JWST has made several unexpected discoveries concerning galaxies at high redshift. One of the most recent discoveries relates to GN-z11, a luminous galaxy at redshift 10.6. This galaxy is observed to have super-solar nitrogen abundances, which cannot be explained by normal enrichment mechanisms. Chris Nagele and Hideyuki Umeda, from the University of Tokyo, have run simulations which suggest this nitrogen could have come from a supermassive star, which is a star with mass greater than ten thousand times the mass of our sun. They found that the nitrogen can originate from stellar winds or a thermonuclear explosion.

• Introduced in AAS nova (31 May 2023)
• The paper in ApJ Letters