Wolf-Rayet 124 (MIRI image)

Wolf-Rayet stars are known to be efficient dust producers, and the Mid-Infrared Instrument (MIRI) on the NASA/ESA/CSA James Webb Space Telescope shows this to great effect. Cooler cosmic dust glows at the longer mid-infrared wavelengths, displaying the structure of WR 124’s nebula. The 10 light-years-wide nebula is made of material cast off from the ageing star in random ejections, and from dust produced in the ensuing turbulence. This brilliant stage of mass loss precedes the star’s eventual supernova, when nuclear fusion in its core stops and the pressure of gravity causes it to collapse in on itself, and then explode. As MIRI demonstrates here, Webb will help astronomers to explore questions that were previously only available to theory, questions like how much dust stars like this create before exploding in a supernova, and how much of that dust is large enough to survive the blast and go on to serve as a building block of future stars and planets.

In this image red is assigned to wavelengths of 12.8 and 18 microns (F1280W, F1800W), green to 11.3 microns (F1130W), and blue to 7.7 microns (F770W).

[Image Description: A large, bright cloud of yellow, pink, and purple surrounds a white star that looks like a tiny snowflake. A few small blue background stars are visible. Dark gaps break up the cloud, and small bright areas on the upper and lower left appear like schools of tadpoles swimming toward the central star. There are areas where clumps of bright hot material are being blown outward by the star, like hair streaming out behind someone standing in front of a fan.]