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  • What if Earth's orbit ventured as far from the Sun as Pluto,

  • and got as close to it as Venus?

  • This is WHAT IF,

  • and here's what would happen

  • if the Earth had a large, elliptical orbit.

  • The Sun has a stronger gravitational pull on us

  • than any other body in the Solar System.

  • But other planets are slightly pulling us toward themselves, too.

  • That, together with the Earth's velocity,

  • makes the planet's orbit elliptical.

  • The difference between the farthest

  • and the closest point to the Sun in our orbit

  • is less than 5 million km (3 million miles).

  • That's nothing compared to the overall distance of

  • 150 million km (93 million miles) from us to the Sun.

  • But what if that difference was much, much greater?

  • The Earth orbits the Sun at just the right distance -

  • not so far away that we turn into an icy rock,

  • and not so close that we burn to a crisp.

  • We're in the Sun's habitable zone,

  • where water can exist in liquid form.

  • Even the slightest shift in the Earth's orbit would change that.

  • The closer we got to the Sun, the more heat would hit the planet.

  • Think it would be nice to have summer all year long; everywhere on Earth?

  • I bet you'd change your mind pretty fast.

  • As the heat became more extreme,

  • all the ice on the planet would start to melt.

  • Global sea levels would rise 70 meters (230 feet):

  • enough to cover London's Tower Bridge and flood most of the planet.

  • With little land left to absorb the scorching heat from the Sun,

  • global temperatures would skyrocket.

  • Our oceans would begin to evaporate.

  • All this would leave us with a tremendous amount of carbon dioxide in the air,

  • and little to no water left.

  • As we approached the orbit of Venus,

  • the surface temperature of the Earth would go up to 460°C (860°F).

  • Being outside would give you severe burns,

  • no matter how much sunscreen you put on your skin.

  • After getting an incredible suntan on our vacation near Venus,

  • we'd head back across the Solar System all the way to Pluto.

  • The Earth would cool down on the way.

  • But it wouldn't matter for most life forms on the planet.

  • They wouldn't have survived the extreme heat.

  • Maybe, if we moved slow enough,

  • some new life form would evolve on the Earth

  • while it's traveling to the habitable zone again.

  • But that life wouldn't last too long, either.

  • The upcoming winter would be long, and very cold.

  • If there was any water left on Earth,

  • it would freeze as we reached the -220 °C (-360 °F) temperature of Pluto's orbit.

  • If the Earth kept moving at the same speed it does today,

  • it would take it about 20 years to make a full orbit -

  • from the hottest spot closest to the Sun

  • to the coldest edge of our Solar System.

  • That's if we didn't collide with any other planet on the way,

  • which isn't all that unlikely.

  • But it is likely that we'll be making this trip solo.

  • The Moon might not be able to handle the pressure

  • of this extreme orbital journey.

  • Lifeless and moonless,

  • the Earth would at least get to enjoy some spectacular views.

  • Who knows? Maybe we'd sail too close to Jupiter

  • and become one of the moons of the gas giant.

  • But that's a story for another WHAT IF.

What if Earth's orbit ventured as far from the Sun as Pluto,

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B1 中級

如果地球有一個大橢圓軌道呢? (What If Earth Had a Large Elliptical Orbit?)

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    林宜悉 發佈於 2021 年 01 月 14 日
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