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  • Imagine what it would be like

  • to have miniature version of our Sun right here on Earth.

  • This is WHAT IF,

  • and here's what would happen

  • if we built a replica of the Sun on Earth.

  • The Sun is an enormous nuclear fusion generator.

  • Every second, it fuses 620 million tons of hydrogen

  • into 606 million tons of helium in its core,

  • releasing a vast amount of energy in the process.

  • To create a replica of the Sun on Earth,

  • we'd just need to squeeze atoms of hydrogen hard enough to make them fuse.

  • Shouldn't be too hard, right?

  • Well, this fusion is only possible at extreme temperatures.

  • Even the Sun's coldest part, its surface,

  • burns at an incredible 5,500 °C (9,900°F).

  • Not even a space suit can protect you from that kind of heat.

  • But we could engineer a high-temperature superconductor

  • to tame our scorching mini-sun.

  • What would it take to bring this brighter future into reality?

  • Having an artificial sun on our hands

  • would provide us with almost limitless amounts of energy.

  • Of course, it would be much smaller than the Sun.

  • Our replica could fit inside a machine the size of 60 football fields

  • and would have the weight of three Eiffel Towers.

  • To make it work, we'd need two specific hydrogen isotopes.

  • One of them, called deuterium, we'd extract from water.

  • The other one, tritium, we'd brew from lithium during the fusion reaction itself.

  • We'd give the mini-sun its own magnetic field

  • with the help of huge magnets, at least a thousand times more powerful

  • than those you put on your fridge.

  • This field would keep the artificial sun in place

  • while we're heating it up to 150 million °C (270 million °F).

  • Few materials could handle the scorching plasma of our sun.

  • We'd have to create a robust "blanket" for it,

  • one that wouldn't melt during this scorching fusion.

  • Once we had all the engineering issues figured out,

  • the artificial sun would completely change the way our energy system works.

  • It wouldn't emit any greenhouse gases.

  • And there would be no hazardous radioactive waste left

  • to decay slowly over a thousand years.

  • Unlike fossil fuels,

  • we'd never run out of hydrogen -

  • the most common element in the Universe.

  • With this clean and safe source of energy, we'd stop adding fuel to climate change.

  • And maybe give our planet a second chance.

  • Next, we'd build fusion engines for our spacecraft

  • and go on to explore space faster than we ever imagined.

  • With hot plasma fueling up our rockets,

  • it would take us just 30 days to get to Mars.

  • Huge progress compared to a nine-month trip with our current technology.

  • Sound like science fiction?

  • What if I told you physicists around the world

  • have been working on re-creating a miniature star for decades?

  • We already have reactors capable of producing sunlike fusion.

  • But so far, none of them have produced more energy

  • than they needed to consume to make this reaction happen in the first place.

  • Everything could change with a new class of high-temperature superconductors.

  • That would bring nuclear fusion from an expensive science experiment

  • to a viable source of energy, available to everyone.

  • By the time scientists figure it out,

  • we may have moved off Earth and onto the nearest planet.

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

Imagine what it would be like

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如果我們能在地球上建造一個太陽的複製品呢? (What If We Could Build a Replica of the Sun on Earth?)

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    林宜悉 發佈於 2021 年 01 月 14 日
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