Approximately 1600 years ago, a supernova erupted in the constellation Scorpius, an event recorded in ancient Chinese chronicles. The powerful explosion scattered surrounding gas, generated shock waves, cosmic rays, and intense radiation. In such chaos, it seemed unlikely to expect the calm birth of new stars and the preservation of complex organic chemistry. However, observations using the ALMA telescope have shown the opposite: in the supernova remnant RX J1713.7−3946, astronomers have discovered protected "cradles" of young stars, rich in complex organic molecules.
An international team led by Professor Takashi Shimoonishi from Niigata University used ALMA's high angular resolution (about 0.5 arcseconds) to peer into this extreme region. The results exceeded expectations: two "hot cores" were found—dense, warm clumps of gas around protostars. They contain a variety of molecules, including complex organic compounds and water. Chemically, these objects are similar to ordinary hot cores in quiescent star-forming regions, where organic matter was not subjected to the destructive impact of the supernova.
This is the first such discovery. It was previously believed that the powerful shock waves, cosmic rays, and X-ray radiation should have either destroyed organic molecules or radically altered the chemistry of the environment. However, the molecules have survived. Possible reasons include insufficient time for complete destruction or the protective effect of strong magnetic fields generated by the shock wave, which shield cosmic rays.
Why is this important? Hot cores are precisely the places where stars and planetary systems form. In them, ice mantles with organic matter form on dust grains at low temperatures, which then transition into the gas phase as they heat up. Such molecules could have been precursors to prebiotic chemistry in our Solar System. Analysis of radioactive isotopes suggests that the Solar System also formed not far from the influence of supernovae. The new discovery adds weight to the hypothesis that extreme conditions do not necessarily sterilize the material for future planets.
ALMA observations offer a new perspective on the life cycle of stars. Supernovae not only disperse heavy elements but also appear to contribute to, or at least not hinder, new star formation while preserving chemical complexity. The team plans further research using radio and infrared telescopes to understand whether this scenario is typical or unique to this remnant.
The discovery reminds us how resilient cosmic chemistry can be. Even in the ruins of a stellar explosion, nature finds ways to preserve the building blocks for future worlds. This inspires continued efforts to find answers to the question of how material capable of leading to the emergence of planets, and possibly life, arises and is preserved in our Galaxy.
