TOKYO — New evidence has been found backing the existence of a mid-sized black hole, which was long-theorized to be the middle ground between single star black holes, and supermassive ones found in galaxy centers.

According to a the National Astronomical Observatory of Japan, a team led by Keio University professor Tomoharu Oka discovered a peculiar gas cloud called CO-0.40-0.22 near the center of the Milky Way that contained gas moving at vastly different velocities.

This, along with faint radio waves coming from the center of the cloud, suggest the presence of a black hole a hundred thousand times the mass of our Sun.

The radio signals detected from the cloud are similar to those produced by Sagittarius A, the supermassive black hole at the center of our galaxy.

The Japanese team hypothesized that the midsized or intermediate-mass black hole was formed from the core of a dwarf galaxy that had previously been absorbed into the Milky Way.

Scientists have long believed that giant black holes grow, in part, from the merger of small ones. So the discovery is especially significant since it's the clearest evidence yet of a black hole mass in between the two size extremes.

The team's findings have been published in the journal Nature Astronomy.