Mergers with other galaxies may have knocked the black hole in dwarf galaxies off-center, creating "wandering" black holes.
Intriguingly, the Neptune-like planet is is about four times bigger than the star itself.
"Up until now, such a concentration of three supermassive black holes had never been discovered in the universe," Peter Weilbacher, from the Leibniz Institute for Astrophysics Potsdam, said.
The center of our galaxy is located around 26,500 light-years away from Earth.
The latest findings could have important implications for our understanding of how massive stars form.
Researchers estimate that the explosion lasted for approximately 300,000 years.
Astronomers have cast new light on a huge, empty expanse of space that surrounds our galaxy known as the Local Void.
The black hole is located at the center of the spiral galaxy NGC 3147 around 130 million light-years away from Earth.
The findings expand our knowledge of black holes and the galaxies within which they are often found.
Messier 90 belongs to a vast collection of more than 1,200 galaxies known as the Virgo Cluster, which has a diameter of 15 million light-years.
Scientists think that at the heart of nearly every galaxy lies a supermassive black hole (SMBH) with immense gravity.
The image features around 15,000 galaxies, the oldest of which dates back to 11 billion years ago.
The galaxy belongs to a recently discovered, rare and unusual class of stellar systems known as ultracompact dwarfs.
The study has proved the theory holds beyond the Milky Way.
Widening waistbands are truly universal.
Scientists think the galaxy is expanding at about 550 yards per second.
"It's not Swiss watch precision," researchers say.
The fireworks are taking place about 350 million light-years away.