What happens if a black hole suddenly passes by the solar system? How likely is it? What will we see when we find ourselves in the bowels of a dark monster?
Black holes ? one of the most terrifying phenomena in space. The force of their attraction is so monstrous that it bends space and time beyond recognition.
Inevitably, you wonder what will happen if such a monster suddenly appears or flies near our solar system?
To answer this question, it is necessary, first of all, to clarify a number of others. At what distance will it arise? Where will it come from? How massive will a black hole be?
The possibility of a black hole visit
Let's start with the fact that one should not expect such dirty tricks from our Sun: for gravitational collapse, a star is required 10-15 times more massive. There are no such stars in the neighborhood in our galaxy either and are not expected. Are the red dwarfs closest to us? each weighs somewhere between 8-60% of the mass of the Sun.
The red dwarf as seen by the artist
© NASA
In the remainder, we have only two possibilities. First? a black hole spontaneously appears in the neighborhood. Can we reassure the people who are afraid of hadron colliders, large and small? such a danger does not threaten us.
But the second one? more real. In 2000, astrophysicists confirmed the existence of black holes roaming the universe. But, nevertheless, the probability of one of them passing by the solar system is vanishingly small.
But it's worth exploring.
How black holes warp spacetime
At a great distance, a black hole behaves like an ordinary object with a large mass, that is, it obeys the laws of classical mechanics and Newton's law of universal gravitation. In fact, it is impossible to distinguish a blue dwarf weighing 265 suns from a black hole of the same mass by its behavior.
But as soon as we approach the dark monster, the laws of Einstein's general theory of relativity come into play, according to which the force of gravity is capable of bending space-time, especially when it comes to a black hole.
A black hole "in action" as seen by the artist
© ESO / L. Cal? Ada / M. Kornmesser
As you approach a massive monster in a spaceship, you will notice that the closer the black hole gets, the more stress the ship's engines will experience as they try to stay in a circular orbit.
The moment will come when nothing can hold you back from spiraling downward into the black hole's event horizon. Even the light is no longer able to escape from there.
You will find yourself inside a black hole on the way to the singularity, the core of an infinitely curved space-time, in which the laws of physics known to us cease to operate.
As you approach the dark monster, time will begin to slow down. For you, however, nothing will change, but for an observer from outside, time around your ship will begin to flow like syrup. When you find yourself at the event horizon, it will seem from the outside as if you are frozen in stillness. Since light is unable to escape from a black hole, this will be the last thing that will be known about you.
Approaching a black hole
Let's imagine that the incredible happened. A massive black hole outside our galaxy was near a fresh supernova, which pushed the giant at a speed of several hundred kilometers per second in our direction.
How do we know about this?
But in no way. At least until the black hole starts interacting with some visible object? after all, even light is not able to escape from its "bowels".
Therefore, instead of looking for a black hair on a dark carpet, let's think about how to indirectly determine the approach of a giant.
First, matter that has fallen under the influence of a black hole emits streams of particles that can reach us.
Secondly, the curvature of the surrounding space by a black hole can also be noticed by earthlings. Has the gravitational lens predicted by Einstein's general theory of relativity been repeatedly noted by astronomers near massive objects? galaxies, black holes or our sun.
And yet, even under ideal circumstances, it will be difficult to notice the approach of a dark monster. For astronomers to be able to record a change in the radiation of a star, a black hole must pass exactly between it and us, in fact, cross its rays. Even so, it will take a lot of luck to notice this effect.
Finally, a black hole can have a gravitational effect on celestial objects: planets, stars, asteroids and comets. Thus, we come to the original question: how far from the solar system will our hypothetical black star pass?
The black hole in the constellation Unicorn and its companion B (e) -star as seen by the artist
© Casares et al. / Nature / NPG
Judgment Day
It is clear: the closer, the worse for us. Imagine a sparrow flying through a web between tree branches. Close proximity to this monster can change any planetary orbit, turn the entire solar system out of its slots.
If the gravity of the black hole brings our orbit even a little closer to the sun, or vice versa? will move away from it, first of all, will begin monstrous climate changes, unprecedented tsunamis, typhoons and earthquakes.
In the worst case, the passage of a black hole next to us can launch us directly into the hot mouth of the sun, or knock us out of the solar system into the cold hell of space.
As the famous astrophysicist Neil DeGrasse Tyson once put it mildly: "The day when the black hole decides to pay a visit to the solar system will be very sad."
Image of a double black hole
© NASA
Journey to the black hole
Now let's imagine that our guest turned out to be not just a black hole, but a supermassive monster, with an event horizon exceeding five times the entire solar system. Naturally, such a giant will swallow us together with the sun and all the planets like the white shark of the unfortunate tuna.
But will we even be able to look inside the dark monster? Suppose we have created a kind of force field that will protect our planet from any external influences, including the monstrous gravity in millions of G. The Earth in a spiral orbit descends to the event horizon of an unwanted visitor.
In the case of a giant black hole with a mass of five million suns, such as the one right at the center of our galaxy, we have about 16 seconds to descend after crossing the event horizon until we reach the singularity.
Supermassive black hole through the eyes of an artist
© NASA / JPL-Caltech
Will we be able to see the stars on this journey? because the light from them penetrates into black holes? but the curved space-time will greatly change them beyond recognition. It will seem to us that we are looking through the eyepiece of an unimaginable kaleidoscope.
Near the singularity, the entire Universe will shrink around us into a thin strip of shining blue light, and then what remains of the Earth will enter the point of infinite curvature, which is bordered by the space and time we know.