The James Webb Space Telescope (JWST) has unveiled a stunning image of SN1987A, a dying star that went supernova in 1987. This event, the closest and brightest star explosion visible from Earth, was captured by JWST, revealing the star’s appearance resembling a necklace surrounded by gas and dust, including two previously undetected pearls, which were missed by the European Hubble Space Telescope.
This new discovery, located 170,000 light-years away, allows astronomers to delve deep into the life cycles and demise of stars. This supernova, situated in the Southern hemisphere of the sky, stands as the most extensively observed celestial object in space. The image portrays a series of luminous rings representing layers of gas and dust expelled by SN1987A during its various stages of death, triggered by the expanding shockwaves from its final moments of collapse and supernova explosion.
Scientists reveal that one of these rings resembles a string of pearls, composed of material ejected approximately 20,000 years before the supernova event. The James Webb Space Telescope provided the clearest view to date of the necklace and the surrounding diffuse brightness.
Dr. Roger Wesson from Cardiff University, UK, stated, “We’re now able to observe new hotspots emerging outside the previously illuminated ring. Additionally, we detect emissions from molecular hydrogen within the ring, an unexpected finding that only JWST’s superior sensitivity and resolution could reveal.”
Newly discovered features, such as crescent-shaped or arc-like emissions within the cosmic necklace, appear just outside the dense inner region, resembling a keyhole. Dr. Mikako Matsuura, the lead analyst, commented, “We have yet to fully understand these crescents. It’s possible that this material is being illuminated by a reverse shock, one that is moving back toward the keyhole.”
Despite its capabilities, JWST cannot visualize the remnants of the dying star buried within the dense dust field. These remnants are believed to be compact objects composed of neutron particles, measuring only a few tens of kilometers in size.
Since the star’s supernova event, every significant telescope capable of observing SN1987A has closely studied its evolution and characteristics. Astronomers speculate that the star was a relatively young, hot star, approximately 20 to 30 times the mass of our Sun. Dr. Wesson added, “One of the mysteries of this star is that it exploded as a blue supergiant, contrary to prevailing theories that only red supergiant stars could explode. Unraveling this mystery has been a significant pursuit.”
Moreover, there are indications that JWST will remain operational for a longer period than initially anticipated, potentially up to 20 years, providing a powerful tool for ongoing monitoring of SN1987A and its evolving dynamics.