# RCW 120

Composite image of the nebula RCW 120. The ring-shaped clouds around the nebula were detected by the Spitzer Space Telescope. SOFIA measured the glowing gas shown in red and blue to study the nebula’s expansion speed and determine its age. The blue gas represents gas expanding in the direction toward Earth and the red away from Earth. The expansion is triggering the birth of stellar neighbors at breakneck speeds – and revealing the nebula is younger than previously believed. Credit: NASA/JPL-Caltech/SOFIA