Welcome to the Quanta Science podcast.

Each episode, we bring you stories about developments in science and mathematics.

I'm Susan Vallett.

Recent observations of an aging, alien, planetary system

are helping to answer the question.

What will happen to our planet when the sun dies?

That's next.

It's season three of the joy of why, and I still have a lot of questions. Like, what is this

thing we call time? Why does altruism exist? And where is Jan 11? I'm here. Astrophysicist and co-host. Ready for

anything. That's right. I'm bringing in the A team. So brace yourselves. Get ready to learn.

I'm Janelle Levin. I'm Steve Stroggatz. And this is Quantum Magazine's podcast, The Joy of Why.

New episodes drop every other Thursday.

Earth's fate rests on a coin flip.

In five billion years, our sun will balloon into a red giant star.

Melinda Sores Fortado, an astrophysicist at the University of Wisconsin-Madison,

says whether Earth survives is an open question.

Sure, Earth could be swallowed by the sun and destroyed, but maybe not.

So this is me being an astrophysicist, thinking in probabilistic space,

I would say the jury's out. There are simulations that show that it's possible and there are simulations where the Earth avoids this fate and that it's too complex to put sort of a probability that I would trust at this point in time, given how many interconnected physical

mechanisms are at play. If you'd like me to place a bet, though, and I had to choose between

one, I would choose in Gulfman. In these other scenarios, Earth escapes and is pushed further

out into the solar system. Now, a nearby planetary system has offered clues to our

...