The remnants of a star that exploded 36 years ago has fallen under the gaze of the James Webb Space Telescope (JWST) — and this observatory’s Near Infrared Camera (NIRCam) has captured the expanding stellar debris with unprecedented resolution, revealing entirely new details about this burgeoning debris. supernova remnants.
The closest supernova observed since Kepler’s supernova lit up the Milky Way in 1604, this stellar explosion was first identified in 1987 and is known as Supernova 1987A.
It lies about 168,000 light-years from Earth in the Large Magellanic Cloud and marks the destruction of a blue giant star called Sanduleak-69 202. Before it exploded, this star was thought to have a mass of about 20 times that of the Sun.
In fact, this supernova was so bright it was visible to the naked eye in the Southern Hemisphere, and astronomers have been tracking its expanding debris ever since. Now, the James Webb Space Telescope has been used to impact the supernova remnant in a study led by Mikako Matsuura of Cardiff University in the UK, resulting in this stunning image of the aftermath of a dead star.
The Matsuura Project used the James Webb Space Telescope to measure the supernova’s expanding shock wave as that wave interacted with surrounding material. When massive stars, such as blue giant stars, approach the end of their lives, they become unstable and begin to shed large amounts of matter. The Hubble Space Telescope previously watched the expanding shock wave of supernova 1987A, which initially was moving at about 7,000 kilometers per second (4,350 miles per second), collided with a ring of oceanic debris ejected by the doomed star 20,000 years or so before it became a supernova. greatest. When the wave hit this ring, it slowed to about 2,300 kilometers per second (1,430 miles per second).
The blocks inside this ring sparkle gradually, revealing a pearl bracelet. The other two rings, which appear to be on a different plane from the main ring and are thinner and fainter, are more obscure; Astronomers have speculated that these rings could be where stellar winds emitted prior to the supernova interact with material previously ejected by the star.
Alternatively, it could be lit by jets from an invisible neutron star that experts believe must have formed along with the supernova explosion. The James Webb Space Telescope has revealed new details on this front, showing that the shock wave expanded beyond the main ring and accelerated again to about 3,600 kilometers per second (2,236 miles per second) while producing new hotspots that may over time become bright. Such hot spots. previously identified.
More diffuse emissions are also seen as a general flare, as the blast wave from the supernova stirs up the gas around the site of the explosion. In addition, the James Webb Space Telescope has spotted something new: Within the main ring, where gas and dust form an ejected keyhole-shaped cloud, there are two tantalizing arcs, or crescents. The team suggests that these features could represent the outer layers of gas produced by the supernova, as we view this part at an angle.
The James Webb Space Telescope will continue to monitor the expanding supernova remnant as it evolves, as well as search for the neutron star at the center of the explosion, which has not yet been seen.
However, there is indirect evidence for the neutron star’s existence in the form of X-ray emission detected by NASA’s Chandra and NeuSTAR X-ray observatories, as well as observations of the Atacama Large Millimeter/Submillimeter Array (ALMA) pointing towards the neutron star. It could be hidden inside one of the lumps of dust in the heart of the rest.