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Gravitational Currents Could Slash Fuel Needed For Space Flight
Hugh Pickens writes "BBC reports that scientists are mapping the gravitational corridors created from the complex interplay of attractive forces between planets and moons that can be used to cut the cost of journeys in space. 'Basically the idea is there are low energy pathways winding between planets and moons that would slash the amount of fuel needed to explore the solar system,' says Professor Shane Ross from Virginia Tech. 'These are free-fall pathways in space around and between gravitational bodies. Instead of falling down, like you do on Earth, you fall along these tubes.' The pathways connect Lagrange points where gravitational forces balance out. Depicted by computer graphics, the pathways look like strands of spaghetti that wrap around planetary bodies and snake between them. 'If you're in a parking orbit round the Earth, and one of them intersects your trajectory, you just need enough fuel to change your velocity and now you're on a new trajectory that is free,' says Ross. 'You could travel between the moons of Jupiter essentially for free. All you need is a little bit of fuel to do course corrections.' The Genesis spacecraft used gravitational pathways that allowed the amount of fuel carried by the probe to be cut 10-fold, but the trade off is time. While it would take a few months to get around the Jovian moon system using gravitational currents (PDF), attempting to get a free ride from Earth to Mars on the currents might take thousands of years."
We can connect them to the Theodore Fulton Stevens Internet.
Space Travel is just like the internet. All you need to do is navigate a bunch of tubes.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
For example, this old article discusses the same concept.
Anyone else reminded of the Anderson drive?
End of lesson. You may press the button.
In my day we went to Mars uphill both ways unlike you kids who coast the whole way - and we LIKED IT!!!
Next:$150 trip to Mars
Come on MIT boys, pump up that balloon and add another handwarmer.
... Jovian moon system suing gravitational currents ...
Where do you find a law firm that can sue a gravitational current?
While it would take a few months to get round the Jovian moon system suing gravitational currents (PDF)...
I had never before considered using the power of lawsuits to drive an inter-planetary vehicle, very interesting. But is it feasible? What's the TPL (thrust per lawsuit) against a given gravitational current and how many lawsuits can a lawyer put out during the life of a mission? Does the size of the gravitational current matter? I imagine so since they said the system is much faster suing Jupiter's gravitational currents than Earth's and Mars' currents.
I haven't seen any solid details on this yet, I think this whole plan is still a ways off yet.
Security is mostly a superstition... Avoiding danger is no safer in the long run than outright exposure. - Helen Keller
routeofages - Tag when you need one?
Apparently the Rocket Industry Association of America found out that people were planning to travel for free by stealing gravity from nearby planets. They also discovered that gravitational currents are aiding and abetting these crimes by making it easy to find and use the gravity. These pirates think they can escape prosecution by relocating to the Jovian moon system, but the RIAA lawyers were able to track them down and sue them within a few months.
The vast majority of fuel usage is simply getting out of orbit. I imagine this would be musch more useful for vehicles that are simply motoring around the solar system, but not dropping to the planet, or even going into LEO.
Wow!
What a memory!
This is a great idea but the difficulty is in solving n-body problems incorporating all the gravitational bodies in the solar system.
Even finding the Lagrange points between the earth, sun, and moon is very difficult. Throw in all the other moons and planets and you have a even harder task on your hands.
This is a popular method in anime.
I saw a show once that demod two spining bicycle wheels at right angles lifting of the ground. It works off the right-hand rule - the sideways spin feeds the other and it feds back in. its not perpetual motion but its some way of cheating where you go faster and faster. they theorized you could get to jup in a few weeks! anybody know this?
This was called the slingshot effect.
But TFA makes it sound like you can find 'just the right spot just past the Moon' and zoooooop! Off you go the the gasoline seas of Titan.
BS.
Douglas Adams stated that "Space if really big." The image in TFA makes it looks like a skate park. Try drawing the Solar System to scale, and you begin to get the idea. A local community college has a scale MODEL. The sun is about a meter in diameter a frisbee throw away is Earth, this tiny dot with a tinier a fly's wingspan away. It took us a Saturn V to get there and 4 days. TFA wants us to think that once we get there, we can "freefall [down] pathways in space around and between gravitational bodies. Instead of falling down, like you do on Earth, you fall along these tubes." That's crap, without a metric a55load of Delta V.
'If you're in a parking orbit round the Earth, and one of them intersects your trajectory, you just need enough fuel to change your velocity and now you're on a new trajectory that is free.''
BS.
We slingshot Apollo.
We wait for the planets to align and fling out our satellites, skipping them like stones over several planetary gravity wells to reach their destinations.
Now, I can go back to sleep
I swear to God...I swear to God! That is NOT how you treat your human!
Using Ed Belbruno's techniques, Japan sent a mission to the Moon.
http://en.wikipedia.org/wiki/Hiten
http://www.maa.org/news/042909belbruno.html
This is not new. Almost every mission going further away than Mars or Venus uses these gravity assists, and has since Mariner 10 (1974).
I really dislike the term "gravitational currents." It conveys exactly the wrong impression. The effects of 3rd bodies is almost negligable except during close approaches, so "gravitational billiards" would be much more appropriate.
Does this work the other way around?
1. Take a craft that has the fuel and thrust to go from Earth to Mars without the tubes in X days.
2. Actively navigate the tubes instead of free-falling
3. Wouldn't this make for a shorter, more efficient trip?
4. Does navigating the currents have any effect on relativity? (Could a ship travel closer to c through these tubes?)
I heard this suggested as an easier way to get to Mars and back: don't stop.
Rocket to Mars. Stay in high orbit. Drop some remote control vehicles to the surface. Operate them manually without the long delays that Earth-based controllers would suffer. Recapture some very small sample return vehicles from the surface. And shift back into a cheap return-to-Earth trajectory.
I think it's an awful lot of trouble just for more responsive remote controls. But it could be a big savings of fuel/mass and might be a wise step ahead of a full Man-on-Mars mission.
Pffft, Russians do it for $40, and survive more.
Table-ized A.I.
" attempting to get a free ride from Earth to Mars on the currents might take thousands of years." Is the fuel savings really worth getting there after the human race is extinct? I say put the petal to the metal. Run those hippies in their gravitational pathway mobiles right off the space highway. And tell them to take a shower.
Quote: Mars will be even tougher, these models suggest. Some scenarios call for missions that would last 18 months or more. "Right now there's no design solution to stay within safety limits for such a Mars mission," Cucinotta says. "Putting enough radiation shielding around a spacecraft would make it far too heavy to launch, so we need to find better lightweight shielding materials, and we probably need to develop medical techniques to counteract damage to cells caused by cosmic rays." He notes that one of the biggest obstacles to progress in this area is "uncertainty in the types of cell damage deep cosmic ray exposure can cause. We still have a lot to learn."
Source: http://science.nasa.gov/headlines/y2009/27may_phantomtorso.htm?list776758
A universe was sent to me by my staff last friday, I GOT IT YESTERDAY!
If you gravitate a whole moon at the time the gravitational waves are gonna get filled and when they're filled the universe is gonna be delayed!
If you quote this signature there'll be 72 copies of Windows ME waiting for you in Heaven.
I would be curious to know what reference frame they are hoping to use to generate these paths. I suppose it makes the most sense to do the mapping in a sun centered system but even then things are going to be changing a lot. The primary problem with trying to map the gravitational current paths between the LaGrange points of celestial bodies seems like it would be a time issue. The planets do not stay in the same orientation with respect to each other throughout any given amount of time. They are constantly shifting with respect to one another. As such, the gravitational current paths that the article discusses are also morphing and changing.
I would think that the best way to make use of gravitational currents would be to consider it as a design option for a particular mission and factor it into various trade studies against fuel and what not. This would allow the designers to decide if a particular mission would benefit from the current paths that exist at that particular mission time. Otherwise, collecting and aggregating all of the data to map these tubes for any particular orientation of the solar system seems like a very large task. I wouldn't particularly be interested in sifting through that data as a job. I feel sorry for the grad students that get that project as their theses.
Of course, if they are only planning on mapping the LaGrange orientations with respect to Sun-body systems the task would be greatly simplified. Limiting the task to the gravitational perturbations between the 8 planets + Pluto and the Sun would greatly reduce the orientation permutations needed to be taken into account. Approached from that regard, local LaGrange systems (e.g. the Jovian moons wrt to Jupiter proper) could be modeled separately and, thus, a series of local maps could be made for various moon-planet orientations at different times.
The task being described is certainly no walk in the park and I wish the article had more details relating to the scope of the project and the approach being taken. Drawing 'maps' for space is a very difficult problem because things don't hold still in space. There are very few inertial points of reference with respect to any given field of scope which can be mapped against.
Good luck to the team though...
Motorcycles, Robots, Space Gossip and More!
Like fish in the water, we are swimming in an immense sea of energetic particles but we can't see it. An analysis of the causality of motion leads to the inevitable conclusion that we are moving in an immense sea of energetic particles. Soon we will understand how to tap into the sea for energy production and extremely fast transportation. It will be an age where vehicles have no need of wheels, move silently at enormous speeds with no visible means of propulsion and negotiate right-angle turns without slowing down. Get ready for interesting times ahead because Aristotle was right about motion requiring a cause.
The Problem with Motion
Build it in smaller pieces and then put the vehicle together in orbit.
;-)
What? No! I didn't get the idea from watching Star-Trek movies. I'm just smarter than all the guys at NASA.
That was exactly what I took away from the article, too.
A work that expires before its copyright never enters the public domain and thus enjoys eternal copyright protection.
We can't even successfully navigate the cosmos but we're worried about fuel efficiency. Get to the edge of the solar system and back and then we can talk about light years per gallon.
Ok, so for the next planet the ship must be here for 3 years, and the next one stay there for other 14. This kind of trip could seriously cut the fuel needed for a mission, but maybe raise a lot the time for it, till the moment the planets are in the right position. The tech could be here today, but the launch must be delayed till next century.
Is there a reason we don't fly up to 30,000 ft and then turn the rockets on and go the rest of the way? It seems like a lot of fuel is wasted going straight up when we could use the air in the atmosphere to "fly" up at least part of the way. Maybe get a good % decrease in fuel? (I would think even 5% or 10% would be significant)
I'm sure there are good reasons, but as a lay person watching a shuttle launch it seems like a waste of energy just "brute forcing" our way off the planet.
As far as these gravitational currents, does this mean I should only weighing myself when there is full moon over my house?
"Depicted by computer graphics, the pathways look like strands of spaghetti that wrap around planetary bodies(meatballs) and snake between them."
This is a direct proof of the existence of the Flying Spaghetti Monster creator of the Universe(and a midget).
Big deal.
Gravitational assist orbits are known from the dawn of space time.
It helps and guess what, yes all the probes that were sent to mars do take advantage of such orbits.
Problem is that first, this doesn't help much, and second that vastly increases travel time, thus unsuitable for manned flight.
Linux forever
Regrettably, they've gone the way of the GNAA and the 'unprecedented evile' guy.
By this same logic, when our sun lines up with the plane of the milky way at 11:11am on Dec 21st, 2012, we should beware the tunnel of gravity that suddenly hits us. By the same logic that allows these gravitational tubes to exist, it makes complete sense that we should fear that 26,000 year occurrence. Who knows what will happen when we face that.
The BBC is not the Daily Telegraph
Drill baby drill - on Mars
The clue is in the "telegraph.co.uk" URL, idiot.
Mentioning the words Fuel and Space Flight in the same phrase shows how stone-henge we still really are.
If space flight is to have any future, nothing like "fuel" should still be used for it. Nasa or whoever, get a grip, sooner rather than later, thank you.
10-fold is 2^10 not just one order of magnitude.
Now if we only had a book to tell us how to use these unsecured cargo bays to get around the Galaxy...
HA! I just wasted some of your bandwidth with a frivolous sig!
lagrange points or something similar
Connect our space-elevator to a tube and off we go...
A gravity assist trajectory is using the gravitational field of a large planet to divert a spacecraft to it's final destination. Since you are falling down a gravity well with this trajectory, you generate acceleration. The reason this works is that you are essentially "stealing" some of the momentum from the planet (think billiard balls colliding and exchanging momentum, but this is just without the collision).
This technique is almost the dual of the gravity assist in that it has the spacecraft follow the 3 dimensional paths of zero-net gravitational acceleration. Think of this like walking between two mountains mostly along the isolines (instead of taking a path where you are walking down into a valley and have to walk back up). The path might be long and windy to walk across the iso lines, but you reduce the total energy you have to expend (except to get from your starting point to the iso-line and from the iso-line to your destination). The reason these paths are called currents is that it really isn't a 2-d isopath with minimum energy you are following, but really a 6-d iso path (position and velocity thus a "current"). This is where the analogy breaks down with the 2d isopath.
BTW, this is really, really old news... http://www.jpl.nasa.gov/releases/2002/release_2002_147.html
And also a DUPE http://science.slashdot.org/article.pl?sid=03/03/07/215211&mode=thread&tid=160
Well with the research into antigravity, and yes levitating a mouse... I'm sure some enterprising individual can figure out how to "amp" up the localized power of the gravitational currents until our cruise time to Mars is drastically less... of course that won't be for free... it would take a huge energy output, but something more efficient than thrusters I imagine... Now imagine finding gravitational currents to other solar systems.
Mark Anthony Collins
We're already making use of the Lagrange points that from the basis for this. The Wilkinson Microwave Anisotropy Probe (WMAP) sits at L2 more than 1,000,000Km away and the successor to Hubble, the James Webb Space Telescope is going there too. This earlier article has a few more details on the science; Why future astronauts may be sent to 'gravity holes'.
Rocket propulsion technology belongs in the Smithsonian right next to the buggy whip and the slide rule. It hurts just to think about it. What is needed is a clean technology that taps into the universal sea of energy in which we move for extremely fast transportation. Earth to Mars in hours instead of years, that sort of thing.
Essentially, physicists are wrong in thinking that motion does not require a cause. Acausal motion is crackpottery, on a par with the flat earth hypothesis. An analysis of the causality of motion leads to the inevitable conclusion that we are moving in an immense sea of energetic particles organized as a lattice.
The Problem With Motion
you just need enough fuel to change your velocity
Well, now, that's always the trick, isn't it? Sort of like, "you just need to pedal fast enough and you can fly the Gossamar Albatross".
I already carped about the reporting that makes this seem fast, easy and fun. http://science.slashdot.org/comments.pl?sid=1372627&cid=29455133
Here's your analogy:
Imagine a bobsled run made of ice. Ok, but the bobsled has no steering and follows the curves when the gravity balances the centripetal acceleration (oft called centrifugal force). This is not new. It's like driving on a banked, icy road.
OK, the run was designed to work because of a very specific initial speed. Anything higher, you fly off. Any lower and you slip down. The same with these chaotic trajectories. If you hit em too fast, you fly off the handle. They tried to use the surfing analogy, but we've ALL driven too fast on an icy road.
What you thought you heard from TFA was that there was a wall which would keep you in as you went faster. There ain't one.
Pffft, Russians do it for $40, and survive more.
Well, $40, yeah, but 'survive more', not so sure. Plus if you DO fail, or your political clout goes south, you could be erased from history. Not worth it to save $110, especially for current values of US $110.
The "tubes" are really iso-paths in 6-dimensional (3d position + 3d velocity).
The "tubes" happen to connect the LaGrange points in 4d, though.
You do NOT have to navigate spacetime in your own power if you stay in these "tubes", although since they are 6-d isopaths, their "minimum energy" aspect to the path is really at their intrinsic velocity (which is why they are slow).
Let's try to get this one right...
Good, fast, cheap; pick any two.
... and if you are wondering how to do space flight fast and cheap, just ask. I have a few nice bridges for sale too.
If I have seen further it is by stealing the Intellectual Property of giants.
As Burdell said, it's not a matter of altitude for the most part, it's velocity. So, consider a cannon on a tall mountain. The cannon functions just like a rocket, except all of the fuel is burned right at launch, providing a fixed amount of acceleration. Say you put a unit of propellant in the cannon (gunpowder, C-4, rapidly heated liquid Nitrogen, anything exothermic) and you find your projectile (cannonball, shell, capsule, Sputnik) will follow a parabolic arc, landing some distance away. However, consider if the Earth's surface didn't stop it, and the projectile passed ghostlike (or passed through a ghostlike planet). It would follow a elliptical path down, passing some distance from the Earth's center of mass, and then back up, to collide with your cannon. Okay, if you fire this cannon with successively larger amounts of power, the shell impacts the Earth's surface (also called 'landing' or 'Lithobraking') further down range. Eventually the shell is landing at spots over the horizon. And with enough power it will hit the back of your cannon. If you moved the cannon out of the way (and assuming they there are no mountains/buildings in the projectile's path) it would circle the Earth. This is an orbit--falling down with enough sideways velocity that you don't hit the ground. Now the nice little picture I just gave you of mountains, cannons and projectiles is ignoring the Earth's atmosphere. An object passing through the atmosphere experiences drag--slowing it down. So to launch a object into orbit we need to both, have enough change in velocity (delta-v) to go fast enough to not hit the Earth, and to push through the Earth's atmosphere, and fight gravity losses (because Gravity is pulling you down at 9.8 m/s^2 as you are going up.). Orbital velocity for an altitude of about 300 km is about 7500m/s, an you have to add about 1500â"2000 m/s for gravity/atmospheric drag losses. If you happen to use a PC, and some flavor of windows, try Orbitersim (http://www.orbitersim.com). It's a free spaceflight sim. Just take the exercise to get into Orbit and more will be clear to you Also, launching from a high altitude--good Idea, hard to do in practice for a larger rocket, as you have to either build a launch site on top of a very large, remote peak, or suspend a rocket from a balloon (limited payload), or an aircraft (also limited payload--see the Pegasus launcher)
Here's an article on this that is a bit more technical.
To borrow a computer term, 'massively parallel', consider the 'n body problem' (down the page a bit at http://en.wikipedia.org/wiki/Three-body_problem where the number of interactions is enormous, and all the bodies are in motion, making that enormous complexity change constantly in orientations and even numbers. computing this collection of interactions is typically done statistically since the calculations for the actual interactions would strain most computers.
Then consider the gravitational balance points created between every pair of bodies in the system. Those points are not gravity wells as are the bodies. Rather they are either gravity 'hills' where things fall away, or gravity 'saddles' where things fall away in one orientation and fall in perpendicular to it. These points are always on motion with the pair. Many are also changing in strength constantly due to changing distances (the Lagrange points are a special case of these balance points where one body orbits another that remains relatively stationary).
Then consider the balance points that come into being, move around, and go away due to interactions between each collection of 3 out the n bodies. And then each 4 bodies. And so on up to n. The interactions between the balance points don't create more since they're not gravity wells, but they can cross each other or come close enough to significantly alter each other including cancel out.
And ALL of this stuff is in motion. BBC says they're "mapping" the paths between all these? Bull. They're mapping (ie. predicting, because of the motion) a subset of the bodies and balance points. We used the sun/earth/moon system as an example of complex dynamics in a class at the Santa Fe Institute, and that was a bitch of a problem. The interactions between the sun and two bodies in orbit around it but not each other, say Jupiter and Saturn, create balance points in the orbital plane but constantly changing distance from the sun. I was never able to figure out whether the entire solar system including moons was an NP problem or not, but it damn sure looks like one.
Rather than try to create some long term ephemeris on these paths, which would take longer than it'd take to make the trip itself. Far better to plot the next best path to its end, then while traversing plot the next, and so on. The solution they're working on isn't intended to be a map, it's a proof of the complexity and of for providing an estimation of the travel times. And in the end it may be entirely academic, since the travel times involved mostly are in the range of significant probability that we'll lose interest in the vehicle's fate, we'll go extinct, or we'll develop a means of travel that'd make sending things this long, slow way as obsolete as the data that would have been returned.
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
I guess this is why Han Solo could do the Kessel run in less than 12 parsecs?
Glad to see another news story about this fascinating concept not covered in the press. But since it is obviously a story that is some years old you should credit the discoverer of the superhighway, Martin Lo, whose calculations for a halo orbit around solar lagrange point IIRC made possible the GENESIS mission.
It would be very cool if someone could comprehend the math involved and make a simulation of how it would look in the solar system. I don't understand if it is the multibody problem but have an unwarranted idea that a very rough approximation could be done on a modern PC. Haven't actually ever seen a diagram of such paths.
Should remember they are supposedly near to energy free and very slow. I remember posting on slashdot maybe a year ago about this in fact. It would be useful for creating a solar system wide IP network covering sensors that would report on observations of objects for NEO spaceguard and perhaps for astronomy too.
Actually, that was a typo in the manual of the sales demo. If you read the errata on the product you bought, you'll see that the word is "colonic".
Of course space is a series of tubes too. How else do you think we got Interplanetary Internet on the ISS?
How could we really know what those effects are going to be, without being able to measure them with real live instruments.
So far we cant even get to the moon again, and they are trying to convince us that there are these streams that we can surf to help us use less fuel out there...well get out there first to then have real proof before you can talk about it to the public.
I do agree to a certain extent that gravity from the planets will be less in those tubes, and you can ride the wave, but will it be such a fuel saver as we think, I am not sure, we might use more fuel trying to navigate them anyways, then just stick to the path we had from direct point a to point b, instead of snaking all the way around....
just my opinion.
Ironically you're right on. The orbital period for this story is 6 years.
BBC posts article in 2009, repeating Slashdot posting of 2003, which is actually rehashing something that was NEWS in 1997: http://en.wikipedia.org/wiki/Interplanetary_Transport_Network
(And you can see that the BBC, in a nice (circular?) demonstration of long-period orbital return, even USED THE IMAGE from the Wiki article from 12 years ago.)
I look forward to reading about this cool new calculation of low-energy orbital pathways again in 2015!
-Styopa
$40? You kiddin' me? Every self-respecting Russian has made it so Mars and back with nothing but a bottle of vodka and a pickle!
weinersmith
Ed Belbruno's work in the early 1990s on the Hiten lunar transfer orbit (see his book) predates Lo's IPS work. Belbruno's calculations saved the Hiten mission which failed to achieve lunar orbit using conventional trajectory planning. Lo generalized the concept to non-lunar missions throughout the solar system.
There are several helpful animations here
Professor Shane (series of tubes) Ross.... Has a nice ring to it:P
"I bow to no man" - Riddick