Scientists used the James Webb Space Telescope to image Messier 82, also known as the Cigar Galaxy. A new composite image of Messier 82 includes data from the James Webb Space Telescope and the Hubble Space Telescope, depicting approximately 16.5 million resolved stars.

The imaging survey of Messier 82 involved 65 hours of observation time with the Webb telescope's Near-Infrared Camera (NIRCam) instrument. Messier 82 is an edge-on spiral galaxy undergoing rapid star formation, located 12 million light-years away, and its star-forming rate is 10 times faster than that of the Milky Way galaxy.

Messier 82 ejects bipolar plumes of material above and below its disk, which have an hourglass shape. The galaxy's intense star formation is estimated to last a few hundred million years and is thought to be the result of a galaxy merger. In the composite image, stars appear blue-white, while dust grains are red-orange, and ionized hydrogen gas is yellow. Yellow tendrils of material closest to Messier 82's disk represent ionized gas, while orange material farther away depicts small polycyclic aromatic hydrocarbon dust grains.

Adam Smercina, a NASA Hubble Fellow at the Space Telescope Science Institute and incoming Assistant Professor at Tufts University, is the principal investigator of the Messier 82 study. "M82 is a mess, but it's a beautiful mess. We don't fully understand what's going on, especially concerning its evolutionary history. What could have triggered such an elevated rate of star formation? How long has this galaxy been driving plumes of material away from its center?" Smercina said.

Benjamin Williams, a team member from the University of Washington, said, "The sheer number of stars that we were able to resolve with Webb is incredible. It's a whole different world from what we've been able to see with other telescopes. All of these stars collectively provide a detailed fossil record of the formation and evolution of M82." Eric Bell, a team member from the University of Michigan, said, "At first glance, the disk of the galaxy may seem less spectacular because Webb sees through the dust. But M82 is a delightfully complex system. Webb's observations will help us address some ongoing mysteries, such as how star formation has moved within M82 over the last few billion years."