Using a new technique, scientists have identified a supermassive black hole lurking in a low-mass, low-metallicity galaxy. Could this discovery be just the tip of the iceberg?
Hunting for Seeds
How did the first supermassive black holes — black holes of millions or billions of solar masses — form?
Artist’s illustration of a primordial galaxy dominated by the supermassive black hole in its center. [NASA/ESA/ESO/Wolfram Freudling et al. (STECF)]Today, we know that giant black holes lie at the heart of most galaxies. Many of them have grown substantially since they first formed, via galaxy mergers and accretion of mass around them. But did they start out as large stars? Or collapse directly from molecular clouds? Or build up rapidly from the merger of smaller black holes?
To identify the seeds of supermassive black holes and address these questions, we need to explore the least-disturbed supermassive black holes that we can find today. Small, low-metallicity galaxies — those that have had a peaceful cosmic history, devoid of the mergers that drive significant black-hole growth — are thus the perfect targets to search for the relics of supermassive black hole seeds.
The catch? These are precisely the environments in which it’s ...