ACS HRC image close-up showing the two stars of Pismis 24-1. It was thought to have an incredibly large mass of 200 to 300 solar masses. New NASA/ESA Hubble measurements of the star, have, however, resolved Pismis 24-1 into two separate stars, and, in doing so, have “halved’ its mass to around 100 solar masses.

Credit: NASA, ESA and Jesús Maíz Apellániz (Instituto de astrofísica de Andalucía, Spain). Acknowledgement: Davide De Martin (ESA/Hubble)