Solar System

  • aren't just pretty to look at,

  • or something we strive to travel to one day.

  • Even though they're

  • billions of kilometers away,

  • they've played an essential role

  • in life here on Earth.

  • So what would happen

  • if they had never existed?

  • Each planet in the solar system

  • played a vital role in the development of Earth

  • billions of years ago,

  • and they continue playing a vital role

  • in keeping Earth safe today.

  • For example,

  • take the placement of every single planet.

  • They all have their own little space in the galaxy,

  • and that's not by accident.

  • Our planets work together

  • to keep each other in place.

  • For example,

  • if Mercury and Venus ceased to exist,

  • Earth might drift closer to the Sun.

  • And if Jupiter or Saturn disappeared,

  • instead of going closer to the Sun,

  • the Earth might drift further away from it.

  • This would cause a number of issues

  • for us Earthlings.

  • Right now, we're lucky enough to live in what scientists call

  • the "Goldilocks Zone."

  • They call it that because

  • Earth sits in the range of orbits around the Sun

  • that are just right to sustain life.

  • If Earth were to move closer to the Sun,

  • it would get a little bit hot.

  • We might burn to a crisp.

  • The farther away we get,

  • the more the temperature would drop.

  • Earth would be too cold to sustain life.

  • .

  • The position of Earth in our Solar System

  • not only affects life,

  • not only affects life,

  • but everything that happens on our planet.

  • but everything that happens on our planet.

  • but everything that happens on our planet.

  • It affects our seasons,

  • the length of our days, and

  • how long our year is.

  • But unfortunately,

  • the time we wake up will be the least of our worries.

  • With Earth being the only planet in our Solar System,

  • there's no telling where it might end up.

  • We could be all the way in the back,

  • where Uranus and Neptune used to be,

  • or somewhere right up front

  • where Mercury once was.

  • It's safe to say that

  • no matter where we end up,

  • if it's not the Goldilocks Zone,

  • there's a pretty good chance there wouldn't be any life here on Earth.

  • If life did form somehow,

  • it would definitely be aquatic.

  • That's because, without

  • any other planets keeping us in check.

  • Earth's gravity would be severely different.

  • When we say 'no other planets'

  • we mean no moons either.

  • The Moon's gravitational pull

  • is responsible for the tides here on Earth,

  • without it, our waters would remain still.

  • The oceans wouldn't rise or fall, they would just

  • stay where they were.

  • So really,

  • Earth as we know it

  • wouldn't exist if there were no other planets.

  • There's virtually no chance that humanity would be living today,

  • but what if,

  • instead of the planets never existing in the first place,

  • one day they suddenly disappeared?

  • Well, apart from Earth violently moving around,

  • not knowing where to go,

  • we'd also have another huge issue to worry about.

  • It's clear that every planet is critical to life on Earth.

  • If just one planet suddenly disappeared,

  • a number of issues would go along with it.

  • There are two planets

  • that have a very special role in keeping Earth safe.

  • Jupiter and Saturn.

  • That's because while Earth is hanging out,

  • thriving with life,

  • Jupiter and Saturn are getting beat up

  • by millions of asteroids.

  • Flying throughout the solar system, there are hundreds of

  • millions of asteroids that are trying to kill Earth.

  • Luckily, we hardly see any of these,

  • and that's thanks to Jupiter and Saturn.

  • Because of their enormous size and gravity,

  • they do an excellent job of

  • pulling asteroids into them

  • so that they never make it to Earth.

  • With these planets gone,

  • Earth would be bombarded by asteroids.

  • Not good.

  • In case you've forgotten,

  • a single asteroid hit Earth millions of years ago,

  • wiping out the entire dinosaur population.

  • So this would end up being pretty bad.

  • Earth would soon be covered with massive craters,

  • and once again, life would cease to exist.

  • Luckily, you won't have to worry about any of this.

  • You can rest easy knowing that

  • Earth sits comfortably in this

  • perfect little spot in the Universe,

  • where we can all live and thrive.

  • Another thing you don't need to worry about is

  • what would happen if the Earth lost

  • oxygen for five seconds.

  • But it is fun to think about it anyway so,

  • we'll leave that story for another WHAT IF.

Imagine never being able to dream of

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如果地球是太陽系中唯一的行星呢? (What If Earth Was the Only Planet in the Solar System?)

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    林宜悉 發佈於 2021 年 01 月 14 日
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