A Deep Look at Whirlpool Galaxy M51a (image) Case Western Reserve University Share Print E-Mail Caption Case Western Reserve University astronomers found new features on the first-known spiral galaxy, M51a, which has been sketched and photographed for 170 years. Credit Aaron Watkins Usage Restrictions Please give proper credit. 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.