Black holes have been an enigmatic subject for scientists and mathematicians since humankind first theorised they existed in 1916.
After a breakthrough study announced in April 2019 that they’ve captured the first direct photographs from the edge (event horizon) of a black hole, astronomers have bucked up and are deconstructing the photograph and carrying out extensive studies on black holes themselves, and how they can be better imaged. Now, the largest-ever black hole observed has come into focus.
Dr Kianusch Mehrgan and the team of researchers at Max Planck Institute have found what appears to be the largest black hole ever observed, about 700 million light-years away from the Earth at the heart of a galaxy called Holm 15A. It is roughly twice the size of the record-holding black hole it displaced — the black hole at the centre of galaxy NGC 1277, which is ~11 times as wide as the orbit of Neptune around the sun. Researchers believe the black hole in Holm 15A is at least 10,000 times as massive as our home galaxy’s black hole.
The research team used data captured by the Very Large Telescope array, and additional data from the La Silla Observatory, both of which are operated by the European Southern Observatory in the Atacama Desert in Chile. These were also the same telescopes used to capture the iconic first photograph of a black hole’s event horizon. The team was able to use the data to map the structure of the Holm 15A galaxy in remarkable detail. This was then used to run simulations to study galaxy formation and its fuzzy black-hole centre.
The researchers think it’s possible that the black hole ate up the stars surrounding it, or pushed them away. The incredibly massive size of the black hole means that despite being hundreds of millions of light-years away, it makes for a great candidate to image using the technology available today.