A black hole is a region in space where the gravitational pull is so strong that nothing, not even light, can escape from it. This makes them incredibly difficult to observe directly, as they do not emit any visible radiation. They are formed when massive stars collapse under their own gravity at the end of their life cycle. Black holes play a crucial role in astrophysics, influencing the behavior and evolution of galaxies, and they are also key objects for testing our understanding of gravity and the fundamental laws of physics. While they are intriguing and important objects in the cosmos, there is still much to learn about them, and they remain a subject of active research and exploration in the field of astrophysics.
So now the question arises- What is the largest black hole we know?
Protomassive Black Hole
Protomassive black holes are theoretical objects that are thought to have formed in the early universe through the collapse of massive gas clouds. They are distinct from both primordial black holes (which form from high-density regions in the early universe) and stellar black holes. They are as the name says the size of a common proton and could even take 1 day to swallow a milk jug.While no definitive evidence of protomassive black holes has been found to date, they are of significant interest to astrophysicists.
The Unicorn
Astronomers have apparently found the closest known black hole to Earth, a weirdly tiny object dubbed "The Unicorn" that lurks just 1,500 light-years from us.The nickname has a double meaning. Not only does the black hole candidate reside in the constellation Monoceros , its incredibly low mass - about three times that of the sun — makes it nearly one of a kind. It is tiny- size of Mars.
Saggitarius A
Sagittarius A*, abbreviated Sgr A* is the supermassive black hole at the Galactic Center of the Milky Way. It is located near the border of the constellations Sagittarius and Scorpius. At a distance of 26,000 light-years (8,000 parsecs), this yields a diameter of 51.8 million kilometres (32.2 million miles). For comparison, Earth is 150 million kilometres wide. It has the mass of 4 million suns where the sun is less than a grain of sand compared to it.
M60 Black Hole
The black hole at center of Messier 60 galaxy has the mass of 21 million suns. Half of its stellar mass is in the central sphere and it is 160 light years in diameter. Not much is known about this black hole.
J0045+41
The supermassive black hole in the center of the Andromeda Galaxy is 30 million times more massive than our Sun. Its mass has been calculated by measuring the average speeds of all the stars orbiting the center of the galaxy. The black hole is roughly 10 times as massive as the central black hole in the Milky Way.The supermassive black hole at the center of the Andromeda galaxy has a mass of or 110 to 230 million suns.
M87 Black Hole
The core of the galaxy contains a supermassive black hole (SMBH), designated M87*,[33][70] whose mass is billions of times that of the Earth's SunThis is one of the highest known masses for such an object. A rotating disk of ionized gas surrounds the black hole, and is roughly perpendicular to the relativistic jet. The disk rotates at velocities of up to roughly 1,000 km/s (2,200,000 mph)[74] and spans a maximum diameter of 25,000 AU (3.7 trillion km; 2.3 trillion mi).
TON 618
The winner of this insane competition goes to Ton 618! As a quasar, TON 618 is believed to be the active galactic nucleus at the center of a galaxy, the engine of which is a supermassive black hole feeding on intensely hot gas and matter in an accretion disc. The light originating from the quasar is estimated to be 10.8 billion years old. Due to the brilliance of the central quasar, the surrounding galaxy is outshone by it and hence is not visible from Earth. With an absolute magnitude of −30.7, it shines with a luminosity of 4×1040 watts, or as brilliantly as 140 trillion times that of the Sun, making it one of the brightest objects in the known Universe. It has the diameter of 11 solar systems or 22 times the size of Stephenson 2-18, the largest star known to exist.
The comparison of the orbit of Neptune, Ton 618 and the galaxy Phoenix A.