An international team of scientists spotted a massive black hole from the early stages of the universe that eventually became too large even for its host galaxy to contain.

Astronomers from Oxford University, Harvard University, the University of Hawaii, ETH Zurich, the Max-Planck Institute, the INAF-Osservatorio Astronomico di Roma and Yale University made the discovery while mapping the development of supermassive black holes throughout the course of cosmic time.

"Our survey was designed to observe the average objects, not the exotic ones," C. Megan Urry, astrophysics professor at Yale and co-author of the study, explained.

"This project specifically targeted moderate black holes that inhabit typical galaxies today. It was quite a shock to see such a ginormous black hole in such a deep field."

According to the researchers, the gigantic black hole was formed during the early universe, around 2 billion years after the event known as the Big Bang. The cosmic occurrence is located at the CID-947 galaxy, and is 7 billion solar masses in size; it is considered one of the largest black holes to be found in history.

What surprised the researchers the most, however, was the galaxy mass that surrounded the black hole.

ETH Zurich researcher and lead author of the study Benny Trakhtenbrot said that the galaxy's mass measured at about the same size as most other galaxies. This shows that the supermassive black hole existed in an average-sized galaxy.

Most other galaxies in the universe, such as the Milky Way, typically feature a black hole at their core, which often holds a very large number of solar masses. The findings of the study contradict earlier notions that galaxies expand in size relative to their black holes, as well as challenge previous theories that the radiation that results in the expansion of black holes restricts the formation of stars.

The researchers believe that stars were being formed in the galaxy CID-947, and that the galaxy itself could still continue to develop. It could become the antecedent of the most massive and extreme systems that exist in the modern-day universe, including the NGC 1277 galaxy in the constellation Perseus that is located around 220 million light years away from the local Milky Way galaxy.

If this is true, the development of the massive black hole significantly anticipated the development of its galaxy, contradicting what scientists initially thought.

The findings of the multi-organizational study are featured in the journal Science.