These areas of space-time arise when, at the end of their life cycle, massive stars collapse and can continue to grow by absorbing stars and merging with other black holes. This interaction has fascinated scientists for decades, who have used it to identify their presence because electromagnetic radiation is emitted as visible light throughout the universe. Astronomers have observed a number of stellar black holes in binary systems and found that a radio source known as Sagittarius A * in the core of the Milky Way galaxy contains a supermassive black hole with a mass of about 4.3 million solar masses.
The two types of cosmic phenomena are completely different, but Harvard University astrophysicist Fabio Pacucci revealed during the TedTalk conference how both present their own unique risks.
He said: “Most of the black holes we found can be considered as two main types ̵1; smaller ones, called stellar-mass black holes, weigh up to a hundred times the mass of our Sun.
“They form when a material star consumes all its nuclear fuel and its core collapses.”
“We have observed several of these objects as close as 3,000 light-years away, and there could be up to 100 million small black holes in the Milky Way.”
“Should we be afraid?” Probably not. “
However, Dr. Pacucci theorized one way that this type of black hole could pose a threat.
He added: “Despite their large mass, stellar black holes have only a radius of about 300 km or less, so the chances of a direct hit with us are slim.
“Although, because their gravitational fields can affect the planet from a great distance, they could be dangerous without a direct collision.”
“If a typical black stellar mass hole were to pass through the area of Neptune, the Earth’s orbit would change significantly, with catastrophic consequences.”
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“The constant combination of how small and huge the galaxies are means that stellar black holes don’t worry us much.”
Dr. Pacucci does not think this is a likely scenario that will be developed in the near future, but he sent a warning against another type of space anomaly.
He added: “However, we still have to encounter the second type – supermassive black holes.
“These have millions or billions of times more mass than our Sun and have event horizons that could span billions of miles.”
“These giants have grown to immense proportions by swallowing matter and merging with other black holes.”
“Unlike their stellar cousins, supermassive black holes do not roam the universe.”
“Instead, they lie in the center of galaxies, including our own, which is in a stable orbit around one in the center of the Milky Way at a safe distance of 25,000 light-years.”
Dr Pacucci noted that scientists are already predicting how this black hole could cause chaos for billions of years.
He continued: “That could change.
“If our galaxy collided with another, Earth could be thrown toward the galactic center, close enough to the supermassive black hole to eventually engulf it.”
“In fact, the collision with the Andromeda Galaxy is expected to take four billion years, which may not be great news for our planet.”