Free Astronomy Magazine July-August 2023

28 JULY-AUGUST 2023 ASTRO PUBLISHING Such events are estimated to occur only a few times each year across the entire Milky Way. Though past observations have confirmed the af- termath of planetary engulfments, astronomers have never caught one in the act, until now. With the power of the Gemini South Adaptive Optics Imager (GSAOI) on Gemini South, one half of the Inter- national Gemini Observatory, oper- ated by NSF’s NOIRLab, astronomers have observed the first direct evi- dence of a dying star expanding to engulf one of its planets. Evidence for this event was found in a telltale “long and low-energy” outburst from a star in the Milky Way about 13,000 light-years from Earth. This event, the devouring of a planet by an engorged star, likely presages the ultimate fate of Mercury, Venus, and Earth when our Sun begins its death throes in about five billion years. “These observations provide a new perspective on finding and studying A possible preview of the ultimate fate of Earth by NOIRLab − Charles Blue, Josie Fenske B y studying countless stars at various stages of their evolu- tion, astronomers have been able to piece together an under- standing of the life cycle of stars and how they interact with their sur- rounding planetary systems as they age. This research confirms that when a Sun-like star nears the end of its life, it expands anywhere from 100 to 1000 times its original size, eventually engulfing the system’s inner planets.