Hello, SFIA audio listeners. In this month's Nebula exclusive, big alien theory,

we're asking 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.

This episode is brought to you by World Anvil.

When it comes to adopting nuclear energy, the saying goes that the best time to plant a reactor

was yesterday, and the next best time is today.

So today we were looking at nuclear power, and how and if we should finally embrace as a major

energy source after decades of controversy and association with nuclear weapons.

This episode comes out on August 5, 2021, 76 years after the first and only use of atomic

weapons in warfare at Hiroshima and Nagasaki on August 6 and 9th of 1945, respectively.

A full human lifetime has passed since then, and was still not sure how many people died

during the attack itself, or from radiation-related illnesses afterward, but most figures put

it well over 100,000. Thankfully no other atomic weapons has seen battlefield use, though that

would have been surprising to most folks who lived during the Cold War that followed.

I was 10 years old when the Berlin Wall fell, an event that is usually seen as the end of the

Cold War, in much the same way Hiroshima and Nagasaki are seen as the end of World War II,

and prior to that it was taken as a given by

so many people that atomic warfare would be the death of our civilization, and probably

sooner than later. Taking in that context, it makes sense why nuclear energy seemed to be an

easy cell during the Cold War when nuclear technology was already being mass produced, and is

at least partially at fault for much

...