Electromagnetic spectrum (IMAGE) NASA/Goddard Space Flight Center Caption This electromagnetic spectrum shows how energy travels in waves; Humans can only see visible light, but the entire spectrum is used by NASA instruments to observe Earth and more. 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.