File:NASA’s Webb Telescope Captures Rarely Seen Prelude to Supernova (MIRI Image) (52748025943).png

Sakura to Supernova

This rare sight is a super-bright, massive Wolf-Rayet star. Calling forth the ephemeral nature of cherry blossoms, the Wolf-Rayet phase is a fleeting stage that only some stars go through soon before they explode.

The star, WR 124, is 15,000 light-years away in the constellation Sagittarius. It is 30 times the mass of the Sun and has shed 10 Suns worth of material – so far. As the ejected gas moves away from the star and cools, cosmic dust forms and glows in the infrared light detectable by Webb.

The origin of cosmic dust that can survive a supernova blast is of great interest to astronomers for multiple reasons. Dust shelters forming stars, gathers together to help form planets, and serves as a platform for molecules to form and clump together, including the building blocks of life on Earth.

Stars like WR 124 also help astronomers understand the early history of the universe. Similar dying stars first seeded the young universe with heavy elements forged in their cores – elements that are now common in the current era, including on Earth.

The James Webb Space Telescope opens up new possibilities for studying details in cosmic dust, which is best observed in infrared wavelengths of light. Webb’s Near-Infrared Camera (NIRCam) balances the brightness of WR 124’s stellar core and the knotty details in the fainter surrounding gas. The telescope’s Mid-Infrared Instrument (MIRI) reveals the clumpy structure of the gas and dust nebula of the ejected material now surrounding the star.

Read more: <a href="https://www.nasa.gov/feature/goddard/2023/nasa-s-webb-telescope-captures-rarely-seen-prelude-to-supernova/" rel="noreferrer nofollow">www.nasa.gov/feature/goddard/2023/nasa-s-webb-telescope-c...</a>

Image description: A faint snowflake-like star shines in white at the center of this image. A clumpy cloud of material surrounds this central star, with more material above and below than on the sides, in some places allowing background stars to peek through. The cloud material is a dark yellow/brown closer to the star, and turns a pinkish purple at its outer edges. Combined together, the central star and its cloud resemble the delicate petals of a cherry blossom. The black background features many smaller white stars scattered throughout.

This image: Wolf-Rayet stars are known to be efficient dust producers, and the Mid-Infrared Instrument (MIRI) on NASA’s 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 aging 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 left to theory – about 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 building blocks of future stars, planets, and complex molecules.

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).