Although it is well established they reside in seemingly all galaxies we do not know how they get so enormous.
They modeled their data and found that the structure is a very promising candidate for an intermediary black hole (IMBH) - a hypothetical class of black hole with mass in the range 100 to one million solar masses. The finding was also supported by further simulations of the gas movements. Astronomers have long chased evidence of mid-sized black holes - black holes larger than the ones formed from a single star, but still much smaller than supermassive black holes.
"Further detection of such compact high-velocity features in various environments may increase the number of non-luminous black hole candidate and thereby increase targets to search for evidential proof of general relativity".
The presence of the mid-sized black hole so close to Sagittarius A* - a mere 200 light years away - could provide valuable fuel to the theory that smaller black holes drift towards the centre of the galaxy, coalescing into bigger black holes until they join the supermassive centre point. "We have already detected several candidates for stray black holes". The speculated black hole is unique regarding size.
But such black holes had not previously been reliably detected and their existence has been fiercely debated among the astronomical community.
One hypothesis, which scientists have always been looking to confirm, is the presence of what's called intermediate-mass black holes, which researchers think might act as seeds for their more massive counterparts. IMBHs are a newer theory; and while many have been proposed, none have been accepted yet. An absolutely huge black hole 100,000 times more massive than the sun has been discovered in a toxic gas cloud near the heart of the Milky Way.
"Based on the careful analysis of gas kinematics, we concluded a compact object with a mass of about 100,000 solar masses is lurking in this cloud", Prof Oka added.
If confirmed, the phenomena will measure in as an intermediate-mass black hole; a potentially enlightening link between the small black holes, which are born when stars end their lives, and supermassive black holes, existing at the hearts of galaxies.
Prof Oka said it suggests 'this massive object is an inactive IMBH which is not now accreting matter'.
Studies have suggested there could be between 100 million to 1 billion black holes in the Milky Way alone, but only about 60 have been identified. IMHBs have never been officially identified, though. While the existence of such a black hole in our galaxy has nearly been settled, not the same can be said for other types of black holes.