A research team at Keio University conducted detailed molecular spectral line observations of the ultra-high-velocity molecular gas component "Bullet" discovered in the Milky Way Galactic Disc, and clarified its detailed spatial structure, motion, and physical state. I made it.It is possible that the drive source of this Bullet is a temporarily activated black hole (stray black hole).
The research team was conducting a detailed observational study of the supernova remnant W1, which is about 44 light-years from the Sun. This is to accurately and directly measure the kinetic energy that one supernova explosion gives to the interstellar gas.In the process, we discovered a spatially compact high-velocity component in the molecular cloud associated with W1, far from the expansion motion of the supernova remnant. Named "Bullet", this high-velocity component of about 44 light-years in diameter had an extraordinary velocity range of 2 km / s and a velocity completely opposite to the direction of rotation of the Milky Way galaxy (). Reported in 120).
This time, the research team made detailed imaging observations using molecular spectral lines in order to investigate the origin of Bullet.The National Astronomical Observatory of Japan ASTE 10m telescope and Nobeyama 45m radio telescope were used for observation.As a result, this Bullet was found to be a component driven by a local phenomenon that occurred 5000 to 8000 years ago. Due to Bullet's enormous kinetic energy, space / velocity structure, and the fact that no celestial body can be seen in this direction at present, it is highly possible that the drive source is a temporarily activated black hole.
Currently, it is said that 1 to 10 billion black holes are floating in the Milky Way galaxy.This discovery is said to be a very pioneering suggestion of the existence of a stray black hole without a companion star, which had never been observed before.This is expected to advance the research of innumerable allogeneic objects in the Milky Way galaxy.
