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NASA’s James Webb Space Telescope has begun studying one of the most famous supernovae, SN 1 A (Supernova 1 A). Located 168,000 light-years away in the Large Magellanic Cloud, SN 1 A has been the subject of intense radio and gamma-ray observations for nearly 40 years since its discovery in February 1 . New near-infrared observations from Webb’s NIRCam provide important clues for understanding how a supernova evolves and shapes its remnant over time.
This image shows a central keyhole-shaped structure. This center is filled with condensed gases and dust expelled by the supernova explosion.The dust is so dense that even the near-infrared light discovered by Webb cannot penetrate it, creating a dark “hole.” in the keyhole. A brilliant equator ring surrounds the inner lock, forming a belt connecting the two faint arms of the hourglass-shaped outer rings.
The equatorial ring is made of material ejected tens of thousands of years before the supernova exploded. It contains bright, hot spots formed when the supernova shock wave hit the ring. Now the spots can also be found outside the ring and surround it with a diffuse emission. These are the places where supernova shocks hit most external materials.
Although these structures have been observed to varying degrees by the Hubble and Spitzer Space Telescopes and the Chandra X-ray Observatory, Webb’s unprecedented sensitivity and spatial resolution has revealed a new feature of supernova remnants: small, crescent-shaped structures. These crescents are thought to be part of the outer layers of gas released by the supernova explosion.
Their brightness may indicate thinning limbs, an optical phenomenon created by viewing material expanding in three dimensions. In other words, from our vantage point, it appears that there is more material in these two crescents than is actually there.
The high resolution of these photos is also remarkable.Before Webb, the now-defunct Spitzer Telescope observed this supernova in the infrared throughout its lifetime, providing important data on how its performance changed over time. However, he has never been able to observe a supernova so clearly and in such detail.
Despite the decades of study since the supernova’s initial discovery, there are several mysteries that remain, particularly surrounding the neutron star that should have been formed in the aftermath of the supernova explosion. Like Spitzer, Webb will continue to observe the supernova over time.
Its NIRSpec (Near-Infrared Spectrograph) and MIRI (Mid-Infrared Instrument) instruments will offer astronomers the ability to capture new, high-fidelity infrared data over time and gain new insights into the newly identified crescent structures. Further, Webb will continue to collaborate with Hubble, Chandra, and other observatories to provide new insights into the past and future of this legendary supernova.
Provided by NASA
