Gas Motion (IMAGE) National Institutes of Natural Sciences Caption The three gaseous components form the long-theorized 'donut' structure: (1) a disk of infalling dense cold molecular gas, (2) outflowing hot atomic gas, and (3) gas returning to the disk. Credit NAOJ 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.