Spectrum (IMAGE) Penn State Caption A planet's atmosphere absorbs specific wavelengths of the star's light that reveal the atmosphere's chemical composition. Credit NASA, ESA, and A. Feild (STScI) Usage Restrictions Non commercial use only 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.