These side-by-side images (click for a closer look) show the spiral galaxy Messier 100 in two views: the image on the right is taken with the Very Large Telescope in optical bands, and the image on the left is an infrared view captured by the Spitzer space telescope. In a new study led by Bruce Elmegreen (IBM Research Division, T.J. Watson Research Center), a team of scientists has further analyzed Spitzer’s observations of M100. The authors focus on the regularly spaced infrared-bright, star-forming clumps that lie along the dusty filaments — which, while clearly visible in infrared, often can’t be seen in the optical. The regularity of the spacing and size of these clumps suggest that star formation within the spiral arms of M100 occurs as a result of gravitational instabilities in gas that was accumulated by spiral density waves moving through the galaxy. For more information, check out the original article below.
Citation
“Regularly Spaced Infrared Peaks in the Dusty Spirals of Messier 100,” Bruce G. Elmegreen et al 2018 ApJ 863 59. doi:10.3847/1538-4357/aacf9a