Today we're wrapping up our Doomsday Countdown of The Top Five Natural Disasters That Could End The World This Month. Next up? Our Top Five ManMade Catastrophies in which we talk about topics including Singularity, Nanotechnology, and the almighty Grey Goo.
But let's not get ahead of ourselves because today's topic is. . . HUGE! On this day, we explore: black holes gone rogue. And our friends over at Discovery Communications HOWSTUFFWORKS are going to help us out.
As they explain it, black holes rank among the most fearsome phenomena in the universe. Their gargantuan gravity warps space and time—and our understanding of them—almost to the breaking point. From a distance, a black hole acts like any massive, gravitational object—that is, until it’s right on top of you. From a distance, it follows classical mechanics and Newton’s law of universal gravitation, which tells us the attraction between two objects is proportional to their masses and drops off rapidly with distance. In other words, there’s no gravitational difference between R136a1, a blue dwarf star weighing 265 suns, and a 265-solar-mass black hole. But get close enough for a black hole to wrap you in its gravitational sleeper hold—and you’re grappling with a completely different set of rules. . . an EXTREMELY different set.
If you wanted to study a black hole from a starship [and who wouldn't?], you’d find that the closer you got to the monstrous mass, the harder your engines would have to work just to maintain a circular orbit. At first, firing off the occasional rocket burst would suffice to stabilize you; as you closed in, you’d have to expend enormous amounts of energy just to maintain something resembling an irregular orbit. Go closer still, and nonstop rocket burn would be all that stood between you and absolute annihilation.
Once you ran out of fuel (or succumbed to space madness and turned off the engines), you would spiral in to the black hole’s Event Horizon—a boundary beyond which nothing, not even light, can escape. From there, you’d have a date with destiny: Nothing you could do would stop your inexorable journey toward the singularity, a core of infinitely distorted space-time where physics, as we know it, curls up in a ball and whimpers.
Okay . . . so that's what happens out in space. Far away. How's a black hole going to do a flyby on Earth? Where would it come from?
Well, either a black hole would spontaneously form in our vicinity [more on that theory and the Large Hadron Collider next week], or a rogue black hole would just happen to pass nearby. As well-known astrophysicist Neil deGrasse Tyson once told news program 20/20 with his characteristic understatement, “It would be a bad day for the solar system if we got visited by a black hole.”
Here’s the good news: A black hole of typical size moving at a characteristic speed would give us about a hundred years of warning in which to get our act together. A slower moving black hole might give us ten times that long. Either way, the minute we sense one approaching, it’ll be time to start building that space ark—"Danger, Will Robinson. Danger."
For more on rogue black holes and how to spot them, download the new ebook: HOWSTUFFWORKS: The End of the World available December 11.
Is the world ending without you? Quick! Catch-up on our countdown by visiting these links:
End of the World Doomsday Countdown: Day 17
End of the World Doomsday Countdown: Day 18
End of the World Doomsday Countdown: Day 19
End of the World Doomsday Countdown: Day 20
End of the World Doomsday Countdown: In the Beginning
[Wondering what would happen if you fell into a black hole? Watch this video and wonder no more.]