X-ray binaries are a fascinating celestial phenomenon that consist of two bodies – a normal star and a compact, dead object like a black hole or a neutron star – with the compact object drawing material from its companion. There are hundreds of such systems known in our Galaxy, showcasing the powerful release of gravitational energy as one of the most efficient processes in the Universe. Among the first X-ray binary systems discovered was Cygnus X-3, known for its intense radio emissions that would fade or disappear in a matter of days, prompting global efforts to coordinate observations and understand its behavior. This system, dubbed the “astronomical puzzle Cygnus X-3,” has been the subject of extensive research since the 1970s.
The breakthrough in unraveling the mystery of Cygnus X-3 came with the use of the Imaging X-ray Polarimetry Explorer (IXPE) satellite launched by NASA in December 2021. By studying the system with X-ray polarized vision, researchers like lead author Alexandra Veledina were able to gain insights into the configuration of matter surrounding the compact object in close proximity to the black hole. They discovered that the compact object is surrounded by a dense, opaque envelope of matter, with observed light reflecting off the inner funnel walls created by surrounding gas, resembling a cup with a mirrored interior. This finding identified Cygnus X-3 as an ultra-luminous X-ray source (ULX), consuming matter at an exceptional rate with a significant portion of material being ejected from the system.
ULXs are typically observed as bright spots in images of distant galaxies, their emissions amplified by the focusing effects of the compact object’s surrounding funnel acting like a megaphone. However, due to the vast distances to these sources, they appear relatively faint to X-ray telescopes. The discovery of a bright counterpart of these distant ULXs within our own Galaxy, as revealed by the study of Cygnus X-3, marks a significant advancement in our understanding of these extreme cosmic phenomena. This finding offers new opportunities for investigating the nature of ultra-luminous X-ray sources and exploring the processes involved in extreme matter consumption.
The identification of Cygnus X-3 as a member of the ULX class opens up new avenues for studying this extraordinary cosmic source and delving deeper into the mechanisms of matter consumption in X-ray binary systems. This discovery sheds light on the behavior of such systems and provides valuable insights into the processes at play in these extreme environments, informing our understanding of the dynamics of compact objects like black holes and neutron stars. The use of X-ray polarized vision has proven instrumental in unlocking the secrets of Cygnus X-3 and unveiling its true nature as an ultra-luminous X-ray source exhibiting unique characteristics that challenge our current understanding of these cosmic phenomena.
In conclusion, the investigation of X-ray binary systems like Cygnus X-3 with advanced technologies such as the IXPE satellite has provided groundbreaking insights into the nature of ultra-luminous X-ray sources and the processes involved in extreme matter consumption. This discovery marks a significant milestone in the study of cosmic phenomena and offers new opportunities for further exploration of X-ray binaries and their mechanisms. By unveiling the mysteries of Cygnus X-3 and identifying it as a member of the ULX class, researchers have opened up new possibilities for understanding the behavior of these systems and expanding our knowledge of the Universe’s most powerful forces.