I'm Mariana Spring, the BBC's social media investigations correspondent.

In my podcast, I've been investigating what happened to the daughter of a conspiracy theorist who died having rejected chemotherapy.

It would mean the world to me if I could make it that she wasn't just another in the long line of people that die in this way.

How does this reflect the rise of health conspiracy theories on social media and beyond?

The new series of Mariana in Conspiracy Land.

Listen on BBC Sounds. As they descend to the surface of the moon,

as they descend to the surface of the moon during the final 13 minutes before landing, Neil Armstrong and Buzz Aldrin are in their spacesuits, visors down.

Surrounding them in their cramped cabin is an atmosphere of pure oxygen.

Apollo spacecraft's life support systems were a critical link in the chain of survival for the astronauts.

Failures here could lead to deadly consequences,

something NASA discovered at terrible cost in January, 1967.

Here's Neil Armstrong talking in 2001 with some emotion about the darkest moment in the Apollo program.

The disaster that struck Apollo 1.

A fire in pure oxygen during testing of the command module capsule on the ground at the launch pad in Florida.

A catastrophe that killed his astronaut colleagues, Gus Grism,

Roger Chaffey, and Ed White. Ed White and I, we were good friends, neighbors. Very traumatic times.

You're much more likely to accept loss of a friend in flight, but it really hurt to lose a minute

ground test. That was indictment of ourselves. I mean, we didn't do the right thing somehow.

That's doubly, doubly traumatic.

Yeah. doubly traumatic.

We choose to go to the moon. Captain, we're go for landing.

He'll get you here, go for landing, over.

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