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  • .

  • There are billions of planets in the Universe

  • that, theoretically, can support life.

  • But so far, we haven't discovered

  • any aliens out there.

  • Maybe the reason is

  • we're just looking in the wrong places.

  • What if alien life

  • isn't anything like the life we know of?

  • There is one thing that your DNA,

  • a diamond and a rubber duck

  • have in common.

  • They're all made of carbon.

  • Carbon is one of the most abundant

  • elements in the Universe.

  • On Earth, it's also the primary building block

  • of all life.

  • Carbon is so special

  • because its atoms can make four bonds

  • with another element, oxygen,

  • and form long chains of atoms,

  • called polymers.

  • But there is another element

  • that can do the same trick.

  • Not only is silicon

  • chemically similar to carbon,

  • it also makes it on the list

  • of the most plentiful chemicals

  • found in the Universe.

  • Potentially, silicon could be a building block

  • of organic alien life.

  • And we might find that life

  • in our own Solar System.

  • A candidate for hosting a silicon-based alien life

  • is hiding among the moons of Saturn.

  • Titan, the biggest of these moons,

  • has an atmosphere that's 95% nitrogen

  • and 5% methane.

  • It has no oxygen,

  • and any water it has is frozen solid,

  • because Titan receives only one percent

  • of the amount of sunlight the Earth does.

  • But silicon-based life-forms

  • wouldn't need any water.

  • Instead, they could use liquid methane

  • as the galactic elixir for their existence.

  • The lack of oxygen would also be essential

  • for such life to emerge.

  • Here's why.

  • When carbon unites with oxygen, or oxidizes,

  • as it does during a fire,

  • it turns into a gas, carbon dioxide.

  • Now, when silicon oxidizes,

  • it becomes silicon dioxide, or silica,

  • which is a solid and not a gas.

  • If Titan had oxygen in its atmosphere,

  • silicon would immediately turn into rock,

  • and no life could possibly begin in that state.

  • But Titan's atmosphere doesn't contain any oxygen,

  • giving silicon-based life a chance.

  • Most likely, if there is silicon-based life out there,

  • it would be in the form of microbes,

  • and not animal-size organisms

  • that you can see with your own eyes.

  • Scientists generally agree that

  • any silicon-based life would need

  • intense heat to survive.

  • So most likely, you'd have to dig deep

  • under the surface of Titan to find it.

  • Because of the extreme cold on Titan's surface,

  • a living being would live

  • somewhere close to the Titan's core,

  • where it's hot.

  • And hey, there are many other planets out there.

  • Some of them might have just the right conditions

  • for non-carbon-based life to thrive.

  • Because silicon doesn't get along with oxygen,

  • the metabolic processes of a silicon-based organism

  • would have to be entirely different from ours.

  • We don't know if it's even possible,

  • just as we don't know if anything

  • strictly silicon-based would have a DNA.

  • But maybe we shouldn't try applying "our" science

  • to alien life we've never encountered

  • and planets we haven't thoroughly explored.

  • Earth's conditions don't really give silicon

  • any chance to form into a life-form.

  • But if, one day, aliens came down

  • to visit us here on Earth,

  • they would probably change

  • everything we know about

  • what living organisms could be made of.

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

.

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B2 US silicon titan life carbon oxygen alien

What If Alien Life Was Silicon-Based?

  • 30 1
    minami.kuo posted on 2019/11/15
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