Free Astronomy Magazine November-December 2025

36 NOVEMBER-DECEMBER 2025 ASTRO PUBLISHING ray (ALMA), whose ability to trace cold gas and dust provides essential context to Webb’s images. While Webb revealed the hot central star and the intricate ionized gas struc- tures within the nebula, ALMA traced the cold molecular gas and dust forming the dense torus at its core. This combination shows how the torus shapes the bipolar “wings” of the nebula and explains why the central star remained hidden for so long. Together, JWST and ALMA provide a comprehensive view of both the hot and cold components of the Butterfly Nebula, offering new insights into the final stages of stellar evolution. The synergy be- tween the two observatories also uncovered surprising chemistry in the Butterfly Nebula. Webb de- tected complex carbon-based mole- The hidden heart of the Butterfly Nebula unveiled by ALMA Observatory Nicolás Lira T he James Webb Space Tele- scope (JWST) has captured un- precedented details of the Butterfly Nebula (NGC 6302), a plan- etary nebula located about 3,400 light-years away in the constellation Scorpius. To gain a complete view of this complex object, astronomers combined Webb’s infrared observa- tions with data from the Atacama Large Millimeter/submillimeter Ar-