Hi everyone, welcome to Mysteries of Science. I'm Jenny, the features editor of Science and

Nature, which is the monthly magazine from the team behind the week junior. And I'm Michael, the acting

deputy editor. On this podcast, we investigate weird events, strange creatures and mysterious places.

And today we're going to shoot off into space and go on an intergalactic investigation.

Yes, something is wrong with the universe. When astronomers look through their telescopes,

they see individual stars and entire galaxies moving under the influence of an invisible force.

And this mystery material has been given the name Dark Matter, but what is it exactly?

I mean, what's it made of? Why can't we see it? How much of it is there?

Let's see if we can shed some light on it. This is Mysteries of Science.

Right. Okay, so Michael, if we're going to solve the mysteries of dark matter,

then I reckon we really need to understand what it is. Well, Jenny,, thankfully we've got two top experts here to help us out.

Hi, I'm Catherine Heymans.

I'm a professor at the University of Edinburgh and I'm also the Astronomer Royal for Scotland.

My name is Abina Hausenfielder. I'm a theoretical physicist at the Munich Centre for Mathematical Philosophy and I also have a

YouTube channel where I talk about science broadly speaking but mostly about physics and I've

written two popular science books and a lot of very technical papers.

Hi Catherine and Sabine and welcome to the show.

Maybe some of you might remember Sabine from our Quantum Weirdness episode.

So thanks for coming back to help us out again.

Can you tell us exactly what is dark matter?

Dark matter is stuff that we believe that most of the universe is made of.

But dark matter is kind of a, it's a bad term really, because it suggests that it absorbs light, like light doesn't go through, so it's dark.

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