Astronomers have confirmed the first known microblazar in the Milky Way: a stellar-mass black hole whose relativistic jet happens to be pointed almost directly at Earth. The system, catalogued as IRAS 18293-0941 and lying only about 12,000 light-years away, consists of a black hole and a companion star that completes an orbit every 11.38 days. Material stripped from the star forms an accretion disk that powers two jets racing outward at three-quarters the speed of light. One of those jets is aimed toward us; the opposite jet only becomes visible because it slams into a nearby molecular cloud, carving a bubble and heating gas until it glows.

The object had been sitting in infrared catalogues for decades, hidden behind thick dust that rendered it invisible in ordinary optical images. High-resolution radio observations with the European VLBI Network, combined with the precise stellar position from Gaia, finally pinned the jet to the binary itself rather than to some distant background galaxy. Where the receding jet strikes the cloud, particles appear to be accelerated to energies that may reach the petaelectronvolt range, making this modest stellar system one of the galaxy’s more efficient natural particle accelerators.

The discovery fulfills a theoretical prediction that has been on the books for thirty years. Researchers now plan to watch the jet evolve and to hunt for additional microblazars, which could turn out to play a quiet but important role in how galaxies process energy and cosmic rays. Rest easy, though: at this distance the beam poses no threat to Earth. It is simply a beautifully aligned laboratory sitting in our own backyard.

Read More: https://earthsky.org/space/black-hole-jet-aimed-at-us-galaxy-microblazar/