Does anyone else find this...unsettling? Floating around in the void of space, alone, is an almost invisible monster that can gobble planets and stars.
It can't really "gobble" anything any more than a star "gobbles" things that fly into its photosphere or a planet "gobbles" things that crash into it.
Unless you cross its event horizon, its gravity works just like any other celestial object. Maybe at worst it slingshots you off in a different direction.
If I was going to be afraid of an invisible killer, I would be far more concerned with gamma-ray bursts. It covers a much larger area than that a black hole and could crisp our planet like some kind of sci-fi intergalactic superweapon laser beam. And some might consider getting turned to ash in mere moments a mercy compared to the potential of a near "miss" that would give half the planet instant cancer and completely fuck our weather patterns beyond any comprehension.
Still not super likely, but I would think far more likely than a direct hit by a black hole.
A mass of 6x to 7x our sun (size of this object) would start messing with solar system orbits well before it got here. Not that that would be much better for us!
We would most likely freeze to death. As the black hole crossed the asteroid belt we would be pulled away from the sun as it started to compete with the black hole's gravity. Depending how fast the black hole was moving we might die over a few months or we might freeze to death in a few days. Probably there are paths where the earth would briefly be pulled into an elliptical orbit, and then we would be burnt to a crisp as we circled back close to the sun.
> wouldn’t want society to know we were about to collide with a star-sized mass
I may be misunderstanding the distances involved but wouldn't such a collision take centuries if not thousands of years to play out? For the most part it would just look like we had 2 suns, one of which gets a few millimeters bigger (to the naked eye) every year.
ah dammit I didn't think of that
you're right it would be more of a disturbed orbit, weird ass days and nights
but hey atleast there's a chance the scientists could have close up real life simulation of the three body problem
Fortunately space is really, really, really, really, really, really, REALLY big. The chance of this happening is so infinitesimal we might as well worry about spontaneously transforming into a whale or potted flower manifested a mile above the surface of our planet.
I'd wager such an encounter is way more likely to result in any of:
1) the Earth being flung out of the Sun's orbit
2) planetary orbits becoming disrupted such that an encounter with another planet over the coming years or millennia becomes likely,
2.1) which could eventually have the same "flinging away from the Sun" effect,
2.2) or (unlikely, but possible) result in a collision
2.3) or result in the Earth being shredded into asteroids
2.4) or other planets suffering that fate and then showering the Earth with dangerously-large asteroids over a period of decades or centuries until it's nearly, or actually (think: outright crust liquefaction from impacts) lifeless.
than the Earth actually getting swallowed up, by at least an order of magnitude.
IOW, the most-likely "we're all dead" outcomes for us, from a close encounter with a massive rogue anything really, including a black hole, might take years and years to play out.
Detection typically requires exceptionally rare circumstances - which if looking at a dataset the size of the visible universe, typically turns up several examples if we look hard enough.
But any specific random example, is often brutally hard to see.
I'm pretty sure it would be something like even if a star was coming and we saw it what the fuck could we even do
it would just create mass panic, hysteria and would make everyone hella religious
depending on how early we detect it though we might have some time to make good memories before we die.
atleast I would prefer a black hole smashing into us unbeknownst to us instead of a known star. Also no one would want to show up to jobs and stuff
That brings me memories of Cosmos 1999. The moon left Earth's orbit to outer space because explosions, but being slingshoted away because a nearby massive enough object passing by looks like a more possible scenario, not explored enough by sci-fi.
The basic premise of the show that an explosion at a nuclear waste dump could produce enough energy to push the Moon out of the Solar System to wander the galaxy is an interesting product of its time. Concerns over the power of nuclear explosions was high and casual access to knowledge about the plausibility of such a scenario was somewhat limited.
There's a fan driven update called Space: 2099 that improves some of the more dated aspects of the show, including showing the Moon enter some type of portal or wormhole to make suspension of disbelief easier. While the Special Edition releases of Star Wars often suffered from updating certain aspects, especially special effects, the Space: 2099 changes were generally good for the show. Too bad they're unable to fund raise enough and get permission to do the entire series.
Space: 1999. Do you happen to be french or polish?
In Germany they called it "Mondbasis Alpha". As I child I really liked this series and it's predecessor UFO made by the same team (Gerry and Sylvia Anderson of Thunderbirds fame).
Direct interaction isn't needed for havoc. A supermassive object sweeping by the Solar System could destabilize Jovian orbits. In the Nice model, Neptune flung Kuiper belt asteroids sunward, gifting the inner planets with a late heavy bombardment.
Rogue gas giants, brown dwarfs accelerated to relativistic speeds, giant asteroids approaching from the Sun's direction, Carrington Events, an ill-directed gamma ray, etc. So many ways life on Earth can see its 250 million remaining years cut short, and those are only a few of the cosmic threats we can imagine.
A black hole with a Schwarzschild radius of 20 km would weigh about 6.8 Solar masses. It wouldn't even need to get super close to affect the Solar System.
No more unsettling than space in general is. It’s pretty hostile to life. We’re not just making turns around the orbital racetrack setup around the Sun, we’re also flying through space following the gravitational trail of the Sun as it races forward without a destination.
I was playing with Universe Sandbox over the weekend trying to figure out how to terraform Venus. Changing its axial rotation period to a day to match the Earth while I screwed around with its chemistry was enough to cause Europa and some of the other famous moons of Jupiter and Saturn as well as Charon to yeet themselves outside of the solar system within about 10 or 20 years of simulated time.
Why would changing the rotation speed of Venus have any noticeable effect on the outer planets? That sounds more like a limitation of the model than anything else. Especially over such a short time! 20 years is nothing to the orbit of Charon.
Probably, but if a Venus-sized mass showed up in the inner solar system because the Sun just picked it up along the way, it might not be instant death but we’re probably in for a rough time. It doesn’t have to be a black hole that does us in, it could be something much smaller that still strips the Moon away or causes Earth to readjust its own position in a way we, as in life, but also maybe we as in humans or we as in mammals just don’t like very much in a very short amount of time temporally speaking, and we couldn’t do anything about it anymore than we could do anything about a black hole because we’re just not the captains of this ship. We’re just some homegrown stowaways.
But for what it’s worth, it’s also just so incredibly unlikely it’s not a scenario worth thinking about either, and thinking about it too much just invites existential dread.
It would be nice to get a rigorous estimate on how big and nearby a black hole could be before we'd notice it with routine sky surveys or orbital deviations. A 6-solar-mass black hole only has a radius of around 18km or 11 miles. How often will one pass in front of a star precisely enough for OGLE and MOA to detect it, as they did with this one?
Apparently the Roman Space Telescope will be great at detecting these, if it doesn't get cancelled.
There are many theoretical astronomical risks. For example, if we happened to come into the path of a relatively nearby gamma-ray burst, it could eliminate all life. Given that life has existed on the earth for quite some time, the 'Lindy effect' suggests that the sum of these presumably-constant risks is small. We are much more likely to become extinct due to an anthropogenic cause.
A gamma ray burst is one of the possible hypotheses for the cause of the Ordovician mass extinction event, one of 5 big ones Earth has had. No idea why the Great Oxidation Event isn't included there as it was also one of the deadliest mass extinction events - plants and their vile poisonous oxygen killing off basically everything else.
So I don't think the 'Lindy Effect' would apply as species are mostly perishable, just on longer timeframes. Humanity is hopefully the exception, but absence of evidence of other advanced intelligences in the universe doesn't paint the most promising picture there either. On the other hand we're already on the cusp of colonizing other planets and once that process begins the odds of humanity ever going extinct will approach zero. On the other hand at greater distances "humanity" will likely splinter fairly quickly (relative to on a geologic or even species survival timeline) into numerous distinct species.
No, not me anyway. we are all floating (falling) in the (nigh) void of space (equally) alone ... which is great protection from all the monsters everywhere!
Deliberately hitting things in space is hard, accidentally, more-so.
Consider the chance of our sun getting whacked when the entire Andromeda galaxy gets here ... billions or more likely trillions to one. The chance of a single mass in our own galaxy getting us should be less than that.
edit: as far as I know the only difference between getting gobbled by a black hole v.s. anything else is our atoms won't get to continue their evolution into larger atoms in this universe. (or maybe see it as our atoms get to complete their evolution in this universe)
I'm trying to picture intersecting paths though. Does a faster moving black hole cause more or less damage to a target?
Imagine a black hole on the quite small end, intersecting the core of a planet. Unlike regular matter, it can't really produce bow shock through collisions, right? All the target matter in the direct path just "falls in" and in elastically reduces the black hole momentum a tiny bit?
Some matter outside the direct path could be accelerated towards the black hole but slingshot behind it, rather than into it. So this material could produce an impressive wake, with material spraying outward from the collision path and interacting with the remainder of the target.
But, all this visible chaos comes from gravity rather than more direct kinetic interactions, right? If the black hole is moving faster, doesn't the target's material gets less gravitational acceleration as it spends less time in the near field? So, if the blackhole is moving very fast, does it bore a smaller hole and have less interaction with the target? Or do other effects of relativity make this more convoluted to think about?
I'm imagining a cylindrical plug of a planet "instantaneously" disappearing, and then the remainder of the planet collapsing inward to fill the void, bouncing off itself, and ringing like a bell.
> Does a faster moving black hole cause more or less damage to a target?
When a black hole accretes matter, the matter can create tremendous radiation before it crosses the event horizon due to the atoms experiencing many effects such as rapid nuclear fusion and becoming new forms of matter such as neutronium. The precise amount of energy released depends on spin, charge, and size of the black hole, and the speed at which the matter approaches the black hole.
If a tiny black hole (Let's say 10cm across) ripped through the earth at significant speed it would be like the center of the planet momentarily became the center of a star and (hand waving a bunch of assumptions) the total energy could easily be greater than the gravitational binding energy of the planet. The planet would explode.
I don't. If the sun were replaced by a black hole of equal mass next Tuesday at noon, the only thing we would notice is that it suddenly got very dark and very cold. We would continue orbiting the thing while freezing to death over the next few days.
It's really, really hard to fire something into the Sun. We can't do it. The same goes for black holes. Things don't just get sucked in. They usually end up in orbit instead.
> It's really, really hard to fire something into the Sun.
It's hard if you aim at the Sun. So don't do that.
You just have to kill your starting orbital velocity relative to the Sun (the efficient way is to fly away out from Earth to higher orbit and then kill your orbital velocity rather than just immediately killing the orbital velocity you get from Earth at Earth's orbital distance -- we can launch craft with enough delta-V to do the former, but not quite the latter, IIRC, with current technology.
> Things don't just get sucked in.
They do unless they have a sufficient component of their velocity at right angles to the Sun to avoid doing that, but that's a solvable problem. You don't hit the Sun (easily) by thrust at the Sun, you hit it by thrusting at right angles to it, in the direction opposite whatever component of velocity you currently have orthogonal to the Sun, and gravity will take care of the rest.
(1) We can launch a rocket that has a payload that hits the sun: it's just costly to do because the rocket starts out orbiting the sun, so we would have to expend delta-v to neutralize the tangential component of the initial velocity.
(2) If you are in a space ship heading towards the sun, it is easy to hit the sun as long as you can steer, and even if you can't steer, if you are heading squarely at it and no planet gets near you to change your velocity, you will hit it.
"You are missing the point" counts as a swipe in the sense that the HN guidelines are using the term. Please edit them out in the future. They just add acid to the threads, and you don't need them.
Looking over account histories is standard moderation; of course we do that.
It's a fairly benign sentence selected as the worst thing in my post history due to a witch hunt because I posted a completely unbiased summary of events that was interpreted as right-leaning.
Literally, until just now (checking your comment history to see if possibly we had interacted elsewhere that I had forgotten), I hadn't seen or read any of your posts outside of this thread.
Not sure how you got from me responding to two of your posts in this thread that I was "targeting" you for something in some other thread.
The size of the black hole described in the paper is ~ 20 km, so it is tiny. Even we have millions of such objects (and most likely we do), the chance of hitting something, given the enormous size of the galaxy is negligible.
The black hole in the paper is also ~7 solar masses. If that passed between the Earth and the Moon it would rip apart the earth from just the tidal forces.
