SPARKLING SKY
Although we think of diamonds as being very rare, the conditions which produce them occur quite widely throughout the universe. As a result, there really are ‘diamonds in the sky’. We have direct evidence of this in the form of diamond-containing meteorites, which originated very early in the history of the Solar System.
Fast-forwarding to the present day, Earth isn’t the only planet in the Solar System where diamonds can be found. Deep inside the atmospheres of the ice giants Neptune and Uranus, carbon can be compressed to the extreme pressures and temperatures needed to form diamonds. These then sink down to the planetary cores in the form of a spectacular ‘diamond rain’.
Looking beyond the Solar System, it may be possible to find planets with many more diamonds than Earth. It’s conjectured that planets orbiting carbon-rich stars would have a much higher diamond content than our own planet. A few years ago there was a flurry of excitement around one particular exoplanet, 55 Cancri e, which was hailed as the ‘diamond planet’ because it was believed to be especially rich in diamonds. However, while that theory hasn’t been completely disproved, it seems much less likely now.