Imagine it's December 31st, New Year's Eve, normally a time of joy and celebration, but this is

1943 in Nazi- occupied France.

It's near midnight, just off the northern coast.

It's moonless out and dark.

The wind is whipping around.

Nazi machine guns loom on the bluffs overlooking the beach.

Suddenly though, two lone figures emerge from the icy water.

They're exhausted from swimming in, but they don't rest. They immediately get to work.

They take depth readings in the water.

Then they examine the beach.

They rub the soil and sand between their fingers and slip samples into baggies to take home, if they get home.

At any moment, huge Cleaglites could expose them and send a hellfire of bullets tearing into their bodies.

So who was this daring duo? Intrepid spies? Special Ops Commandos?

Nope. They were geologists.

Rock nerds, who had spent far more hours chipping stones than shooting guns.

As for what on-Earth geologists were doing invading Nazi France?

Well, the answer is simple.

They were doing geology.

They were on a special mission to scout the beaches of France

in preparation for June 6th, 1944. D-Day.

This summer marks the 80th anniversary of that invasion.

And while you've probably never given much thought to the science of D-Day,

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