Fig 1 (IMAGE) Stockholm University Caption Fig. 1. Combination of a Hubble image of SN 1987A and the compact highly ionized argon source in Fig. 2. The faint blue source in the centre was detected by the NIRSpec instrument on JWST. Outside of this is the rest of the supernova, which contains the most mass and is expanding at thousands of kilometers every second. The inner bright "string of pearls" is gas from the star's outer layers that was ejected about 20,000 years before the explosion. The collision between the rapidly expanding supernova remnant and the ring gives rise to the heated clumps in the ring. Outside the inner ring are two outer rings, which probably arose at the same time as the inner ring was formed. The bright stars to the left and right of the inner ring are unrelated to the supernova. (Illustration: HST, JWST/NIRSpec, J. Larsson) Credit Illustration: HST, JWST/NIRSpec, J. Larsson Usage Restrictions None License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.