Presolar Grain with Nebula (IMAGE) Field Museum Caption Dust-rich outflows of evolved stars similar to the pictured Egg Nebula are plausible sources of the large presolar silicon carbide grains found in meteorites like Murchison. Credit Image courtesy NASA, W. Sparks (STScI) and R. Sahai (JPL). Inset: SiC grain with ~8 micrometers in its longest dimension. Inset image courtesy of Janaína N. Ávila. Usage Restrictions Please include credit 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.