X-ray and Infrared Image of RCW 120 (IMAGE) Harvard-Smithsonian Center for Astrophysics Caption RCW 120 is another star-forming region that was part of the new research. It is slightly farther away than the Lagoon Nebula at a distance of about 5,500 light years. This view of RCW 120, which has the same wavelengths and colors as the Lagoon composite, contains an expanding bubble of hydrogen gas, about 13 light years across. This structure may be sweeping up material into a dense shell and triggering the formation of stars. Credit X-ray: NASA/CXC/Penn State/K. Getman, et al; Infrared: NASA/JPL/Spitzer 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.