You're listening to Shortwave from NPR.

In a hole in the ground, there works an astronomer named Ellen Duffy.

This hole is in southeastern Australia, about 150 miles from Melbourne in a small town

called Stole.

So this is an active gold mine.

So you get your hard hat, you know, high-viz jacket, you get in the truck.

There's lots of huge machinery going on around and you drive and there's just this impossibly

ominous-looking ramp and cave structure that a tunnel that goes down deep into the earth

is completely black and you drive into this thing and then you basically go on this incredibly

long spiral.

It takes nearly 40 minutes in this vehicle to go all the way down to that operational

depth at one kilometer.

As you go, you're passing the old excavations of, you know, decade centuries in it, in

fact, past.

Collapse tunnels, old wooden structures and as you go deeper, you're seeing the more

recent digs.

All the while the tunnel is dark, there's water dripping, you have the spinning flashlight,

those are lights of the truck illuminating it.

It's incredibly atmospheric.

Alan works here because at the bottom of this mine sits a detector, a device that may

pick up faint traces of dark matter.

The mysterious particles that many scientists think make up the vast majority of matter

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