A Planetary Nebula from a 5.7 M⊙ Progenitor in a 90 Myr M31 Star Cluster: https://iopscience.iop.org/article/10.3847/2041-8213/ae77e4 -> Extragalactic #PlanetaryNebula with Massive Progenitor Sheds Light on Stellar Evolution: https://aasnova.org/2026/09/16/extragalactic-planetary-nebula-with-massive-progenitor-sheds-light-on-stellar-evolution/
![Color composite image of the young open cluster AP 210, constructed from archival HST/ACS observations in F475W (blue), F625W+F658N (green), and F814W (red). The PN appears as a bright blue–green point source near the cluster center because of its strong [O iii], Hα, and [N ii] emission. The white circle indicates the on-sky diameter of a single Hectospec fiber.](https://staging3.plamenu.com/media/11728420940500172801e2cdd0ab2349321167479b17e3b370.avif)
— Open image attachment 1 of 1Color composite image of the young open cluster AP 210, constructed from archival HST/ACS observations in F475W (blue), F625W+F658N (green), and F814W (red). The PN appears as a bright blue–green point source near the cluster center because of its strong [O iii], Hα, and [N ii] emission. The white circle indicates the on-sky diameter of a single Hectospec fiber.