Before this BBC podcast kicks off, I'd like to tell you about some others you might enjoy.

My name's Will Wilkin and I Commission Music Podcast for the BBC.

It's a really cool job, but every day we get to tell the incredible stories behind songs,

moments and movements, stories of struggle and success, rises and falls, the funny, the ridiculous.

And the BBC's position, at the heart of British music

means we can tell those stories like no one else. We were, are and always will be right there

at the centre of the narrative. So whether you want an insightful take on music right now, or a

nostalgic deep dive into some of the most famous and infamous moments in music, check out

the music podcasts on BBC Sounds.

Hello and thanks for downloading the more or less podcast. We're your guide to statistical

claims that seem out of this world. And I'm your Space Force Captain Tim Harford.

The loyal listener Edward wrote to more or less at BBC.co.uk, questioning a number he heard on our fellow BBC programme Inside Science.

The rate that satellites are being launched at the moment, there are going to be 100,000 up there by 2030, with them coming down at a rate of about one per hour.

The 100,000 figure comes from the European Space Agency's recent short film, Space Debris,

Is It a Crisis?

It does seem a lot, but then space is famously quite big.

We have questions, and so did Edward. Questions such as, is this really true? How many are

up there at the moment? How many are currently re-entering the atmosphere? And do they ever crash into

each other? To answer these questions, we spoke to someone who definitely knows more about this

than we do. I'm Jonathan McDowell.

I'm an astronomer at the Smithsonian Observatory on the campus of Harvard University.

And I've been studying the history of satellites

...