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Diamonds in the night sky could be real diamonds

Experiments by researchers at the University of California, Berkeley, suggest there may well be diamonds hailing down through the gaseous atmospheres of Neptune and Uranus.

In the latest issue of Science, the team, led by Laura Benedetti, a graduate student in physics, and Raymond Jeanloz, Professor of Geology and Geophysics, report experiments which copy the conditions on these planets showing that methane in the planet's atmosphere can turn into diamond at the high temperatures and pressures found inside the planets.

Neptune "Once these diamonds form, they fall like raindrops or hailstones toward the center of the planet," said Benedetti.

The team reproduced these conditions inside a diamond anvil cell, squeezing liquid methane to several hundred thousand times atmospheric pressure. When they focused a laser beam on the pressurized liquid, heating it to some 2760 degrees Celsius, diamond dust appeared. The high temperature breaks up methane (CH4) into carbon and hydrogen, while high pressure condenses the carbon to diamond.


"This is opening the door to study of the interesting types of chemical reactions taking place inside planets," Jeanloz said. "It is not amazing that chemistry like this happens inside planets it's just that most people haven't dealt with the chemical reactions that can occur," Benedetti said. "The interior of these planets may be much more complicated that our current picture."


Jeanloz and his team are planning experiments with other planetary elements, like ammonia and water, to see what happens at high temperatures and pressures.

Tags: astronomy-space, physics