This is Science Friday. I'm Ira Flato.

A bit later in the hour, we'll be talking about the volcanic eruptions in Hawaii

and the strange species of bacteria that can eat antibiotics.

But first, the leaning tower of Pisa has been tipping for centuries.

You knew that, and you know it's managed to withstand weather and wars and earthquakes.

And while over the years, engineers have taken action to stabilize it, turns out there's another contributor to its longevity, and that is the soil beneath it.

Joining me to talk about that and other selected short subjects in science is Sophie Bushwick, senior editor at Popular Science. Welcome

to Science Friday. Thank you. I have to note that congratulations are in order because the

Popside team was victorious at our sci-fri trivia night earlier this week. It was a tough battle. We were

really excited to win. Two years in a row. Two years in a row. Consecret. Wow. We'll have to see what happens next year. We'll aim for a three-peat. Three p. All right, let's talk about the news. What's this leaning tower of Pisa story? What's the secret here? Right. So the leaning tower of Pisa, one of the reasons it's leaning is because the soil in the region is very soft. In fact, there's a couple other towers that are also leaning, although not as much.

Pisa, that tower is leaning at about a four-degree angle right now, and at its greatest,

it was at closer to a five-and-a-half-degree angle.

So you would think that this really unstable tower would be really in bad shape when earthquakes strike,

and at least four

major earthquakes have hit the area since the construction of the tower, but it's withstood them.

So this latest study looked at the relationship between the soil and the tower, and they found

that one of the reasons it's been able to withstand the earthquakes is because interaction between

that soft soil, the same soil that makes it lean,

and this tall, rigid tower has sort of balanced out, and so it doesn't vibrate when the ground

vibrates the same way other buildings do.

So the soil is sort of squishy and absorbs the vibration.

It has to do with the interaction between that squishy soil and the tower itself.

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