Free Astronomy Magazine January-February 2022

JANUARY-FEBRUARY 2022 T his artist’s impression shows the bright core of a Wolf–Rayet star surrounded by a nebula of material which has been expelled by the star itself. Wolf–Rayet stars are hot and massive with lifespans of a few mil- lion years. They are thought to end in dramatic supernova explosions, ejecting the elements forged in their cores into the cosmos. [ESO/L. Calçada] end of their lives, help us, in a way, to maintain good dental health!” jokes Franco. Besides these stars, other scenarios for how fluorine is produced and ex- pelled have been put forward in the past. An example includes pulsations of giant, evolved stars with masses up to few times that of our Sun, called asymptotic giant branch stars. But the team believes these scenar- ios, some of which take billions of years to occur, might not fully ex- plain the amount of fluorine in NGP–190387. “For this galaxy, it took just tens or hundreds of millions of years to have fluorine levels comparable to those found in stars in the Milky Way, which is 13.5 billion years old. This was a totally unexpected result,” says Chiaki Kobayashi, a professor at