Rare Wolf–Rayet Supernova Captured by James Webb Space Telescope

By Pranav Mahapatra

March 15, 2023
wolf rayet star wr-124 supernova infrared capture by james webb space Telescope
The WR 124 Supernova captured by JWST (NIRCam and MIRI composite image). Credits: NASA/ESA/CSA

The James Webb Space Telescope has recently captured striking images of the supernova of a rare star “WR 124”, as one of its first observations in 2022[1].

WR 124 falls under the Wolf–Rayet Stars (WR Stars) category; which is a rare heterogeneous set of stars with unusual spectra showing distinguished broad emission lines of ionized helium and highly ionized nitrogen or carbon.

These JWST observations are very valuable for astronomers as only a few stars become Wolf–Rayets during their life cycle, before becoming a supernova; that’s what makes them rare.

The surface temperatures of known Wolf–Rayet stars are estimated to range from 20,000 – 210,000 Kelvins; that’s hotter than almost all other kinds of stars.

The JWST has already been making people fall in love with distinguished images of the universe and this new capture opens up new possibilities for astronomers.

Qualities of the Wolf–Rayet Captured by JWST

JWST captured the incoming infrared light from the WR 124 which is among the most luminous, most massive, and most briefly-detectable stars known.

The star is surrounded by a halo of gas and dust, with intricate structures that depict the qualities and ejections during the supernova.

The cosmic dust around is stated to be forming nebulae composed of heavy elements which aren’t naturally found on planets including Earth, but only formed during such supernova events and delivered throughout the universe.

Wolf-Rayet 124 (MIRI image)

WR 124 is about 30 times the mass of the Sun and has already ejected out about 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 the James Webb Space Telescope.

Astronomers are particularly interested in studying the cosmic dust which could survive a supernova through these observations as the dust leads to nebulae which often serve as stellar nurseries.

These stellar nurseries are where new stars and planetary formations take place and these regions are also home to heavy elements that form only during such events.

JWST’s Wolf Rayet Capture Opens Up New Possibilities for Astronomers

ESA quotes, “Despite the many essential roles that dust plays, there is still more dust in the Universe than astronomers’ current dust-formation theories can explain. The Universe is operating with a dust budget surplus.”

JWST’s distinguished capture and observations of such a rare event opens up new possibilities for astronomers to better understand our Universe by evincing the mysteries of cosmic dust during such events.

Before the Webb telescope, astronomers did not have sufficient information to probe and understand the bewildering questions of dust production in environments like WR 124.

Through the JWST’s unprecedented observations, questions like whether that dust was of sufficient size and quantity to survive and make a significant contribution to the overall dust budget can be investigated with real data.


  1. European Space Agency, ‘Webb captures rarely seen prelude to a supernova‘, 14 March 2023[]