First Microblazar Discovered in the Milky Way Galaxy

Detection and Characteristics of IRAS 18293−0941

While full-scale blazars consist of supermassive black holes millions or billions of times the mass of the sun firing jets directly at Earth, IRAS 18293−0941 features a stellar-mass black hole up to a few hundred times solar mass. The system was hidden behind a thick wall of interstellar gas and dust, making it virtually invisible in ordinary optical images despite being cataloged decades ago. Everything about IRAS 18293−0941 was hiding in plain sight, said research leader Josep Martí of the University of Jaén, Spain, in a statement. It sits behind so much dust that it is essentially invisible in ordinary optical images. It was catalogued decades ago and then more or less forgotten. Discovery of the system began when researchers noticed the light of the system’s star flickering, revealing the 11.4-day orbit of a companion black hole observed almost face-on. Radio wave observations subsequently exposed a one-sided jet, with the opposite jet pointing directly away from Earth. High-resolution imaging by the European VLBI Network confirmed the orientation and origin of the jet. This was the moment the result became solid, explained Benito Marcote from the Joint Institute for VLBI in the Netherlands. The resolution achieved by the EVN position together with the known position of the star from the Gaia satellite confirmed it: the jet belongs to the stellar system.

Particle Acceleration and Cosmic Gamma-Ray Emissions

Although the receding jet cannot be observed directly, astronomers detected its impact using the MeerKAT radio observatory in South Africa, uncovering a 100 light-year-wide bubble where the jet strikes interstellar material. At the edge of this bubble lies a hotspot where particle collisions accelerate matter, warm dust, and cause hydrogen gas to glow. This collision point also serves as a source of high-energy gamma-rays, carrying ten times the energy of particles accelerated by the Large Hadron Collider (LHC), Earth’s largest and most powerful particle accelerator. The jet carries 500,000 times the energy radiated by the sun, shedding light on how feeding black holes operate as powerful cosmic particle accelerators. The elegance is that the accelerator engine and the target are two different objects, tens of parsecs apart, noted team member Pedro Luque-Escamilla of the University of Jaén. The jet does the accelerating. The cloud does the shining.

Implications for Future Astronomical Research

Finding a microblazar significantly closer to Earth than distant active galaxies provides a distinct opportunity to examine the evolution of such systems and how they transfer energy to surrounding galaxies. The research team has made their findings available as a preprint on the repository site arXiv, and the work has been accepted for publication in the journal Astronomy & Astrophysics.