Astronomers from Harvard University, USA, together with scientists from the Black Hole Initiative (BHI) have developed a new method for detecting black holes in the outer part of the solar system, which will also make it possible to determine once and for all the nature of the hypothetical Ninth Planet. This work asserts the possibility of using the future Legacy Survey of Space and Time (LSST) sky survey to observe accretion flares, which will help to confirm or disprove the hypothesis that Planet 9 may actually be a black hole.
In their work, scientists led by Amir Siraj, an undergraduate student at Harvard University, developed a new method for searching for black holes in the outer solar system, based on observations of flares that occur when a black hole bursts a passing comet. This study shows that the LSST sky survey is capable of detecting black holes by observing accretion flares that occur when colliding with small objects in the Oort cloud.
“In the vicinity of a black hole, small bodies approaching it melt as a result of heating due to the energy that is released when the black hole absorbs matter from the surrounding interstellar space,” Sirazh said. "Once melted, small bodies are tidal burst, and their remains fall onto the black hole, causing flares."
Modern technology does not allow these accretion flares to be detected without prior guidance, but the LSST sky survey can easily make such detections, Sirazh explained. These observations will also test the hypothesis that the hypothetical Planet 9, whose existence well explains the unusual orbits of objects in the Kuiper ice belt located in the outer solar system, could be a primordial black hole, he added.
The study has been accepted for publication in the Astrophysical Journal Letters and is available for review at the arxiv.org online repository.