<I>C. elegans</i> Roundworm (IMAGE) NASA/Johnson Space Center Caption Caenorhabditis elegans -- a millimeter-long roundworm with a genetic makeup scientists understand -- is central to a pair of Japan Aerospace Exploration Agency investigations into muscle and bone loss of astronauts on the International Space Station. Credit NASA 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.