Hey, it's Flora Lichten, and you're listening to Science Friday.

Think back to earlier in the month when the Artemis II astronauts sent back those spectacular

pictures from their trip around the moon. You know, there were a couple of shots of Earth that

really made us think of Carl Sagan's comments on the pale blue dot.

That's home. That's us. And with this being Earth Week, happy Earth Week to all who celebrate,

we thought it'd be a good chance to get the big picture. The really big picture. What makes Earth so special? And why are we here at all? Joining me now is astrophysicist

Hakeem O'Lushay. He's author of Why Do We Exist, The Nine Realms of the Universe, that Make

You Possible. Welcome back, Hakeem. Thank you so much for having me. We love having you. I have to say what I

loved about your book is that you broke my concept of what's needed for life. Like you took me

way beyond atmosphere, water. So I want to start big. If you're a universe, how do you build a place where we can live?

I'm guessing you need a sun, right?

You need a sun.

And for a sun, you need these giant clouds of hydrogen.

This is the sole source material from which new stars are made.

They're called giant molecular clouds.

And they're light years across,

and they birth hundreds and thousands of stars. But they themselves must come from somewhere.

And, you know, it's a huge coincidence that, you know, we have this little thing called a proton

and a thing called an electron that just happen to have, even though they're so different one from the other,

equal and opposite electric charges.

And so, you know, if electrons didn't exist,

every proton in the universe would try to get as far apart

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