It's Monday, May 21st, 2018, and you're listening to Inquiring Minds.

I'm Indra Viscontas.

And I'm Kishorehari.

Each week we bring you a new in-depth exploration of the space where science, politics, and society collide.

We endeavor to find out what's true, what's left to discover, and why it all matters.

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What's your favorite planet?

I'm a Mars guy.

You're a Mars guy.

Do you think Pluto is a planet?

No, it's definitely not a planet.

I thought we settled this a long time ago.

Why are we still arguing about this?

Well, because I recently spoke to an astrobiologist and the principal investigator of the New Horizons mission to Pluto, and they certainly call it a planet. Well, I mean, it's a dwarf planet.

So, yeah, that was the one thing that kind of surprised me, too, when I was reading their book. So they have written a book about this mission to Pluto, the first time that we got pictures back from Pluto. Do you remember this when this happened?

I totally remember this. New Horizons was super exciting. I actually was at my computer waiting to see some of the first images released. And then when the heart image

showed up a few days later, it's basically like nitrogen ice, right? In this sort of heart

shape when you'd sort of tilt the dwarf planet at a certain angle. I thought that was delightful.

Yeah. So I think a lot of people, like you were really captivated

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