FIVE THINGS ABOUT SPACE GEMS

1 A HAIL OF GEMS

Consider this your daily reminder that the solar system is even more awesomely bonkers than you realized: On Uranus and Neptune, scientists forecast rain storms of solid diamonds.

2 UNDER PRESSURE

The gems form in the hydrocarbon-rich oceans of slush that swath the gas giants’ solid cores. Scientists have long speculated that the extreme pressures in this region might split those molecules into atoms of hydrogen and carbon, the latter of which then crystallize to form diamonds. These diamonds were thought to sink like rain through the ocean until they hit the solid core. But no one could prove that this would really work — until now.

3 EXPERIMENTS

In a study published in the journal Nature Astrophysics, researchers say they were able to produce this “diamond rain” using fancy plastic and high-powered lasers. “Previously, researchers could only assume that the diamonds had formed,” lead author Dominik Kraus, a physicist at the Helmholtz Dresden-Rossendorf research centre in Germany, told the magazine Cosmos. “When I saw the results of this latest experiment, it was one of the best moments of my scientific career.”

4 PREVIOUS ATTEMPTS

Scientists have tried to do this before — but they ran into problems mimicking the incredible pressures near the gas planet’s cores. Neptune and Uranus are 17 and 15 times the mass of Earth, respectively, and their oceans are crushed by pressures millions of times more intense than the air pressure at Earth’s sea level. To match this absurd intensity, Kraus and his colleagues used two types of laser — one optical, one X-ray — to produce shock waves. These waves were then driven through a block of polystyrene — a type of plastic composed of hydrogen and carbon, just like Uranus and Neptune’s oceans. “The first smaller, slower wave is overtaken by another stronger second wave,” Kraus explained in a news release.

5 IT WAS ALL OVER IN A FLASH

The process lasted only a fraction of a second, and the diamonds were no bigger than a nanometre in length. But Kraus and his colleagues believe that the diamonds that develop on Uranus and Neptune are probably bigger and longer-lasting.