Hello everybody, welcome to the Mindscape podcast. I'm your host Sean Carroll.

And today we're going to talk about space travel.

One of the things that you don't necessarily appreciate when you start talking about space travel

is the very different scales that we might be talking about.

So we're not talking about traveling to other stars today anyway.

We're not even talking about the very down to earth mission of taking a gigantic rocket

and launching it into space to put up human beings or satellites.

What we'll be talking about is once you get there, once you're out in space,

let's say you're in orbit around the earth, how do you move around?

The big problem with space travel is carrying weight,

carrying mass up into space.

And if you rely on conventional methods of propulsion once you're up there,

that means you need an awful lot of fuel just to adjust your position in orbit.

So today's guest, Natalia Bailey, is an aerospace engineer who has started a new company

called Axion Systems. That's ACC-I-O-N. It's named after a spell in Harry Potter,

not after the hypothetical, small particle that could be the dark matter.

What Axion Systems is doing are building ion drive engines.

If you're of a certain age, like I am, you remember ion drives as being this way that you might

investigate interstellar travel, because an ion drive can provide a small amount of propulsion,

but for a very long time with very little fuel being wasted.

So Axion Systems is building these incredibly tiny, you know,

centimeter-sized rocket engines that can be put onto little tiny satellites, like CubeSats,

...