User:A Universe Of Knowledge/sandbox

What if a black hole visited our Solar System?

Well, for starters, it certainly wouldn't be good. You can think of a black hole as if it were a sumo wrestler at a buffet: once it wants to eat something, it's going to eat it. And it eats a lot. It doesn't necessarily care what it eats, either; to it, a space rock is just as tasty as some earthling's dessert. So, as you can imagine, if one were to be eyeing up our solar system right now... it wouldn't be good.

Now, I should mention that the probability of one stumbling upon our solar system is extremely rare; almost impossible, in fact. We are very, very small little beings in the scheme of the universe, so having a black hole hit our solar system is like trying to hit a mosquito with a dart. But that's not to say it couldn't happen, either.

Take black holes like V616 Monocerotis in A0620-00, for example. This one in particular seems to be getting a little too close for comfort, at only 3,000 light-years (which is pretty close on the scale of the universe.) Should one of these decide to take a vacation and visit our solar system, it would have no trouble obliterating us.

First and foremost, the black hole would throw rocks at us. And not just pebble sized rocks, either: the largest of these monsters, called asteroids, was Ceres, which had a radius of 469.73 km before it was designated as a dwarf planet back in 2006. As you could imagine, a 939.46 km long rock smashing into the earth would be very, very bad, and render us very, very dead. In addition to asteroids, it would also throw pretty balls of ice and dust known as comets. And while we would be lying down outside admiring the beautiful night sky, outer planets would be bombarded with comets. You have likely seen comets before, and if so, you are probably wondering why something so small could be so bad. Well, the reason why is because they aren't actually as small as you might think.

67P/Churyumov–Gerasimenko easily dwarfs most of Los Angeles, meaning it too could cause some serious damage. Though comets typically burn up as they approach the sun, outer planets don't have the protection of our parent sun, and can take quite a beating. Imagine that the black hole brings a flamethrower to burn them with, and you have basically described a planets description of hell.

The second thing the black hole would do is to throw even bigger objects. And yes, by that I mean planets.

As it passes through our solar system towards the sun, the black hole would cut a swathe of sorts through the planets' orbits. So long as the planets were not not in the immediate vicinity of the black hole at the time, they would be safe, if only momentarily. You see, even if the planets weren't physically there, their orbits would stay fixed; that is, until the black hole came along. It would tangle the orbits up, not unlike spaghetti, and thusly causing the planets to fly all over the place, even to the extent of launching them away. And if, by some random chance, our friend the black hole threw a planet like Jupiter astray and headed towards, say, Earth, we would either decide to follow Jupiter, or get smashed to pieces by it, both of which or equally bad.

But this would just be a warmup. The real onslaught occurs when the black hole actually decides to come and swallow us up. At this point, if evacuation hadn't already begun, we would have just about zero chance of survival, as it would suck up any people leaving (or at least attempting to leave) the solar system What would happen after we left, you might ask?

After everything else was either destroyed or else expelled from our solar system, the black hole would turn its attention to the sun. If the black hole was truly miniscule, having barely enough mass to be considered a black hole, the sun could thwart it in essentially an endless chase between the two, allowing it to survive for a fairly long time. After that, the sun is either consumed by the black hole or simply dies of "old age", where it turns into a black dwarf and proceeds to fade away in some 5.4 billion years. We likely won't be alive to see this, but our solar system will probably look pretty cool. Sure, it may well have patches of it missing and seemingly no specific order, no planets or anything big like them, but there will be some beautiful dust swirling around, as well as comets and other odd things whizzing around. And, perhaps most majestic of all, will be our Sun's substitute: Our Friend...

The black hole.