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'Halo Drive' Would Use Black Holes To Power Spaceships (space.com)
A new study from researchers at Columbia University in New York suggests future spaceships could use black holes as powerful launch pads to explore the universe. The study "envisions firing laser beams that would curve around a black hole and come back with added energy to help propel a spacecraft to near the speed of light," reports Space.com. "Astronomers could look for signs that alien civilizations are using such a 'halo drive,' as the study dubs it, by seeing if pairs of black holes are merging more often than expected." From the report: Study author David Kipping, an astrophysicist at Columbia University in New York, came up with the idea of the halo drive through what he calls "the gamer's mindset." Using what he called a "halo drive" -- named for the ring of light it would create around a black hole -- Kipping found that even spaceships with the mass of Jupiter could achieve relativistic speeds. "A civilization could exploit black holes as galactic waypoints," he wrote in a study accepted by the Journal of the British Interplanetary Society and detailed online Feb. 28 in the arXiv preprint server.
The major drawback of a halo drive would be that "one has to travel to the nearest black hole," Kipping said. "It's akin to paying a one-time toll fee to ride the highway system. You have to pay some energy to reach the nearest access point, but after that, you can ride for free as a long as you like." The halo drive works only in close proximity to a black hole, at a distance of about five to 50 times the black hole's diameter. "This is why you have to travel to the nearest black hole first and [why you] can't simply do this across light-years of space," Kipping said. "We still first require a means to travel to nearby stars to ride the highway system. Kipping is now investigating ways to exploit other astronomical systems for relativistic flight. Such techniques "may not be quite as efficient or fast as the halo-drive approach, but these systems possess the deep energy reserves needed for these journeys," Kipping said.
The major drawback of a halo drive would be that "one has to travel to the nearest black hole," Kipping said. "It's akin to paying a one-time toll fee to ride the highway system. You have to pay some energy to reach the nearest access point, but after that, you can ride for free as a long as you like." The halo drive works only in close proximity to a black hole, at a distance of about five to 50 times the black hole's diameter. "This is why you have to travel to the nearest black hole first and [why you] can't simply do this across light-years of space," Kipping said. "We still first require a means to travel to nearby stars to ride the highway system. Kipping is now investigating ways to exploit other astronomical systems for relativistic flight. Such techniques "may not be quite as efficient or fast as the halo-drive approach, but these systems possess the deep energy reserves needed for these journeys," Kipping said.
Maybe at some point civilizations come across a promising technology (like black hole creation) and don't see some hidden danger until it is too late?
And it would take a lot of energy to make one
All you have to do is wait 6000 years until the light beams return from the nearest black hole.
"First they came for the slanderers and i said nothing."
Let me get this straight. Photons would be fired toward the periphery of a black hole, so that they'd slingshot around and come back... faster than light? What?
Corruption is convincing someone that the selfless ideal is the same as their selfish ideal.
If this actually worked well, wouldn't we see halos around plenty of black holes, since other space-faring civilizations would be using the technique? Presumably enough laser light would be scattered by gravitational lensing or turbulence or whatever to be visible from here.
Corruption is convincing someone that the selfless ideal is the same as their selfish ideal.
TFS doesn't say this, but the idea is to use spinning pairs of black holes. You shoot photons back, and by gravitational slingshot they come back with more energy, and they propel the vessel by hitting the sail.
Co-orbiting black holes, moving at relativistic speeds before their merger, are untapped batteries. There are an estimated 10 million black hole pairs in our galaxy.
It never ceases to amaze me at the amount of fantasy physics that occur in science. Take the classic "wormhole" concept where they fold a piece of paper and put pencil through it to imitate space being folded by phenomenon so that great distances can be traveled with little effort. It is entirely bunk, just like time, everyone knows it, but because they are enamored by the fantasy of it, they agree to it as a concept. Well here is a real physics check, collapsing that much volume (space is not actually empty) into a small space like that would become a black hole... and then you have your next problem... getting whatever mechanism that caused the collapse to un-collapse it, considering the nature of that phenomenon. Good luck with that madness. Same problem here... to drive a laser powerful enough to do what they are talking about likely means having enough power to accomplish the task in other ways. not to mention a few other important factors. Space is moving, things are bending, we cannot see what is on the other side, we cannot effectively predict where we will be when the beam comes back around... and finally... light is still too slow for that kind of effective use because of relativity. The light itself may speed up or slow down but our usage of it will drastically reduce its effectiveness, unless some other new technology like the EM drive were to be discovered. Right now.. its a bleeding fantasy.
Instead of calling it spacetime, it should be called Space and Energy. Time is nothing more than a conceptual tool we use to facilitate the measurement of Space and Energy as it changes in the reality we are able to grasp and observe.
Once you made it to the nearest black hole you can of course launch yourself in any direction, but if you ever want to change course you'll need to end up near another black hole. So this mode of transport basically involves aiming at a black hole over a distance of many, many light years, and then launching yourself almost directly at it. Don't forget to use your turn signal ;-)
Having said that, I'm in awe at the creativity that went into this.
There's a much bigger problem with this, and every other idea for accelerating to relativistic speeds: how the heck do you slow down? It takes just as much energy to slow down, but when you're traveling that fast you shoot past the next pair of black holes before they can reduce your speed anywhere near enough.
Same problem as a light sail, which might work for acceleration as you build up speed near the sun but can't possibly work for deceleration since it's going too fast to collect enough energy from the destination star before it's gone.
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I didn’t read the article, but since the energy described would result in very short wavelength photons, wouldn’t the just pass straight through any solar sail? https://science.nasa.gov/ems/1...
Just a few, teeny tiny problems:
1. So you need to be close to the black hole. Except for the very largest black holes, the tidal forces will rip you apart. See the answer to problem 3 in this exercise: solar mass black hole, distance roughly 30 times the radius, tidal forces on a human-sized object of 50,000g. Good luck with that.
2. Aside from that, they are relying on a "slingshot" effect for the laser beam. But the photons are already travelling at light speed, so they cannot speed up. They energy increase will go into frequency: you'll be transforming light into hard gamma radiation. Enough energy to accelerate you to relativistic speeds is more likely to simply vaporize your ship.
3. If you survive the tidal forces and the radiation and actually get to relativistic speeds, you're going to need to target another black hole to slow down, by reversing the whole process.
4. Meanwhile, you still have to travel interstellar distances by some other means, to get to and from the black holes.
This isn't science. It isn't even science fiction. Heck, I expect more realism in bad space opera.
Enjoy life! This is not a dress rehearsal.
I'm currently playing Elite dangerous and taking part in the Distant Worlds 2 expedition community event. 8 months across the Galaxy and back. 8 months.
And while I have an unrealistic space ship with a fictional "Frame Shift Drive" that can jump approx. 41 light years at a time after "collecting fuel" by flying around a sun at speeds faster than light for half a minute (just as unrealistic) I *still* need thousands of jumps and days to cover the radius of our Galaxy without stopping for vistas.
Frontier, the developers of Elite Dangerous, did some neat things in trying to be sort of scientifically correct with the representation of space and solar systems. And it has shown me one thing I wasn't fully aware of until now: the scales we're taking about when we talk about our solar system, our '''neighbor''' systems or let alone our Galaxy are so absolutely unbelievably big the words "large" or "huge" don't even fit in the faintest way.
Bottom line: I'm pretty sure somewhere out there civilizations exist, have existed and will exist. However, that we ever get to meet them or they us is, to be realistic, very very very unlikely. Like, I'd say, even orders of magnitude more unlikely that life and then intelligent life comes to exist in the first place. Life happens in extremely narrow margins at our scale as it is. That we get to change the laws of physics and get to travel around the system, Galaxy or even universe like we get to ride a bike is nice daydreaming, but it won't happen.
Not for us and not for others. It's pure physics and a game attempting to show the scale of our Galaxy can drive home the issue of scale and distances we're taking about.
We're alone and they are too. And it will stay that way until we fade.
My 2 cents.
We suffer more in our imagination than in reality. - Seneca
I hope it works out better.
---- The above post was generated by the Turing Institute. Maybe.
Small thinking mistake in this hypothesis,... Which life forms - or complex matter of any kind - is able to survive the gravitational pull at a distance of only 50 times the radius of a black hole?
I believe the Romulans have prior art
SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
That close to a black hole you get fantastic time dilation. After you move away, you find your whole civilization gone, or changed to something new.
How about we just start by building rockets and exploring the solar system a little bit before we start thinking about using black holes to get around space?
File under 'M' for 'Manic ranting'
What a bunch of thieves.
The concept of a "Black hole driven starship" is called the Kugelblitz engine.
https://en.wikipedia.org/wiki/...
Looking through the comments on a site *FOR NERDS* no one has brought this up yet. Shame.
"Not to mention all the idiots who use words like boxen."
Anonymous Coward on Monday August 04, @06:49PM
I've seen some misunderstandings in several posts that warrant correction at the top level.
Dealing with relativistic speeds is an engineering problem, and not necessarily a difficult (at least when compared with other challenges of interstellar travel) one.
https://phys.org/news/2018-09-...
Deceleration with light sails is a solved problem, at least on paper. I'm not aware of any deployed examples.
http://ffden-2.phys.uaf.edu/21...
Those people who think they know everything are a great annoyance to those of us who do. (Isaac Asimov)