The supermassive black hole V616 Monocerotis is the closest to our Earth at a distance of just 3,300 light-years away. Supermassive black holes like V616 are monstrous wells of gravity, typically found at the dead centre of galaxies. But there could be another, secretly hidden black hole somewhere much closer to our home planet if two Japanese astrophysicists are correct. According to astronomers Daichi Tsuna and Norita Kawasaki from the University of Tokyo, past studies show there could be up to 100 million black holes hiding throughout the Milky Way.

The astrophysicists presented the shocking claim in a study, pre-published on the archiving website Arxiv. The researchers believe the Milky Way is heavily populated with a particular type of black hole that is incredibly hard to detect. Black holes tend to come in all shapes and sizes, ranging from stellar black holes to supermassive black holes. Supermassive black holes like Sagittarius A* in the heart of the Milky Way are a common sight throughout the cosmos. READ MORE: Former NASA scientist claims there's a BLACK HOLE inside of Earth

Black hole shock: Millions of hidden black holes could be lurking in the Milky Way

Black holes are 'black' because their gravity absorbs light

There could, however, be millions of so-called “isolated black holes” (IBHs) peppered throughout the Milky Way. Isolated black holes are considerably smaller than their supermassive cousins and are also harder to detect. Black holes absorb all light unlucky enough to fall towards their point of no escape – the event horizon. As a result, black holes are virtually impossible to directly observe from Earth. READ MORE: First-ever image of black hole PROVES 'we're racing' to doom

Black holes that absorb a lot of material do, however, emit vast amounts of X-rays to help reveal their location.

100,000,000 isolated black holes are believed to be lurking in our Galaxy Daichi Tsuna and Norita Kawasaki, University of Tokyo

Isolated black holes are an exception to this rule because they are poor at converting the stellar material they absorb into detectable X-rays. Instead, the Japanese duo of astrophysicists hopes to detect the potential millions of black holes through other means, such as radio waves. They wrote in their study: “Apart from the few tens of stellar-mass black holes discovered in binary systems, an order of 100,000,000 ( 10^8) isolated black holes are believed to be lurking in our Galaxy. READ MORE: NASA astronomer hints universe could be a HOLOGRAM

Black hole researchers can detect the objects through X-ray emissions

Isolated Black Holes are harder to detect because they do not emit as many X-rays

“Although some IBHs are able to accrete matter from the interstellar medium, the accretion flow is usually weak and thus radiatively inefficient, which results in significant material outflow. “We study electron acceleration generated by the shock formed between this outflow and the surrounding material, and the subsequent radio synchrotron emission from accelerated electrons.” As a black hole slowly absorbs the stellar gas and dust that drifts in the space in-between stars, a lot of the material is ejected back into space at high speeds. If the stellar material moves fast enough to produce radio waves, scientists on Earth should be able to trace the signals back to the black holes.