So if we were standing at the South Pole, maybe on the rim of a crater or some other peak,

I think the first thing we would notice is the sun is not just going nicely overhead.

It is kind of circling the horizon.

Maybe occasionally it dips below or behind a peak,

but it's always going to be this pretty extreme lighting.

This is Brett De Nevy.

She's a planetary geologist,

and she's based at the Applied Physics Lab

at Johns Hopkins University.

And so that means some of the areas like these peaks, you're going to be in sunlight

for a lot of the time. And then if you look down into maybe Shackleton Crater right near the

South Pole, it's going to be dark. And it will have been dark for potentially billions of years

because the sunlight is never going to make it down in there.

As you may have figured out, we're not talking about our earthly South Pole in Antarctica.

We're talking about a South Pole almost a quarter of a million miles away, the one on the moon.

As we orbit the Sun, the South Pole here on Earth sees nothing but darkness for half the year.

And then the other half is nothing but daylight.

That's because our planet is tilted on its axis.

But the Moon orbits Earth almost straight up and down.

And that causes this bizarre lighting at the moon's South Pole. You'd see mountain peaks

illuminated by an almost perpetual sunset glow and craters freezing in permanent shadow.

And so that's kind of the key defining, like environmental feature of the South Pole,

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