Astronomers used the NASA/ESA/CSA James Webb Space Telescope to look toward M82’s centre, where a galactic wind is being launched as a result of rapid star formation and subsequent supernovae. Studying the galactic wind can offer insight into how the loss of gas shapes the future growth of the galaxy.
This image from Webb’s NIRCam (Near-Infrared Camera) instrument shows M82’s galactic wind via emission from sooty chemical molecules known as 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 resembles that of hot, ionised gas, suggesting PAHs may be replenished by continued ionisation of molecular gas.
In this image, light at 3.35 microns is coloured red, 2.50 microns is green, and 1.64 microns is blue (filters F335M, F250M, and F164N, respectively).
[Image description: 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 white points in various sizes – stars or star clusters – are scattered throughout the image, but are most heavily concentrated toward the centre. Many clumpy, red filaments extend vertically above and below the plane of the galaxy.]