1.5 million km/h: Supersonic winds detected in a system where a hidden black hole is consuming a star.

Scientists utilized the XRISM X-ray space telescope for the most detailed study to date of the binary system Cygnus X-3, located 32,000 light-years away from Earth. It is known that this system contains a massive Wolf-Rayet star and a hidden black hole, although astronomers only suspect that it is indeed a black hole. The findings of the research have been accepted for publication in the Astrophysical Journal, reports Space.

The binary system Cygnus X-3 is intriguing to scientists for various reasons. It is believed to consist of a stellar-mass black hole and a rare type of star known as a Wolf-Rayet star. These are extremely massive hot stars that are in the final stages of their evolution, emitting a very strong stellar wind that carries their gas into space.

The suspected black hole and star are so close to each other that they complete one orbit around each other in just 5 hours. Therefore, astronomers speculate that the black hole may gradually be consuming its neighboring star.

However, what particularly fascinates astronomers is the nature of the Wolf-Rayet star in the binary system Cygnus X-3. The strong stellar winds emitted by the star carry its gas outward, surrounding the system. Meanwhile, the suspected black hole captures some of this gas and heats it up, causing it to emit X-ray light.

Due to the dense clouds of dust and gas surrounding the Cygnus X-3 system, which absorb visible light, scientists have been able to peer into the binary system using X-ray radiation.

Observations from the XRISM telescope have allowed astronomers to gain the best insight into the behavior of stellar gas in this system, including the gas being expelled from the Wolf-Rayet star. Astronomers concluded that the suspected black hole is actively interacting with the gas ejected by the star in the form of stellar winds. Additionally, scientists discovered the existence of a turbulent region in the system, which arises from the movement of the hidden black hole through the stellar gas.

The star expels its gas both towards Earth and in the opposite direction. Researchers found that the speed of the stellar wind directed towards us is 1.5 million km/h, which is approximately 1,000 times faster than the speed of sound on Earth. The stellar wind directed in the opposite direction travels at a slower speed.

According to astronomers, further observations of the binary system Cygnus X-3 based on the obtained data will help determine whether there truly is a stellar-mass black hole present or something else, possibly a neutron star. If so, the assumption that this object is consuming its neighboring star would be dismissed.