Astronomers believe that supermassive black holesThe largest black holes are called "supermassive." These black holes have masses that are more than 1 million suns together. Scientists have found proof that every large galaxy contains a supermassive black hole at its center. The supermassive black hole at the center of the Milky Way galaxy is called Sagittarius A.https://www.nasa.gov › nasa-knows › what-is-a-black-hole-k4
M33: A Galaxy with No Supermassive Black Hole.
In the region of the Universe visible from Earth, there are perhaps 100 billion galaxies. Each one has about 100 million stellar-mass black holes.
A single Black Hole, even one at the center of our Milky Way galaxy, is just too small to eat an entire galaxy.
No. There is no way a black hole would eat an entire galaxy. The gravitational reach of supermassive black holes contained in the middle of galaxies is large, but not nearly large enough for eating the whole galaxy.
'Dead' Galaxies Mysteriously Ran Out of Fuel to Make Stars in Early Universe. Taking advantage of a phenomenon that allows astronomers to use massive galaxy clusters as natural magnifying glasses, researchers have discovered strange galaxies that stopped making stars before their time.
Black holes do not have "event horizons" beyond which there is no return, according to renowned physicist. Black holes do not exist—at least, not as we know them, says renowned physicist Stephen Hawking, potentially provoking a rethink of one of space's most mysterious objects.
Located just under 1,600 light-years away, the discovery suggests there might be a sizable population of dormant black holes in binary systems. The black hole Gaia BH1, seen in this artist's concept near its Sun-like companion star, is the closest black hole to Earth discovered so far.
It is incredibly unlikely that Earth would ever fall into a black hole. This is because, at a distance, their gravitational pull is no more compelling than a star of the same mass.
As black holes evaporate, they get smaller and smaller and their event horizons get uncomfortably close to the central singularities. In the final moments of black holes' lives, the gravity becomes too strong, and the black holes become too small, for us to properly describe them with our current knowledge.
Wormholes are shortcuts in spacetime, popular with science fiction authors and movie directors. They've never been seen, but according to Einstein's general theory of relativity, they might exist.
Since nothing can escape from the gravitational force of a black hole, it was long thought that black holes are impossible to destroy. But we now know that black holes actually evaporate, slowly returning their energy to the Universe.
That connection led to the creation of a model that proposes that spacetime can be created or destroyed by changing the amount of entanglement between different surface regions of an object.
Black holes are so massive that they severely warp the fabric of spacetime (the three spatial dimensions and time combined in a four-dimensional continuum). For this reason, an observer inside a black hole experiences the passage of time much differently than an outside observer.
The technology required to travel between galaxies is far beyond humanity's present capabilities, and currently only the subject of speculation, hypothesis, and science fiction. However, theoretically speaking, there is nothing to conclusively indicate that intergalactic travel is impossible.
Scientists suppose that in about four billion years the star formation will stop, which is almost just a blink of an eye in the life cycle of the universe. The Milky Way is dying and we don't know why.
1 second in space is equal to 1 second in earth. Space time doesn't move any faster than earth time so we use earth time for all of outer space.
In their paper, the authors consider a hypothetical example with w = −1.5, H0 = 70 km/s/Mpc, and Ωm = 0.3, in which case the Big Rip would happen approximately 22 billion years from the present. In this scenario, galaxies would first be separated from each other about 200 million years before the Big Rip.
In order for you to stop time, you would have to be traveling infinitely fast. Nothing can travel faster than light (let alone infinitely fast) without gaining infinite mass and energy, according to Einstein's theory of relativity.
Eventually, the entire contents of the universe will be crushed together into an impossibly tiny space – a singularity, like a reverse Big Bang. Different scientists give different estimates of when this contraction phase might begin. It could be billions of years away yet.
Stellar black holes are very cold: they have a temperature of nearly absolute zero – which is zero Kelvin, or −273.15 degrees Celsius. Supermassive black holes are even colder. But a black hole's event horizon is incredibly hot. The gas being pulled rapidly into a black hole can reach millions of degrees.
Black holes are dark, dense regions in space where the pull of gravity is so strong that nothing can escape. Not even light can get out of these regions. That is why we cannot see black holes—they are invisible to our eyes. Because nothing can get out of black holes, physicists struggle understanding these objects.
Even though certain features of the universe seem to require the existence of a multiverse, nothing has been directly observed that suggests it actually exists. So far, the evidence supporting the idea of a multiverse is purely theoretical, and in some cases, philosophical.
Black holes themselves cannot be seen: their gravitational fields are so strong that nothing can escape them—including light. That is why their edges are called event horizons, because, much like with normal horizons, seeing beyond them is impossible.