Vapor tracer ampule doors are open (IMAGE) NASA/Goddard Space Flight Center Caption The vapor tracer ampule doors are open on the CREX-2 payload during testing at the Andøya Space Center. Credit Credits: NASA Usage Restrictions No restrictions. License Public Domain 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.