Overview
- A team led by Silke Britzen at the Max Planck Institute reports a candidate close supermassive black hole binary in the galaxy Markarian 501, with findings accepted by Monthly Notices of the Royal Astronomical Society.
- The 23-year radio dataset reveals two distinct particle jets from the galaxy’s core, where only one had been seen before, with the fainter jet shifting position in a way that suggests orbital motion.
- In June 2022 the system’s emission briefly formed an Einstein ring, a lensing effect the team says occurs as the front black hole bent light from the jet behind it.
- From the tracked motion, the researchers estimate an orbital period of about 121 days and a separation of roughly 250 to 540 astronomical units, which points to a possible merger in about 100 years.
- Such a pair would radiate ultra-low-frequency gravitational waves that could be picked up by pulsar timing arrays, which use precise measurements of pulsar radio pulses to sense spacetime ripples.