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Gravitational Currents Could Slash Fuel Needed For Space Flight

CmdrTaco posted more than 5 years ago | from the this-doesn't-smell-right dept.

Space 177

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."

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I know (0)

Anonymous Coward | more than 5 years ago | (#29454629)

We can connect them to the Theodore Fulton Stevens Internet.

So... (5, Funny)

jellomizer (103300) | more than 5 years ago | (#29454645)

Space Travel is just like the internet. All you need to do is navigate a bunch of tubes.

Re:So... (1)

Nadaka (224565) | more than 5 years ago | (#29454745)

Space Travel is just like the internet. All you need to do is navigate a bunch of tubes.

Get your facts strait man!

Its like a series of tubes, if you bunch them up, its just like bending a garden-hose.

The pressure from all the bits that cant get through might spring a leak!

Then you would have bits of bits all over the place.

Re:So... (4, Insightful)

Chris Burke (6130) | more than 5 years ago | (#29454749)

Space Travel is just like the internet. All you need to do is navigate a bunch of tubes.

Yeah, and you can get it for free as long as you're okay with it being slow.

Now we just need to find the Space Travel equivalent of your neighbor's unsecured wireless router, and we can even solve that problem!

Re:So... (4, Funny)

CarpetShark (865376) | more than 5 years ago | (#29455219)

Now we just need to find the Space Travel equivalent of your neighbor's unsecured wireless router, and we can even solve that problem!

I believe that would be an unsecured cargo bay.

Hello DentArthurDent (4, Funny)

TiggertheMad (556308) | more than 5 years ago | (#29456775)

Now if we only had a book to tell us how to use these unsecured cargo bays to get around the Galaxy...

Re:So... (1)

Tablizer (95088) | more than 5 years ago | (#29455383)

Space Travel is just like the internet. All you need to do is navigate a bunch of tubes.

Yeah, and you can get it for free as long as you're okay with it being slow.

and if you can tolerate all the pop-up adsteroids.

    -1 Stupid Pun

Re:So... (1)

CopaceticOpus (965603) | more than 5 years ago | (#29454823)

I can tell you this, space travel is not a dump truck!

Re:So... (1)

zerosomething (1353609) | more than 5 years ago | (#29454883)

but in this case we can run dump trucks through the tubes!

Re:So... (1)

KDR_11k (778916) | more than 5 years ago | (#29455129)

Rocket propelled dump trucks.

Re:So... (1)

Hellswaters (824112) | more than 5 years ago | (#29455517)

Space. Its not a empty-less void. Its a series of tubes.

We're Swimming in a Sea of Energy Right Now (3, Funny)

Anonymous Coward | more than 5 years ago | (#29455767)

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 [blogspot.com]

old idea (5, Informative)

jschen (1249578) | more than 5 years ago | (#29454675)

For example, this old article [slashdot.org] discusses the same concept.

Re:old idea (0, Redundant)

BenFenner (981342) | more than 5 years ago | (#29454849)

Not only that, but the Apollo missions heavily leveraged this concept in multiple ways, the most obvious was traveling around the moon instead of going straight to it, then straight back. Talk about old news.

Re:old idea (5, Informative)

Anonymous Coward | more than 5 years ago | (#29455485)

Or if you'd RTFA you'd see the part where they talk about the Apollo missions and how it is not the same concept.

dupe from 6 years ago (0)

Anonymous Coward | more than 5 years ago | (#29454867)

Wow!

What a memory!

Re:dupe from 6 years ago (1)

Tablizer (95088) | more than 5 years ago | (#29455257)

Isn't that link 2003? Or are you joking?

Re:dupe from 6 years ago (0)

Anonymous Coward | more than 5 years ago | (#29456471)

Isn't that link 2003? Or are you joking?

Linked article date: Sat Mar 08, 2003 @12:04 AM
This article date:Thu Sept 17, 2009 @12:17PM

So yeah 2009 - 2003 = dupe from 6 years ago
Unless you're Lt. Cmdr. Data, then it's 6 years, 176 days, 12 hours, and 13 minutes.

Re:dupe from 6 years ago (1)

jschen (1249578) | more than 5 years ago | (#29457163)

I don't actually remember the old discussion. But the concept of low energy transfers between Lagrange points is hardly new, and a quick Google search provided the aforementioned link.

Re:old idea (4, Funny)

Tablizer (95088) | more than 5 years ago | (#29455227)

There's also Dupe Currents, and if one knows how to correctly navigate them, they can avoid dupes.

But I think it's okay if Slashdot posts the same concept every 5 years or so. There is turnover in users. Woodstock is not a dupe if you missed the first one. (Then again, most Woodstock attendies were probably too strung out to remember the first one anyhow.)

   

Re:old idea (2, Insightful)

dpilot (134227) | more than 5 years ago | (#29455671)

As others have said, not news. In my deskPix directory, from which I randomly pick a background each login, I have "Interplanetary_Superhighway.jpg" dated Sept 8, 2005 which is as far as I can tell, exactly the same picture used in the article. Doesn't beat the 2003 Slashdot date, but the illustration matches.

Re:old idea (1)

johndiii (229824) | more than 5 years ago | (#29456001)

Not only that, but Asimov wrote about this in 1952 [wikipedia.org] !

Re:old idea (1)

Thanshin (1188877) | more than 5 years ago | (#29456225)

Not only that, but Asimov wrote about this in 1952!

Damn! 1952!

He must have a two digit uid at most!

Jerry Pournelle (1)

Verteiron (224042) | more than 5 years ago | (#29454685)

Anyone else reminded of the Anderson drive?

Re:Jerry Pournelle (1)

Verteiron (224042) | more than 5 years ago | (#29454827)

Alderson. ALDERSON. Clearly some re-reading is in order.

Re:Jerry Pournelle (1)

natehoy (1608657) | more than 5 years ago | (#29456989)

So the answer would be "No, no one has ever heard of the Anderson Drive" then... :)

In my day... (4, Funny)

sprior (249994) | more than 5 years ago | (#29454691)

In my day we went to Mars uphill both ways unlike you kids who coast the whole way - and we LIKED IT!!!

Re:In my day... (3, Funny)

Tablizer (95088) | more than 5 years ago | (#29455295)

"Damned space liberals, always looking for a free ride, sucking gravity right from the pockets of tax-paying Jupiter and the moon."

Next: $150 trip to Mars (2, Funny)

BigSlowTarget (325940) | more than 5 years ago | (#29454703)

Next:$150 trip to Mars
Come on MIT boys, pump up that balloon and add another handwarmer.

Re:Next: $150 trip to Mars (4, Funny)

Tablizer (95088) | more than 5 years ago | (#29455519)

Next:$150 trip to Mars. Come on MIT boys, pump up that balloon and add another handwarmer.

Pffft, Russians do it for $40, and survive more.
     

fracking lawyers theyre everywhere (2, Interesting)

ionix5891 (1228718) | more than 5 years ago | (#29454723)

... Jovian moon system suing gravitational currents ...

ted was a genius! (-1, Redundant)

Anonymous Coward | more than 5 years ago | (#29454735)

Space is a series of tubes too!

Typo (0)

Anonymous Coward | more than 5 years ago | (#29454747)

Where do you find a law firm that can sue a gravitational current?

Re:Typo (0)

Anonymous Coward | more than 5 years ago | (#29455945)

Everywhere. Just say you will pay the fees whether they win or lose.

Lawyers... IN SPACE!!! (4, Funny)

Bigjeff5 (1143585) | more than 5 years ago | (#29454771)

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.

Re:Lawyers... IN SPACE!!! (2, Funny)

jeffshoaf (611794) | more than 5 years ago | (#29455121)

What's the TPL (thrust per lawsuit) against a given gravitational current

DPL (Disgust Per Lawsuit) is even more powerful!

Re:Lawyers... IN SPACE!!! (1)

Stenchwarrior (1335051) | more than 5 years ago | (#29456303)

"Lawyers in Space"....they already did that [wikia.com] .

Re:Lawyers... IN SPACE!!! (1)

natehoy (1608657) | more than 5 years ago | (#29457059)

Given how many lawyers later become politicians, and how many sex scandals politicians seem to become embroiled in, I also wonder about the TPL (thrust per lawsuit).

Where's a... (0)

Anonymous Coward | more than 5 years ago | (#29454799)

routeofages - Tag when you need one?

suing the currents (5, Funny)

PTBarnum (233319) | more than 5 years ago | (#29454811)

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.

Re:suing the currents (1)

rarel (697734) | more than 5 years ago | (#29455199)

Unfortunately, the brief is currently travelling towards Mars where it will arrive in 2,237 years and two months. One of the clerks must have put a decimal point in the wrong place or something. A senior partner who asked to remain anonymous was quoted saying: "Shit, they always do that. They always mess up some mundane detail."

Getting out of Orbit (5, Informative)

moosetail (1635997) | more than 5 years ago | (#29454815)

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.

Re:Getting out of Orbit (5, Interesting)

Menkhaf (627996) | more than 5 years ago | (#29455397)

Which is why we need one of these: http://en.wikipedia.org/wiki/Launch_loop [wikipedia.org]

Have a look at the economics:

For a launch loop to be economically viable it would require customers with sufficiently large payload launch requirements.

Lofstrom estimates that an initial loop costing roughly $10 billion with a 1 year payback could launch 40,000 metric tons per year, and cut launch costs to $300/kg, or for $30 billion, with a larger power generation capacity, the loop would be capable of launching 6 million metric tons per year, and given a 5 year payback period, the costs for accessing space with a launch loop could be as low as $3/kg.[ http://launchloop.com/LaunchLoop?action=AttachFile&do=view&target=isdc2002loop.pdf [launchloop.com] ]

Re:Getting out of Orbit (2, Interesting)

DerekLyons (302214) | more than 5 years ago | (#29457073)

Have a look at the economics

I can't look at the economics - because there aren't any economics to looks at, only theories based on some questionable assumptions.
 
Like this one: The launch loop will, unlike any other significant project ever, come in at or under budget and at or under schedule. Or this one: That it will generate sufficient revenue in the first year(s) of operation to pay not only operating overhead, but also interest and principal. (Highly doubtful as there isn't any backlog of payloads sitting around waiting for launch - it will take years for the demand to build.)
 
Or the most questionable assumption of all: That it can actually be built and will operate as designed.

Mission to Mars (almost) (1)

AlpineR (32307) | more than 5 years ago | (#29455509)

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.

n-body problem (2, Insightful)

buback (144189) | more than 5 years ago | (#29454889)

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.

Re:n-body problem (-1, Troll)

Anonymous Coward | more than 5 years ago | (#29455281)

Uh, no, its not hard. A four year old could figure it out.

Re:n-body problem (4, Informative)

mbone (558574) | more than 5 years ago | (#29455409)

Depends on your time horizon. Millions of years, no. Human time horizons, however, we can handle.

A good, modern, numerical integrator at quadruple precision can handle the Sun, planets, and hundreds of asteroids with very small numerical errors (microns over decades). Bigger errors are introduced by observational uncertainty, primarily in the masses of the asteroids. But, even with that, errors are 100's of meters over decades.

Re:n-body problem (0)

Anonymous Coward | more than 5 years ago | (#29455541)

http://xkcd.com/613/

Re:n-body problem (1)

zrelativity (963547) | more than 5 years ago | (#29455881)

That's why god created engineers, and not mathematicians only to populate this blue planet ;-) **

What happened to Ninnle? (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#29454913)

It's been a long time since there were any Ninnle posts. Does Ninnle Labs still exist, or did it finally get taken over by Micro$oft?

Re:What happened to Ninnle? (0)

Anonymous Coward | more than 5 years ago | (#29456147)

Regrettably, they've gone the way of the GNAA and the 'unprecedented evile' guy.

Japanese (0)

Anonymous Coward | more than 5 years ago | (#29455057)

This is a popular method in anime.

get to jupiter in a few weeks (0, Troll)

Saint Stephen (19450) | more than 5 years ago | (#29455061)

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?

Re:get to jupiter in a few weeks (1)

flyingfsck (986395) | more than 5 years ago | (#29455341)

Sorry to burst your bubble, but someone had a thin nylon line somewhere...

Re:get to jupiter in a few weeks (1)

Tablizer (95088) | more than 5 years ago | (#29455477)

Sorry to burst your bubble, but someone had a thin nylon line somewhere...

Damn! There goes flying car plan #87. I'll never ever get one.

Hmmmm. Nylon wire? Orbital space tether? Plan #88 here I come! Jack is Back!
   

Back in my day... (0)

Anonymous Coward | more than 5 years ago | (#29455087)

This was called the slingshot effect.

You can't dumb down rocket science (4, Insightful)

starglider29a (719559) | more than 5 years ago | (#29455133)

TFA makes this sound really easy, cheap and quick. It's not. Can you decrease the propellant used to get from lunar orbit to Mars? Yes. Is it free and easy? No. But TFA says I can decrease the amount of propellant 10-fold! Yes, from 1000000 to 100000. If you use enough time (and money) a solar sail will get you there for free.

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.

Re:You can't dumb down rocket science (1)

justthisdude (779510) | more than 5 years ago | (#29455347)

Do you long to see the marvels of the Universe on less than 30 Altarian dollars a day?

.... Of course, there are ~10e6 of days travel just between here and Mars, so those Altarian dollars really start to add up....

Re:You can't dumb down rocket science (-1, Flamebait)

Anonymous Coward | more than 5 years ago | (#29455461)

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.

In order for this to make more sense you'd have to visualize space as a real fluid medium. Even though evidence continually points to this, we are still taught that space has no such medium.

Re:You can't dumb down rocket science (2, Funny)

geekoid (135745) | more than 5 years ago | (#29455559)

". Try drawing the Solar System to scale,"

I did, now get the hell off my map~

Re:You can't dumb down rocket science (1)

ceoyoyo (59147) | more than 5 years ago | (#29455871)

"If you use enough time (and money) a solar sail will get you there for free."

Any reasonable solar sail probably gets you there faster than the low fuel corridor anyway.

Re:You can't dumb down rocket science (2, Informative)

DarkSkiesAhead (562955) | more than 5 years ago | (#29456591)

starglider29a

TFA makes this sound really easy, cheap and quick.

From TFA

The trade off was time, he said. It would take a few months to get round the Jovian moon system.

Wouldn't that be the opposite of what you just said?

Re:You can't dumb down rocket science (1, Informative)

Anonymous Coward | more than 5 years ago | (#29456825)

If you actually read about this stuff, it's more or less the case. Nothing BS about it. The basic idea is that if you can get to one of the (unstable) Lagrange points (#1-3), only a very small impulse is needed to go anywhere in the solar system. It's a chaotic system where small changes to initial conditions will over time lead to an infinite range of outcomes. This has been known for decades, but is only now becoming somewhat practical as we have the computing power to calculate the trajectories.

It's only "somewhat" practical because the transfers can take impractical amounts of time, but the system has been used. In one case, a Japanese probe (Hiten) that was not designed with nearly enough fuel to get from Earth orbit to Lunar orbit was nevertheless salvaged for use as a Lunar probe (after their dedicated Lunar orbiter failed) by the way of an "Interplanetary Superhighway" or low energy transfer. It took six months to achieve Lunar orbit but practically no fuel.

Don't we always do it this way (0)

Anonymous Coward | more than 5 years ago | (#29455163)

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.

Summary says it all (3, Insightful)

GodfatherofSoul (174979) | more than 5 years ago | (#29455231)

...Earth to Mars on the currents might take thousands of years."

Now, I can go back to sleep

Wish I had mod points. (1)

maillemaker (924053) | more than 5 years ago | (#29455887)

That was exactly what I took away from the article, too.

They are just catching up with Ed Belbruno (0)

Anonymous Coward | more than 5 years ago | (#29455287)

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

The best ideas of the 1970's ! (3, Interesting)

mbone (558574) | more than 5 years ago | (#29455327)

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.

Re:The best ideas of the 1970's ! (0)

Anonymous Coward | more than 5 years ago | (#29455681)

This is not a gravity assist. RTFA.

Riding one of the gravitational currents was unlike exploiting the ''slingshot'' effect of a planet or moon's gravity, a routine space travel technique, he explained. ''It's not the same as a slingshot,'' said Prof Ross. ''Slingshots don't put you in orbit round a moon, whereas this does.''

Just one US mission so far has made use of the concept. The Genesis spacecraft was launched in 2004 to capture solar wind particles and return them to Earth. Following the gravitational pathways allowed the amount of fuel carried by the probe to be cut 10-fold.

Re:The best ideas of the 1970's ! (1)

Classic Guy (31424) | more than 5 years ago | (#29457109)

I really dislike the term "gravitational currents."

How about "gravitational thalweg"? It kind of fits.

http://en.wiktionary.org/wiki/thalweg [slashdot.org]

not gravity assist! (2, Informative)

slew (2918) | more than 5 years ago | (#29457183)

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 [nasa.gov]

And also a DUPE http://science.slashdot.org/article.pl?sid=03/03/07/215211&mode=thread&tid=160 [slashdot.org]

So if there was a 10-fold decrease (1, Interesting)

Whispers_in_the_dark (560817) | more than 5 years ago | (#29455429)

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?)

Re:So if there was a 10-fold decrease (2, Interesting)

ceoyoyo (59147) | more than 5 years ago | (#29455979)

Nope and nope.

It's just a low energy, weird looking, series of orbits. If you want to go to Jupiter, say, there are a couple of ways to do it. You can use lots of fuel and put yourself on a highly elliptical orbit of the sun then, when you're near Jupiter, use lots more fuel to kick yourself into orbit around it.

Or you can use less fuel to slowly spiral out to higher and higher Earth orbit, then maybe you kick into your own solar orbit, then maybe you wait until Mars is in the right place to kick you over into a higher solar orbit, then work your way over and get captured by Jupiter.

You can use various gravity slingshot maneuvers to help get you somewhere, which is what spacecraft have been doing since the first interplanetary probes, but if you don't want to wait around you can't use the "tubes." And they have no effect whatsoever on the laws of physics.

Re:So if there was a 10-fold decrease (3, Informative)

FooAtWFU (699187) | more than 5 years ago | (#29456103)

The "tubes" are unfortunately only "tubular" through four-dimensional spacetime. In three-dimensional space, they're just a spot (a LaGrange point) that moves around as the various bodies orbit. If you are trying to move faster than that, then you're essentially leaving the tube and entirely to navigate spacetime on your own power.

Stuck behind a Prius in the fast lane (0)

Anonymous Coward | more than 5 years ago | (#29455531)

" 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.

Manned Earth to Mars = Radiation Overdose (1)

BadEvilYoda (935532) | more than 5 years ago | (#29455625)

18 months is currently too long for a manned Mars mission, much less anything slower and therefore longer.

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 [nasa.gov]

Re:Manned Earth to Mars = Radiation Overdose (0)

Anonymous Coward | more than 5 years ago | (#29455843)

Naw, it's ok. I've got my tinfoil hat.

!= Radiation Overdose (1)

AmigaHeretic (991368) | more than 5 years ago | (#29455865)

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. ;-)

Re:Manned Earth to Mars = Radiation Overdose (1)

geekoid (135745) | more than 5 years ago | (#29456717)

"Putting enough radiation shielding around a spacecraft would make it far too heavy to launch,"

Or, launch it in pieces and assemble the shield in space.

Or, but a lot of water between you and the back,
Or, only heavily shield a smaller space.

Or take a nuclear power plant and creata a magnetic buble aounr the aft of the ship.

Or have two shits, one auto mated ship that stay between the lead ship and the sun.

It's an engineering problem; however pills that make people immune to radiation damage and repair them selves is very cool.
In fact the spin of technology from the technology would be huge.

Tubes! (1)

ZarathustraDK (1291688) | more than 5 years ago | (#29455651)

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!

Inertial Reference Frame? (1)

BJ_Covert_Action (1499847) | more than 5 years ago | (#29455747)

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...

Re:Inertial Reference Frame? (1)

Rocky (56404) | more than 5 years ago | (#29456571)

They probably a set of farthest (i.e., effectively immoble) stars to define the reference frame, like the Apollo missions did.

Hilarious... (0, Troll)

Last_Available_Usern (756093) | more than 5 years ago | (#29455899)

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.

Time travel (1)

gmuslera (3436) | more than 5 years ago | (#29455919)

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.

Fly part way. (1)

AmigaHeretic (991368) | more than 5 years ago | (#29456013)

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?

Re:Fly part way. (2, Informative)

Burdell (228580) | more than 5 years ago | (#29456557)

"Up" is not the problem in getting to space; it is the velocity that is the problem. A 747 can reach a top speed of 567 miles per hour, while orbital velocity is 17,500 miles per hour. So, even if you could make a 747 carry a fully-loaded shuttle (it can't), you'd still need to accelerate an additional 17,000 miles per hour (which would still require the solid rocket boosters and the external tank, which are the majority of the weight, which a 747 certainly couldn't carry).

The shuttle passes a speed of 567 miles per hour in the first 20-30 seconds of flight IIRC. They are already throtting back the engines by that point to reduce aerodynamic stress on the vehicle.

Re:Fly part way. (1)

AmigaHeretic (991368) | more than 5 years ago | (#29456913)

I was just thinking that maybe escape velocity would be less if you started at say 5-8 miles above the earth. But I'm sure I'm wrong. "If" that was the case, lower escape velocity and less distance to orbit, I was thinking that would mean less solid rocket booster weight. How we'd fly it up there etc etc of course I have no idea, but you're right probably not a 747. ;-)

All Hail FSM ! (0)

Anonymous Coward | more than 5 years ago | (#29456027)

"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).

This is sort of a groaner (2, Insightful)

Brett Buck (811747) | more than 5 years ago | (#29456099)

'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.

      Oy Vey! Of course I haven't RTFA (will later, being a space guy and all). But 'all you have to do is change your velocity'? That's exactly the same as what you do *without* gravitational currents. If you are in a parking orbit around Earth, and change your velocity by 13000 FPS, yes, you don't have to expend any more fuel to get to Jupiter. Of course that maybe took 200,000 lbs of fuel, but otherwise it's free. It's like saying "all you have to do is buy General Motors, and you get Corvettes for free".

      It is probably just a matter of saving some fuel, but the quote is exceptionally misleading.

        Brett

Re:This is sort of a groaner (0)

Anonymous Coward | more than 5 years ago | (#29457013)

Only a groaner if you don't know what you're talking (groaning) about. The whole point is that if you're at the right place (an unstable LaGrangian point), you only need an infinitesimal change in velocity. The only limit is how precisely you can stationkeep and navigate. If your stationkeeping system was precise enough to park your spacecraft exactly on Sun-Earth L1 with zero velocity relative to it, you really could transfer to Jupiter by farting in a precisely correct direction and waiting a few decades.

Re:This is sort of a groaner (0)

Anonymous Coward | more than 5 years ago | (#29457135)

We did buy General Motors. Now where is my free Corvette?

Gravitational assist orbits (1)

mx_mx_mx (1625481) | more than 5 years ago | (#29456123)

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.

Beware The Dark Rift in the Milky Way (0, Troll)

curmudgeon99 (1040054) | more than 5 years ago | (#29456167)

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.

Point of order (1)

fiannaFailMan (702447) | more than 5 years ago | (#29456437)

The BBC is not the Daily Telegraph

That is NOT the bloody BBC! (0)

Anonymous Coward | more than 5 years ago | (#29456445)

The clue is in the "telegraph.co.uk" URL, idiot.

Nonsense (0)

Anonymous Coward | more than 5 years ago | (#29456599)

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 nitpick (0)

Anonymous Coward | more than 5 years ago | (#29456667)

10-fold is 2^10 not just one order of magnitude.

aka (0)

Anonymous Coward | more than 5 years ago | (#29456991)

lagrange points or something similar

Space elevator out a here (1)

cellurl (906920) | more than 5 years ago | (#29457083)

Connect our space-elevator to a tube and off we go...
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