Diamond Rain Graphic (IMAGE) DOE/SLAC National Accelerator Laboratory Caption A cutaway shows the interior of Neptune (left). In an experiment conducted at the Linac Coherent Light Source, the team studied a plastic simulating compounds formed from methane -- a molecule with just one carbon bound to four hydrogen atoms that causes the distinct blue cast of Neptune. Methane forms hydrocarbon (hydrogen and carbon) chains that respond to high pressure and temperature to form "diamond rain" in the interiors of icy giant planets like Neptune. The scientists were able to recreate similar conditions using high-powered optical lasers and watch the small diamonds form in real-time with X-rays. Credit Greg Stewart/SLAC National Accelerator Laboratory Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.