This is Planet Money from NPR.

A few weeks ago, we got this kind of mind-bending question.

It was from our friends at Radio Lab, which is a show about science and philosophy and, you know, just the sheer joy of curiosity.

And in this case, they were curious about growth, in particular economic growth.

How could it possibly go on forever? And can too much growth destroy us? And in trying to answer

their big question, we ended up in some pretty heady and unexpected places. Hello and welcome to

Planet Money. I'm Jeff Guo. And today, we're doing something a little bit different. We've teamed up

with Radio Lab and we're going to try to answer one of the biggest questions that often goes unsaid

in economics. Here's Latif Nasser from Radio Lab to get us started.

Hey, this is Radio Lab. I'm Latif Nasser. What got me thinking about economic growth was not all the stuff that's in the news, the tariffs, the fear of the recession, all that stuff that

everybody's talking about. What started it was a lecture I heard a little while back by, of all

people, an astrophysicist.

So I'm going to sketch what we know about Earth's history, cosmically speaking.

Her name is Sandra Faber. She goes by Sandy. Brilliant scientist. She co-authored the standard

model for thinking about how galaxies form.

She won a National Medal of Science back in 2011.

And she started the lecture by saying,

We have a pretty happy little planet to live on.

Earth is a good place to live for, let's say, of order, 100 million years at least.

Should be livable for a really, really long time.

Okay.

Except, she goes on to say, for us.

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