Wolf-Rayet 124: A prelude of Supernova

The luminous, hot star Wolf-Rayet 124 (WR 124) is prominent at the center of the James Webb Space Telescope’s composite image combining near-infrared and mid-infrared wavelengths of light, reported NASA.

The star displays the characteristic diffraction spikes of Webb’s Near-Infrared Camera (NIRCam), caused by the physical structure of the telescope itself.

NIRCam effectively balances the brightness of the star with the fainter gas and dust surrounding it, while Webb’s Mid-Infrared Instrument (MIRI) reveals the nebula’s structure, reported NASA. 

Background stars and background galaxies populate the field of view and peek through the nebula of gas and dust that has been ejected from the aging massive star to span 10 light-years across space.

A history of the star’s past episodes of mass can be read in the nebula’s structure. Rather than smooth shells, the nebula is formed from random, asymmetric ejections, reports NASA.

Bright clumps of gas and dust appear like tadpoles swimming toward the star, with tails streaming out behind them, blown back by the stellar wind. 

Wolf-Rayet stars are a rare prelude to the famous final act of massive stars: the supernova. In one of its first observations, NASA’s James Webb Space Telescope captured the Wolf-Rayet star WR 124 in unprecedented detail.

A distinctive halo of gas and dust frames the star and glows in the infrared light detected by Webb, displaying knotty structure and a history of episodic ejections. Despite being the scene of an impending stellar “death,” astronomers also look to Wolf-Rayet stars for insight into new beginnings, reports NASA.

Cosmic dust is forming in the turbulent nebulas surrounding these types of stars, which is composed of the heavy-element building blocks of the modern universe, including life on Earth.  

Webb is an international program led by NASA with its partners, ESA (European Space Agency), and CSA (Canadian Space Agency).