Hello, SFIA audio listeners.

In this month's Nebula exclusive, big alien theory,

we're asked at the reason alien civilizations might be rare

is because most aliens are huge.

To hear it and every episode early and ad-free,

plus hours of bonus content,

check out go.nebula.tv slash Isaac Arthur and use my code, Isaac Arthur.

How hard would it be to terraform Venus?

When people start talking about terraforming, Mars usually steals the spotlight.

It's colder, drier, and more barren than Earth, but at least not trying to melt your face off.

Venus, on the other hand, once thought to be a paradise planet, now has a reputation as a hellish twin.

Scorching hot, cloaked in thick clouds of carbon dioxide, and hostile to life as we know it.

But what have we been looking at it all wrong? Venus is almost exactly the same size and mass as Earth. It has similar

gravity, a rocky surface, and a thick atmosphere, albeit one that's wildly unfriendly

right now. While Mars needs to be bulked up with an atmosphere and warmed considerably,

Venus already has too much atmosphere and too much heat. The real trick is

figuring out how to take some away. And if we could pull that off, Venus wouldn't just

be habitable, it could be even more Earth-like than Mars ever could. Today we'll briefly

explore just how hard it would be to tear from Venus, looking at both the wild and the

practical ideas proposed over

the years. Along the way, we'll see why turning Venus into a second Earth might be one of

humanity's greatest and most worthwhile challenges. As our aim today is to offer a concise

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