A recent study conducted by a team of astronomers utilizing NASA’s Chandra X-ray Observatory has unveiled critical insights into the challenging environments for planet formation within the star cluster Cygnus OB2. Located approximately 4,600 light-years from Earth, Cygnus OB2 is home to hundreds of massive stars that emit high-energy radiation capable of disrupting the delicate disks of dust and gas that form new planets.
The researchers employed a combination of X-ray, ultraviolet, optical, and infrared data to map the cluster, revealing areas where the chances of planetary formation are significantly reduced. The study highlights the impact of massive stars on their surroundings, particularly through the process of “photoevaporation,” where radiation accelerates the evaporation of planet-forming disks, diminishing their potential to coalesce into planets.
In regions with high concentrations of massive stars, the fraction of young stars retaining their disks plummets to about 18%, compared to approximately 40% in less irradiated areas. The most hazardous zones for budding planetary systems are found within 1.6 light-years of these massive stars, where intense radiation accelerates disk evaporation.
The study also explored the diffuse X-ray emissions in Cygnus OB2, discovering that higher-energy emissions originate from gas winds from massive stars colliding, heating the gas and producing X-rays. This comprehensive analysis provides a clearer understanding of the interplay between star formation and planetary system development in dense stellar environments.
Two papers detailing these findings are published in the November 2023 issue of the *Astrophysical Journal Supplement Series*. The research underscores the complex dynamics of star clusters and their profound effects on potential planetary systems.
NASA’s Marshall Space Flight Center manages the Chandra program, with science operations overseen by the Smithsonian Astrophysical Observatory.