Interstellar space is part of this process of cosmic recycling.

They travel there, investigate both interstellar space and then the planet itself,

and then return to Earth all within the span of about 40 years.

What about science of interstellar life?

Hello and welcome to the supermassive podcast from the Royal Astronomical Society with me,

science journalist, Izzy Clark and astrophysicist Dr. Becky Smedhurst.

This time we're venturing into interstellar space.

We're going to be lit in.

Ooh, I liked that.

Izzy, thank you for that.

You're welcome.

You're welcome.

What is it?

Where is it?

And what do we know about it?

And Robert Massey, the deputy director of the Royal Astronomical Society, is with us, too.

So, Robert, where exactly does the solar system stop and then interstellar space begin?

Like, I presume there's not like a boundary as such. There's not a sign. No. You are now entering. You are now entering into space. No, it's more like a

kind of fading away as you'd expect to so much as in astronomy really. So imagine the sun's gravitational

force. Okay, it's infinite, but it fades off with the square of the distance. So, you know, you get to a point where it's infinitesimal or it's not significant. One of the definitions or one of the ways we can think about it is the influence of the solar wind, so the stream of particles that comes off the sun. And that has a certain pressure, pretty low, but a certain pressure. And that drops off too as you get further and further from

the sun. And one of the definitions is that when you get to towards the, well, not the edge of the

solar system, which goes a long way, but get towards the influence of interstellar gas where those

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