Name: 第二の地球を作るには？ (How Could We Create A Second Earth?)
Uploaded: 2021-01-14T06:35:20.000Z
Duration: 4 min 25 s
Description: VoiceTubeの動画で発音を聞きながら英語表現を覚えよう！学べる英語：

As we blow through the resources on Earth, it's clear we're going to need a new planet soon.

And since there isn't another Earth out there, is it possible we could make one through terraforming?

Terraforming is the process of turning a hostile environment into one that can support human life.

And a possible place where this could happen is Mars.

After all, it's literally right there, and might be a good replacement for Earth.

Well, Mars' atmosphere is really thin, only about one percent of what we have on Earth.

And it's carbon dioxide, so toxic to humans.

Mars is also further from the Sun and that coupled with its thin atmosphere means it's about -63 degrees Celsius.

So, sorry folks, your winter coats won't quite cut it.

On top of that, Mars also has no magnetosphere so no protection against radiation.

And it also only has about one-third of the gravity we feel on Earth.

So, clearly, there's a lot we'd need to change.

We'd have to make it thicker and change its composition.

One way to do this would be to trigger a greenhouse effect, making it so any heat from the Sun is trapped, heating the planet all over.

We could do this a bunch of different ways, like using methane mined from the rocks on Mars,

carbon dioxide -- if we could get enough of it, or even with ammonia!

Let's focus on that last one for a minute.

We could release that ammonia by smashing ice-rich comets from the outer Solar System.

And since ammonia is mostly nitrogen by weight, once we add oxygen through plant life,

we could have an atmosphere pretty similar to Earth's!

And with a thicker atmosphere, the atmospheric pressure would be high enough for human to possibly live.

From here, the atmosphere will warm the planet and the rest of the terraforming job will be a relative cakewalk.

We can melt Mars' polar ice caps and have water, and with water we can have the environment for life,

make some changes to the Martian soil, and set up shop on the formerly red planet.

Remember the whole “Mars has no magnetosphere” thing?

Turns out, that's a big part of why Mars lost its atmosphere in the first place.

Mars' global magnetic field shut down around 4.2 billion years ago,

and from there the solar wind and powerful sun explosions stripped away most the atmosphere, sending it off into space.

And that's not good, since that means there isn't a trove of carbon dioxide in the Mars rocks to release in order to trigger a greenhouse effect.

And also, any atmosphere we do add to Mars won't last.

Eventually, it'll be stripped away by radiation and solar wind, too.

And whatever wasn't would be hard to hold onto with Mars' weaker gravity.

Instead, let's check our other nearest neighbor: Venus.

Venus has a super-thick atmosphere and temperatures around 460 degrees Celsius so we'd have to change a lot of that, too.

One option is to bombard Venus with hydrogen from gas giants, creating graphite and water that would turn into global oceans.

These would dissolve produced nitrogen and lower the atmospheric pressure to something more Earth-like.

We could also terraform parts of Mercury.

There's water and organic molecules in the northern polar region, so heating the bottoms of big craters with mirrors could melt the ice.

And adding a dome on top could create a little life-bubble on a hostile planet.

The same thing could be done on the Moon, too.

We could maybe terraform Europa … well, sort of.

If we could melt the surface ice, some of the released oxygen could populate the atmosphere

and we could have a water world on our hands.

and it's even possible to terraform Titan, too, but we'd also have to create oxygen and make the moon less toxic to humans.

But all this is really hard and really far off in the future.

While I'd love to call another place in this universe my home, we should probably just protect the Earth we have now.

This video was written by space historian Amy Shira Teitel.

She makes a new video every week over on her channel, and you HAVE to check them out!

There's a link in the description if you’re on mobile.

Make sure you come back every Monday for a brand new video.

As always, I'm Blocko and this has been Life Noggin.