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  • Mars is a harsh planet.

  • Between its lack of a breathable atmosphere,

  • no protection from UV rays,

  • and temperatures that can range from a pleasant 20 to a hellish minus 153 degrees Celsius,

  • Mars ain’t the kind of place to raise your kids.

  • Science fiction thinks we can solve these problems with terraforming;

  • you know, radically engineering the planet’s climate to make it livable,

  • even though we can’t control the climate of the perfectly liveable planet were on right now.

  • No, a life on Mars will probably have to be lived indoors,

  • but we may have just the wonder-material to make that possible.

  • The material in question is silica aerogel, also known as frozen smoke.

  • At the nanoscale, aerogel has a sponge-like structure made of silica oxide.

  • Silica is the same material usually found in glass, so like glass aerogel is translucent.

  • But its porous structure means it’s 1000 times less dense than glass.

  • Filling in those nanoscopic pores is just air,

  • and it can make up as much as 99.8% of the material, making it the lightest solid in the world.

  • All these properties got scientists thinking that it may make an ideal material for a greenhouse on Mars.

  • They got the idea from a process that’s occurring there naturally already,

  • called the Solid-State Greenhouse Effect.

  • Mars has ice caps made of frozen carbon dioxide, or what you might know better as dry ice.

  • The solid CO2 traps heat in the soil underneath it, and in the spring, this warming turns the CO2 to gas.

  • It spouts out of the surface like a geyser, spraying regolith up with it

  • and leaving dark patches we can see from space.

  • So researchers asked themselves if there was a material that could produce a similar effect,

  • and they landed on silica aerogel.

  • Because it’s translucent, light can still pass through it, allowing for photosynthesis underneath.

  • But because of what its made of and how its structured, it makes an incredible insulator.

  • It’s 39 times more effective than fiberglass

  • in fact, aerogel has already been used for this purpose on Mars.

  • It’s helped keep components warm on every rover weve sent to the red planet.

  • Better still, the material also turns away UV rays that cause sunburns and damage DNA.

  • So far on paper, aerogel sounds like a key piece of a permanent Martian settlement.

  • Of course we don’t shoot things off to other planets just because it sounds nice on paper,

  • we're not Elon Musk,

  • so the scientists decided to set up an experiment as a proof of concept.

  • They shined a light tuned to mimic the sunlight on Mars

  • at a 2.5 centimeter thick sheet of aerogel in a polystyrene box,

  • and found it increased temperatures as much as 50 kelvin.

  • They speculate that if they could develop aerogel that was less smoky and let more light through,

  • they could get that number into the hundreds.

  • More warming means the aerogel can be placed at higher latitudes,

  • where there’s more frozen groundwater to melt,

  • but even the warming from current materials could be used to grow plants.

  • We could make greenhouses out of it to grow food on Mars,

  • or simply place it in the soil to encourage algal growth.

  • But as well-suited as aerogel is for the task, it’s not perfect.

  • Remember how it’s made from the same stuff as glass?

  • Well, that also makes it extremely stiff and brittle.

  • Either we’d have to combine it with other materials like plastic,

  • or we’d have to institute an extremely strictno golfingpolicy on Mars.

  • Sorry, Alan Shepard.

  • So, the scientists are going to keep experimenting.

  • The next step is to take it to the most Mars-like environments on Earth,

  • like South America’s Atacama Desert or Antarctica,

  • to see if aerogel really can make these kinds of harsh environments more hospitable.

  • If it passes muster there,

  • maybe one day small bits of Mars could be the kind of place to raise your kids, after all.

  • Just don’t play baseball little Timmy or a homerun might doom us all.

  • Thanks for watching!

  • If you want to learn more about living on Mars,

  • check out this Focal Point episode on how engineers are building 3D printed habitats for the red planet.

  • Would you live in a greenhouse on Mars even if it meant you could never return to Earth?

  • Let us know in the comments, and why not, while you're down there click subscribe as you scroll by.

  • See you next time on Seeker!

Mars is a harsh planet.

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Aerogel可能是殖民火星的關鍵,下面是方法 (Aerogel Could Be the Key to Colonizing Mars, Here's How)

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    林宜悉 發佈於 2021 年 01 月 14 日
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