The starburst galaxy M82 was observed by the NASA/ESA Hubble Space Telescope in 2006, which showed the galaxy’s edge-on spiral disc, shredded clouds, and hot hydrogen gas. The NASA/ESA/CSA James Webb Space Telescope has observed M82’s core, capturing in unprecedented detail the structure of the galactic wind and characterising individual stars and star clusters.
The Webb image is from the telescope’s NIRCam (Near-Infrared Camera) instrument. The red filaments trace the shape of the cool component of the galactic wind via polycyclic aromatic hydrocarbons (PAHs). PAHs are very small dust grains that survive in cooler temperatures but are destroyed in hot conditions. The structure of the emission is similar to that of the ionised gas, suggesting PAHs may be replenished from cooler molecular material as it is ionised.
[Image description: Left: Messier 82 as imaged by Hubble. Hour-glass-shaped red plumes of gas are shooting outward from above and below a bright blue, disc-shaped centre of a galaxy. This galaxy is surrounded by many white stars and set against the black background of space. Right: A section of Messier 82 as imaged by Webb. An edge-on spiral starburst galaxy with a bright white, glowing core set against the black background of space. A white band of the edge-on disc extends from lower left to upper right. Dark brown tendrils of dust are scattered thinly along this band. Many clumpy, red filaments extend vertically above and below the plane of the galaxy.]