Take some time for yourself with soothing classical music from the mindful mix, the Science of

Happiness Podcast.

For the last 20 years I've dedicated my career to exploring the science of living a happier more meaningful life and I want

to share that science with you.

And just one thing, deep calm with Michael Mosley.

I want to help you tap in to your hidden relaxation response system and open the door to that

calmer place within. Listen on BBC Sounds.

Hello just before the podcast begins I want to tell you about the assassination.

It's a new podcast series from the BBC World Service. My name's Owen Bennett Jones

and I used to be the BBC's correspondent in Pakistan and for years covered in assassinated. The assassination is all about my 10-year investigation into what happened.

There are already seven episodes with more to come.

Search for the assassination wherever you get your podcasts. So, if you look up, you can see it's sort of hazy.

There are stars, you can see the stars, but it's sort of hazy.

So that's just pollution and London.

And it means that you can see bright things, but it's quite difficult spotting galaxies.

Step on the plants.

The thing is, for today's show, we've scaled this rooftop in London specifically to sea galaxies.

This is a massive telescope. This is like the size of a boiler.

It's one of the biggest telescopes that you can buy without having a special new thing. a a bunch of galaxies that astronomers first realized something else was there.

Something invisible and mysterious, something they called dark matter.

The discovery of dark matter was essentially from looking at the coma cluster.

If you really want to see that, you'll have to stay up till 4 o'clock in the morning.

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