AIRS Image of 31W (image) NASA/Goddard Space Flight Center Share Print E-Mail Caption The AIRS instrument aboard NASA's Aqua satellite captured an infrared image of Tropical Depression 31W on Nov. 17 at 12:17 a.m. EST (0517 UTC). Coldest cloud tops and strongest storms appear in purple. Credit Credits: NASA JPL/Ed Olsen Usage Restrictions None Share Print E-Mail 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.