Free Astronomy Magazine May-June 2025

MAY-JUNE 2025 T his graph shows the near-infra- red spectra of LMC68, obtained 8.58 days after the eruption with the Carnegie Institution’s Magellan Baade Telescope (black), and 22.49 days after with the Gemini South telescope (red), one half of the In- ternational Gemini Observatory, funded in part by the U.S. National Science Foundation and operated by NSF NOIRLab. The ionized silicon emission around 1.4 microns domi- nates both spectra. Apparent emis- sion features around 1.8-2 microns are a result of contamination from Earth’s atmosphere. [International Gemini Observatory/NOIRLab/NSF/ AURA/T. Geballe/J. Pollard] Its most recent eruption, in August 2024, was first captured by the Neil Gehrels Swift Observatory, which has been closely monitoring the nova every month since its 2020 eruption. Given its known recurrent timescale, astronomers were antici- pating this eruption, and LMC68 de- livered right on cue. Follow-up observations were con- ducted nine days after the initial outburst with the Carnegie Institu- tion’s Magellan Baade Telescope, and 22 days after the initial out- burst with the Gemini South tele- scope, one half of the International Gemini Observatory, funded in part by the U.S. National Science Foun- dation and operated by NSF NOIR- Lab. Using the technique of spec- troscopy, the team observed LMC68’s near-infrared light, which allowed them to study the nova’s ultra-hot phase during which many elements have been highly ener- gized. By studying this phase as- tronomers can learn about the most extreme processes at play in the eruption. This study is the first ever near-infrared spectroscopic observa- tion of an extragalactic recurrent nova. After its initial eruption LMC68’s light faded rapidly, but Gemini South’s FLAMINGOS-2 instrument still captured a strong signal from