NASA’s James Webb Space Telescope has discovered new details of Supernova 1987A using the NIRCam (Near Infrared Camera) instrument. Structures, some of which can only be seen in the infrared, provide clues about the evolution of supernovae over time.

Webb’s NIRCam (Near Infrared Camera) captured this detailed image of SN 1987A (supernova 1987A) with annotations to highlight key structures. In the center, material from the supernova forms a keyhole shape. To his left and right are Webb’s newly discovered pale crescents. Behind them, the equatorial ring of material ejected tens of thousands of years before the supernova explosion contains bright hot spots. Outside is diffuse radiation and two weak outer rings. In this image, blue is light 1.5 microns (F150W), cyan 1.64 and 2.0 microns (F164N, F200W), yellow 3.23 microns (F323N), orange 4.05 microns (F405N), and red 4.44 represents micron (F444W).

NASA’s James Webb Space Telescope has begun studying one of the most famous supernovae, SN 1987A (Supernova 1987A). Located 168,000 light-years away in the Large Magellanic Cloud, SN 1987A has been the subject of intense observations in wavelengths from gamma rays to radio waves for nearly 40 years since its discovery in February 1987. Webb’s new NIRCam (Near Infrared Camera) observations provide an important clue to our understanding of how a supernova evolves over time to form its remnant.

Main features of observation

This image shows the central structure as a keyhole. This center is filled with gas and dust released during the supernova explosion. The dust is so dense that even the near-infrared light Webb detected cannot pass through the dust, creating a dark “hole” in the keyhole.

Taken by the Hubble Space Telescope’s Wide Field Planetary Camera 2 and Advanced Survey Camera, this time-lapse sequence of images shows changes in the ring of matter surrounding the stellar explosion, called Supernova 1987A. This spectacular light show is the collision of debris with the gas ring surrounding the explosion site, as seen from September 24, 1994 to November 28, 2003. Image source: NASA and L. Barranger (STScI); Image: NASA, P. Challis, R. Kirchner (Harvard-Smithsonian CfA), B. Sugerman (STScI)

A bright equatorial ring surrounds the inner keyhole, forming a band around the waist that connects the two pale arms of the outer hourglass-shaped rings. Composed of material ejected tens of thousands of years before the supernova explosion, the equatorial ring contains bright hot spots that were created when the supernova shock wave hit the ring (see video above). Now spots can be detected even from outside the ring with scattered radiation around it. These are regions of supernova impacts that come into contact with the outer material.

Comparative ideas and new discoveries

Although these structures have been observed to varying degrees by NASA’s Hubble and Spitzer Space Telescopes and the Chandra X-ray Observatory, Webb’s unique sensitivity and spatial resolution revealed a new feature of this supernova remnant: small, crescent-like structures. These crescents are thought to be part of the outer layers of gas released from the supernova explosion. Their luminosity can indicate limb illumination, an optical phenomenon caused by three-dimensional imaging of expanding material. So our point of view gives the impression that there is more material in these two crescents than there actually is. Source