Is it possible to drill a hole straight through a planet?

It is the mission of children on beaches around the world: to dig through the centre of the planet and come out the other side. But such an endeavour is far from simple. Earth isn’t just sand and rocks all the way through – it holds a sea of molten iron, and the temperature and pressure near the middle would be enough to melt any ambitious digger, along with any tools they might use to make their hole.

In the second episode of the Dead Planets Society podcast, our intrepid hosts Leah Crane and Chelsea Whyte dig into the question of what might happen if we were to bore a hole through a planet. Gas giants are probably a no-go, because the temperatures and pressures below their clouds are too intense for any material humans have ever made to stay intact, let alone for actual humans to survive.

For an indestructible vessel, though, the journey would be interesting, with strange gravitational effects and phases of matter we have never seen before. Maybe on a smaller world, like Pluto, you wouldn’t need an indestructible vessel – in fact, Pluto’s surface is so cold that a person’s body heat would be enough to start a borehole. Planetary scientists Konstantin Batygin and Baptiste Journaux join our hosts this week to talk about the logistics of drilling through an entire world, and what would happen if we could actually pull that off.

Dead Planets Society is a podcast that takes outlandish ideas about how to tinker with the cosmos – from unifying the asteroid belt to destroying the sun – and subjects them to the laws of physics to see how they fare.

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