A groundbreaking discovery has shed light on a mystery that had long puzzled scientists – the interaction between a black hole and surrounding objects in space. An international team of astrophysicists, led by Queen’s University Belfast, utilised Nasa’s Chandra X-ray Observatory and other advanced telescopes to make the breakthrough. The revelation has resolved a conundrum that astronomers had been grappling with for years.
The discovery involves a massive black hole that has torn apart a star, using the stellar remnants to impact another star or smaller black hole. This phenomenon provides evidence linking two previously separate mysteries. In 2019, astronomers observed the destruction of a star by a black hole’s gravitational forces, resulting in the star’s remains forming a disc around the black hole. Over time, this disc expanded outward and now intercepts a star or possibly a stellar-mass black hole that orbits the massive black hole at a safer distance.
Lead author Dr Matt Nicholl compared the situation to a diver repeatedly making a splash in a pool, illustrating the collisions between the orbiting star and the debris disc around the black hole. This interaction generates spectacular light displays and bursts of X-rays which have been captured by Chandra. The team’s findings have linked occurrences known as tidal disruption events (TDEs) with quasi-periodic eruptions (QPEs), previously unexplained bursts of X-rays detected in galaxies’ centres.
Co-author Dr Dheeraj Pasham expressed the significance of uncovering the connection between these phenomena, likening it to solving two mysteries simultaneously. Data from various telescopes, including Nasa’s Neutron Star Interior Composition Explorer (Nicer) and the Hubble space telescope, were crucial in elucidating the dynamics around the supermassive black hole. The team’s research, appearing in the October issue of Nature, has provided insights into the mechanisms behind regular eruptions associated with tidal disruptions, paving the way for further exploration in this field.
This breakthrough not only enhances our understanding of celestial phenomena but also has implications for future astronomical observations, particularly in identifying and studying more QPEs linked to tidal disruptions. Tracking these events could offer valuable insights into the prevalence of objects orbiting supermassive black holes and aid in planning for upcoming gravitational wave observatories. Through the collaborative efforts of the international research team, new light has been shed on the mysterious interactions within the vast expanse of space.