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Nomad Planets: Stepping Stones To Interstellar Space?

Soulskill posted more than 2 years ago | from the cold-dark-rocks-make-good-stepping-stones dept.

Space 244

An anonymous reader writes "Ian O'Neill suggests in an opinion piece at Al Jazeera that brown dwarves and nomad planets (planets not orbiting any star) could be a much needed stepping stone on our way to foreign stars. Quoting the article: 'In February, a fascinating paper was published in the Monthly Notices of the Royal Astronomical Society detailing calculations on how many "nomad planets" the Milky Way must contain after estimating our galaxy's mass from how much gravity it exerts on surrounding space. Scientists from the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) had uncovered something surprising — there are likely many more planets in the Milky Way than stars. ... Louis Strigari and his Kavli team calculated that there must be 100,000 planets for every star in the Milky Way (PDF). That's a lot of planets! But how can this be? Every star can't have tens of thousands of planets ranging from Pluto-sized to Jupiter-sized. This planetary "excess" actually suggests the existence of planets that were born without a star — nomad planets. ... we need all the help we can get if we are to venture to another star, so these ultracool brown dwarfs could become much-needed "stepping stones" for future starships to refuel on their light-years of journey time. There may be the possibility that these sub-stellar objects may even become more desirable targets for interstellar travellers. After all, there may be dozens of these invisible objects between here and Proxima just waiting to be uncovered by the sophisticated infrared telescopes of the future; they'd certainly make for more accessible scientific curiosities.'"

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244 comments

Dark matter? (4, Interesting)

Anonymous Coward | more than 2 years ago | (#39345861)

Sounds like they're hypothesising that all the "dark matter" is actually made of planets, or did i miss something...

Also - frist prost!!!

Surprising? (1)

amicusNYCL (1538833) | more than 2 years ago | (#39345973)

Scientists from the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) had uncovered something surprising — there are likely many more planets in the Milky Way than stars.

Why is that surprising? Our own solar system contains at least 8 times more planets than stars.

Re:Surprising? (3, Interesting)

alienzed (732782) | more than 2 years ago | (#39346013)

It's surprising because this article claims there are 100,000 times more planets than stars, quite a ways off from 8x. Methinks we just don't know squat about physics on that level to make absurd estimations like this. I am not a physicist but so many theories being thrown around seem just as dense as the black hole at the center of our galaxy.

Re:Surprising? (5, Informative)

khallow (566160) | more than 2 years ago | (#39346107)

The estimate while not based on a lot of evidence, does have a rational basis. The authors are using a power law model and estimates of large nomads (objects above the mass of Jupiter through to brown dwarf mass) from microlensing events to give a crude estimate for the population of planets down to Pluto size. It's shaky, but not unreasonable given that asteroids follow the same power law distribution, for example.

Nomad Planets = Space Vehicles for Aliens? (2)

Taco Cowboy (5327) | more than 2 years ago | (#39346479)

If human of Planet Earth can think of nomad planets being vehicles to cruise the universe, you think sentient aliens from other planets wouldn't think of he same thing?

Perhaps they already are doing that

Too Bad (0)

Anonymous Coward | more than 2 years ago | (#39346633)

Too bad anyone attempting to reach them would go blind given the time it would take to traverse the distance and the rate at which human eyeballs deform in space.

Re:Surprising? (1)

Shavano (2541114) | more than 2 years ago | (#39346977)

Seem too low. The solar system contains only 8.2 planets. Why are so many planets in such a small volume of space?

No, baryonic matter (4, Insightful)

Roger W Moore (538166) | more than 2 years ago | (#39346003)

Sounds like they're hypothesising that all the "dark matter" is actually made of planets, or did i miss something...

DM cannot be made of planets because it cannot be made of atoms (it was not part of the plasma which filled the universe ~380k years after the Big Bang) nor does it have the same distribution as matter in a galaxy (rather than a disc it forms a spherical halo). The "gravitational effect" the summary misleading refers to is not the gravitational field of the galaxy but the local gravitational field of the object which bends light creating a lens effect. If the object passes between us and a distant star then the field will bend more light towards us causing the star to get brighter which is how you can detect them without seeing them.

Re:No, baryonic matter (0)

Anonymous Coward | more than 2 years ago | (#39346481)

The orbits of planets would not be constrained by the galactic plane. Given the probability of encountering the gravitational field of another star or planet, or even collision, then that would more than likely send things flying towards the galactic poles.

Re:No, baryonic matter (1)

Roger W Moore (538166) | more than 2 years ago | (#39347597)

The orbits of planets would not be constrained by the galactic plane.

Unless you have a spherical halo of Dark Matter which is what I understand you need to stabilize spiral galaxies otherwise they rapidly (on galactic timescales) turn into elliptical galaxies....at least according to an astrophysics talk I heard a couple of weeks ago.

Re:Dark matter? (4, Informative)

John Hasler (414242) | more than 2 years ago | (#39346151)

Sounds like they're hypothesising that all the "dark matter" is actually made of planets, or did i miss something...

You missed the fact that the total mass of all these little objects is negligible compared to the amount of dark matter that needs to be accounted for. You also missed the fact that "Maybe it's all cold baryonic matter!" was the first thing the physicists thought of but when they went through the calculations they could not make the numbers work out.

Re:Dark matter? (2)

swamp_ig (466489) | more than 2 years ago | (#39346671)

My understanding that MACHO (ie: brown dwarf and small planet) object dark matter has been pretty much ruled out by microlensing experiments. See http://en.wikipedia.org/wiki/MACHO [wikipedia.org] . Essentially if you stare at a distant star for long enough, you should see lots of gravitational microlensing (peaks in brightness) as all the small planets pass in front of the star.

Any hypothesised large amounts of dark matter would have to be fine tuned carefully to get around this data.

Re:Dark matter? (2)

mbone (558574) | more than 2 years ago | (#39347721)

No, they are not. There are nucleosynthesis limits [caltech.edu] that show that baryonic matter (us, stars, planets) are only a small fraction of the total dark matter (somewhere in the 4 to 10% range).

Now, there also is "missing" baryonic matter (about a 50% difference between what we can see and what nucleosynthesis indicates), so it must be part or even all of that. Note that stars etc are only about 10% of the baryonic matter, so I would be surprised if the planets were more than another 5% or 10% to that total, and thus maybe 1% to the total mass of the universe.

I'm not normally this racist, I swear. (5, Funny)

zill (1690130) | more than 2 years ago | (#39345873)

Al Jazeera that brown dwarves and nomad planets

I see what you did there.

Re:I'm not normally this racist, I swear. (-1)

Anonymous Coward | more than 2 years ago | (#39346031)

I'm not racist either. Not even a little teeny tiny bit at all.

So, when we find one of these nomad planets can we send all the niggers there? Pretty please? I am a level-headed guy so I am willing to compromise - how about just all the niggers in North America and let them keep Africa? I want to walk in an inner city and feel safe, dammit.

Re:I'm not normally this racist, I swear. (-1)

Anonymous Coward | more than 2 years ago | (#39346271)

Midgits with beer, hookers and noodly appendages.

FTFY

Re:I'm not normally this racist, I swear. (2)

M. Baranczak (726671) | more than 2 years ago | (#39347295)

Sometimes I wish there was a "+1, Troll" option.

Safety At A Price (1)

JohnPerkins (243021) | more than 2 years ago | (#39345875)

A most unusual planet...One million stars for the location...

light-years of journey time?? (4, Informative)

Anonymous Coward | more than 2 years ago | (#39345877)

When did a light year become a unit of time?

Re:light-years of journey time?? (4, Informative)

Anonymous Coward | more than 2 years ago | (#39346037)

When did a light year become a unit of time?

Ever since the Millenium Falcon made the Kessel Run in under 12 parsecs.

Re:light-years of journey time?? (2)

JohnPerkins (243021) | more than 2 years ago | (#39346135)

Han was lying.

http://starwars.wikia.com/wiki/Kessel_Run

Re:light-years of journey time?? (3, Funny)

Surt (22457) | more than 2 years ago | (#39346855)

It's a route optimization problem, sort of like traveling salesman. Getting the route done in less than 12 parsecs is really good.

You want to stop at this dwarf star? (5, Insightful)

Anonymous Coward | more than 2 years ago | (#39345911)

I don't think I'd want to stop at some random dwarf star. What is it you don't want on a long trip? Yes, to slow down and enter another gravity well. Doing so would make for a hell of a long trip. The time spent accelerating back along your path (people used to call it decelerating, but apparently that isn't a correct term), the fuel used escaping from the new gravity well, and the time and fuel used accelerating again. Worth it? Maybe if your design requires all that refueling. But the time involved is going to be the killer. It would probably triple (or more) the duration of the trip.

Re:You want to stop at this dwarf star? (4, Insightful)

Grishnakh (216268) | more than 2 years ago | (#39346017)

Yeah, I can't really think of how this would make sense either. You really shouldn't need a lot of fuel when you're in interstellar space, because you've already expended your fuel to build up velocity; you'll just need to keep half your fuel to slow down during the second half of the voyage. These aren't ocean ships here; there's little to no resistance in space, so your ship will continue at the same velocity until you start decelerating. Maybe they're worried about running out of supplies for the people on board (like with a generation ship), but betting your survival on some random brown dwarf or starless planet along the way having usable supplies (like water, oxygen, things to convert to food) seems rather idiotic; instead, you better have the technology for near-100% recycling of all the things humans need to survive, or not bother making the trip.

And who ever said "decelerating" isn't correct any more? The same person who thinks light-year is a unit of time?

Re:You want to stop at this dwarf star? (1)

betterunixthanunix (980855) | more than 2 years ago | (#39346253)

You really shouldn't need a lot of fuel when you're in interstellar space

You might need fuel to keep the passengers alive, and that is assuming that we even develop a power system that can provide power long enough to even reach such a planet.

Re:You want to stop at this dwarf star? (2)

KeensMustard (655606) | more than 2 years ago | (#39347681)

Any passenger that needs to be kept alive is too impractical for a journey such as that. Being alive implies dying, which means that the ship would need to be intergenerational. This introduces huge problems ethically. The only feasible approach is to send mechanical beings - these can be switched off and thus consume no power until they are needed, thus saving huge resources.

speed bumps (2)

tverbeek (457094) | more than 2 years ago | (#39346261)

<pedantry>In relativistic terms, what we call "deceleration" is simply "acceleration" with the opposite vector (i.e. the other direction).</pedantry>
It's absurd to say it's an "incorrect" term, though; we are allowed to have words for opposites, after all.

But yeah: stopping at a brown dwarf or other nomad planet on an interstellar journey makes even less sense than pulling off the expressway and stopping at a gas station to walk around, when you were going 80mph and had a full tank of fuel (i.e. momentum). If they were in the right place and massive enough, they could be worth targeting for a little gravity assist to accelerate a bit more, but what else could they possibly have that would be worth the huge expense in time and energy to stop at one? I'm sure they'd be fascinating enough to warrant exploration in their own right, but for interstellar travel, they'd be "speed bumps" not "stepping stones".

Re:speed bumps (1)

Grishnakh (216268) | more than 2 years ago | (#39346447)

In relativistic terms, what we call "deceleration" is simply "acceleration" with the opposite vector (i.e. the other direction).
It's absurd to say it's an "incorrect" term, though; we are allowed to have words for opposites, after all.

It seems to me that it's actually a more useful term. "Acceleration" just means you're accelerating; you have to use extra words to specify more information such as the direction. With "deceleration", you're combining the fact that you're accelerating, and the direction (the opposite vector of the current direction of travel), into a single convenient term.

Re:speed bumps (1)

ghostdoc (1235612) | more than 2 years ago | (#39346613)

Well, you could use them as slingshot accelerators, much as current interplanetary missions use the solar system's planets.

Which gives the slightly ridiculous possibility of interstellar travel being something like a vast game of snooker, slinging your craft around a few hundred nomad planets to build up speed then using a few hundred more to decelerate as you get close to your destination.

Re:speed bumps (1)

tverbeek (457094) | more than 2 years ago | (#39347287)

That's what I was talking about, using it for gravity assist.

And your snooker game is pretty much exactly how interplanetary probes get where they're going within the solar system.

Re:speed bumps (1)

Anonymous Coward | more than 2 years ago | (#39347469)

But they're useless for gravity assist. If you have a vehicle in interstellar flight, and you actually expect it to make it to the destination star before the vehicle falls apart from old age.. said vehicle will be traveling fast enough that the gravity assist of a non-stellar object will be effectively zero. And the non-stellar object would need to be pretty much on the way anyway, because at those speeds, the gravity well isn't going to significantly alter the vehicle's course either. And if you had the fuel to burn to bring the nose around, you'd be better off just boosting for the destination.

Re:speed bumps (1)

marcosdumay (620877) | more than 2 years ago | (#39346929)

Well, you could just walk around there for one generation or 50, while the newly aquired fuel lasts. Then you are nearer another star, and move.

Re:You want to stop at this dwarf star? (1)

DanielRavenNest (107550) | more than 2 years ago | (#39347141)

Accelerating and decelerating on an interstellar trip using only fuel you start with suffers from an exponential growth of fuel vs velocity. Look up the "Rocket Equation". If you send resupply robots ahead of the main ship, who mine these nomad objects and place fuel pellets or fuel tanks in your path so you can pick them up as you go, that turns an exponential fuel problem into a linear one. Yes, it takes work to accelerate fuel pellets, but less work than accelerating an entire ship with all it's cargo and passengers.

In a simplified version, imagine you use up all your fuel to accelerate to travel velocity, and then later pick up a new fuel supply to stop with. The second batch of fuel could come from a nomad.

Re:You want to stop at this dwarf star? (1)

Grishnakh (216268) | more than 2 years ago | (#39347693)

The big problem that I see with this is: how do you see these nomad objects, determine they have useful materials, and send resupply robots to them, before you've even launched your generation ship along that path? We have a hard enough time seeing exoplanets, and mainly see them because of their interaction with their parent star. How the heck are we going to detect nomad objects floating through interstellar space, and then figure out if they have any useful materials on them, without actually going there first?

Re:You want to stop at this dwarf star? (0)

Anonymous Coward | more than 2 years ago | (#39347507)

When I go on long trips, I kinda look forward to getting out once in a while to take a leak.
OTOH sometimes I go on a long trip and never leave the house. Truth be told, I have my doubts we'll get back to the moon in my remaining pathetic lifetime. See! it's happening again! My keyboard is melting. SHEILDS! SHEILDS!

Re:You want to stop at this dwarf star? (1)

Grishnakh (216268) | more than 2 years ago | (#39347735)

You only look forward to getting out because 1) your vehicle is small and cramped (it doesn't let you walk around inside), and 2) the outside is generally nice and has places where you can walk around and breathe fresh air.

Some random brown dwarf or other interstellar object isn't likely to have a nice grassy rest area with trees where you can walk around. However, your generation ship probably will have such things. You're not going to want to leave it, except maybe out of scientific curiosity (which is fine and well, except that there's probably much more interesting things in the star system you're traveling to, so it'd make more sense to send some robotic probes to any objects you pass by on your journey and get to your destination sooner).

Slingshot your main ship, get a snack on the way.l (0)

Anonymous Coward | more than 2 years ago | (#39346093)

Well, another possibility is that you have your high-mass ark-ship aimed at the nomad planet and it passes on a slingshot maneuver to point it towards a rendezvous with the next nomad in a travel chain.

Yes, it's slower than a direct-line trip (due to the zig-zag path) but there are some advantages:

1. You get a chance to send small nimble craft ahead to mine or siphon off a few things before rendezvousing with the main ship. Or even top off reserves from a permanent robotic installation. An "interestellar gas station", if you will.
2. Depending on the speeds gravitational gradient, and atmosphere and the tolerances of your equipment, it might even serve as a useful way to reverse course in an emergency. (Haven't done the math, might be improbable.)

Re:You want to stop at this dwarf star? (1)

ChrisMaple (607946) | more than 2 years ago | (#39346475)

There's the possibility that an interstellar object would have position and velocity appropriate to provide "slingshot" acceleration toward another goal, such as has been used for planetary exploration. My guess is it isn't likely.

Re:You want to stop at this dwarf star? (1)

osu-neko (2604) | more than 2 years ago | (#39347243)

I thought that kind of slingshot required the body to be in orbit, and the energy comes from degrading the object's orbit. I wouldn't think it would work using a free-floating object. I suppose, though, it's technically orbiting the galaxy... so maybe it would.

Re:You want to stop at this dwarf star? (1)

NemoinSpace (1118137) | more than 2 years ago | (#39347985)

Nah, it's mostly conservation of momentum. Although being able to predict where said object will be might come in handy. So like you supposed, it's probably orbiting something, but it doesn't have to be.

Re:You want to stop at this dwarf star? (1)

LesFerg (452838) | more than 2 years ago | (#39347833)

Actually my ship will have a force-field extending out half a light year ahead, which is incorporated into the mass-convertor. We won't need to slow down at all to pick a planet up for fuel. I heard some ethecists mention the need to stop and check for life forms but I'm not sure if they were going to be on board for the first trip.

Gravitational anomaly (2)

Hentes (2461350) | more than 2 years ago | (#39345947)

Galaxies having a gravity apparently bigger than their visible mass is not news, but that this effect is caused entirely by planets is unlikely. The extraordinary numbers they got are not "surprising results", but rather proof that their initial assumption was wrong. There ratio of heavy elements is too low for that many planets to form.

Freeman Dyson territory (2)

StefanJ (88986) | more than 2 years ago | (#39346047)

I don't have the essay collection on hand, but Freeman Dyson suggested something like this a long time ago. He imagined space-adapted life spreading through archipelagos of interstellar objects.

It might have been in the essay "The Greening of the Galaxy," in his collection Disturbing the Universe.

Re:Freeman Dyson territory (5, Interesting)

Araes (1177047) | more than 2 years ago | (#39346255)

A similar concept, the colonization of trans-neptunian objects [wikipedia.org] , and effectively colonizing in a ladder out of our star system and down into other ones by rock hopping is also quite old. Sagan and others were talking about this a long time ago.

Re:Freeman Dyson territory (1)

turkeyfish (950384) | more than 2 years ago | (#39346783)

So what, it would hardly matter since a human arriving at even the first "stepping stone" is likely be totally blind as a result of prolonged exposure to deep space, which causes severe permanent deformation of the human eyeball and degeneration of the optic nerve. This effect begins to occur on even much shorter trips, much less one into interstellar space. Dyson is a physicist, so its not surprising he doesn't know much about space biology.

Re:Freeman Dyson territory (2)

Surt (22457) | more than 2 years ago | (#39346901)

That effect is caused by living in microgravity, not exposure to deep space. We have the technology today to build ships that do not require the crew to live in microgravity.

Re:Freeman Dyson territory (0)

Anonymous Coward | more than 2 years ago | (#39347641)

Yeah, we can build it, doesn't mean we will unless you can convince our new Al Jazeera_Freemon Dyson worshiping_planet hopping_bean counting overlords.
my guess is H1_b visas are about to go way up.

Re:Freeman Dyson territory (1)

StefanJ (88986) | more than 2 years ago | (#39347919)

This discovery is brand new; you likely read about it a day or so ago, like I did.

Yet you're judging Dyson and his ideas on that?

An excellent piece of press-release science (5, Insightful)

Anonymous Coward | more than 2 years ago | (#39346111)

Well, the paper actually claims that there are between 2x and 100000x the number of nomad planets as there are stars. This kind of conservative claim is almost certainly right! Their ability to count on the press to distort their claims by citing only the upper bound and not the lower bound is canny and borderline unethical. Kudos to them for an excellent piece of press-release science!

Re:An excellent piece of press-release science (1)

Eponymous Hero (2090636) | more than 2 years ago | (#39346205)

they're just publishing so they don't get fired.

Re:An excellent piece of press-release science (0)

Anonymous Coward | more than 2 years ago | (#39346915)

That, and the fact that most of the nomad "planets" are snowballs smaller than Pluto. We don't even call Pluto a planet any more and while our definition of what planet means doesn't make much sense in the nomadic context, we still have an idea of what size a planet should be (with the new definition). Calling these things nomad planets (apparently using the old definition) is rather misleading.

Colonizing vs. Searching for ET Life (2)

thereitis (2355426) | more than 2 years ago | (#39346141)

Enough has been spent focusing on finding life outside out planet. Let's colonize space already! We can look for life once we get there.

Re:Colonizing vs. Searching for ET Life (0)

Anonymous Coward | more than 2 years ago | (#39346259)

Sure, we'll follow you.

Re:Colonizing vs. Searching for ET Life (1)

Tumbleweed (3706) | more than 2 years ago | (#39346609)

Enough has been spent focusing on finding life outside out planet. Let's colonize space already!
We can look for life once we get there.

Worked well enough for the crew of the Nostromo...

Re:Colonizing vs. Searching for ET Life (-1, Troll)

turkeyfish (950384) | more than 2 years ago | (#39346845)

It will be extremely hard to "look" if your eyeballs have deformed and your optic nerves have degenerated as the result of prolonged exposure to deep space. Even assuming we could chart such a course, virtually any trip in any direction would take generations, unless one were to accelerate to speeds that would probably shear living cellular material to shreds. Even if you could overcome these effects and could reach speeds 100 times faster than is currently possible, it would take 500 years just to reach the nearest star system. Think of the amount of fuel you would have to take with you just to stop once you got there, not to mention, who would want to get out for "pit stops" at a few ultracold refrigerators on the way there?

Re:Colonizing vs. Searching for ET Life (1, Insightful)

tftp (111690) | more than 2 years ago | (#39347531)

Even if you could overcome these effects and could reach speeds 100 times faster than is currently possible, it would take 500 years just to reach the nearest star system.

The humans will be forever locked on Earth unless FTL is possible. Exploration robots can be sent to faraway planets even without FTL, but they will be back many thousands of years after the launch. Humans will not be able or willing to take such a trip; they won't be humans anymore by the time they land.

This is similar to exploration of Americas. People could sail across the Atlantic ocean on Egyptian reed rafts, in theory - and perhaps a few did, but it made no impact on the rest and, if done, inflicted heavy human losses on the way there and back. Americas were not accessible until wind-driven, large ships were built that could do the trip in a reasonable time, with a reasonable chance of success, and that could carry a decent amount of commercial cargo. The same applies to the Moon right now; humans can go there and back, but such a trip is too expensive and too risky, and has very few clear reasons to even bother with.

Re:Colonizing vs. Searching for ET Life (1)

symbolset (646467) | more than 2 years ago | (#39347785)

At 1G acceleration you reach lightspeed in a little under a year.

"light-years of journey time"? (2)

Zocalo (252965) | more than 2 years ago | (#39346149)

Is that something to do with completing the Kessel Run in less than twelve parsecs?

Re:"light-years of journey time"? (2)

Surt (22457) | more than 2 years ago | (#39346921)

Thanks to C, time and distance really are interchangeable.

Kessel Run (0)

Anonymous Coward | more than 2 years ago | (#39346199)

"...brown dwarfs could become much-needed "stepping stones" for future starships to refuel on their light-years of journey time.

Finally! I can stop dragging along all those spare fuel cells when I try to make the Kessel Run in under 2 parsecs!

Re:Kessel Run (2)

turkeyfish (950384) | more than 2 years ago | (#39346853)

A parsec is a measure of distance not of time.

Re:Kessel Run (2, Informative)

Anonymous Coward | more than 2 years ago | (#39347035)

Wow, you are an idiot.

Billions and billions (1)

Howitzer86 (964585) | more than 2 years ago | (#39346211)

One can imagine that the 'dust' between us and the center of the Milky Way (as well as the arms of all other galaxies) is in fact made up of hundreds of millions of billions of planets.

Cheapest way to travel between stars (0)

Anonymous Coward | more than 2 years ago | (#39346257)

I hate to keep repeating this in every space forum or thread I visit. Starships are not going to happen. Von Neumann or self-replicating robotic space probes are the closest will ever get to "real" space travel. Humans who want to hop from star to star will have to leave behind their bodies. Instead only their consciousness is "emailed" between space "stations" built by these robotic probes.

I don't use the word "email" simply as a figure of speech. Email happens to be the most efficient way of sending written documents from one side of the planet to another. Imagine if 3D printing were a widespread and much improved reality. We'd no longer thinking of sending our gifts by DHL or Fedex. We'll just email them.

Printing out human bodies is still in the realm of science fantasy. But i'ts clearly cheaper than building an entire starship with the necessary life support and propulsion systems.

Re:Cheapest way to travel between stars (1)

DeadlyBattleRobot (130509) | more than 2 years ago | (#39346405)

I see it more as:

1. robot ships carrying seeds and frozen embryos to be developed when a suitable planet is found.

2. or life evolves to a mechanical form that can stand space radiation, long duration voyages.

Re:Cheapest way to travel between stars (1)

ChrisMaple (607946) | more than 2 years ago | (#39346525)

Good idea. I hope you're planning on using ECC. Still, it seems that there will be adventurous people who want to experience another star system, so that interstellar bodyfax is going to have to be sent back with experience intact.

Re:Cheapest way to travel between stars (1)

turkeyfish (950384) | more than 2 years ago | (#39346909)

I can see it now either way you go: physical snail mail: "Sorry no one by this name at this address". Or email: "Mailer daemon unable to transmit your message, please resend".

I think humanity would be far better off studying space with probes, telescopes, and robots and forget the manned travel as pure fantasy. Better to put that kind of money into exploring our oceans, which are actually far more poorly studied than outer space, particularly in terms of funding, with a far greater likely payoff for humanity.

There simply is no such thing as the "cheapest way to travel between the stars".

Does Someone Have a Planetary Warp Coil Available? (1)

bwohlgemuth (182897) | more than 2 years ago | (#39346337)

So it's grab a ride if it's heading your way which seems pretty bad since it's completely unsteerable and would be epically cold from no heat source. Plus the delta-V to land and take off from it.

Re:Does Someone Have a Planetary Warp Coil Availab (1)

tftp (111690) | more than 2 years ago | (#39347723)

Plus the delta-V to land and take off from it.

If you can match speed with the planet then you don't really need to land on it. You are already moving as fast as the planet, and in the same direction. The only benefit of bothering to land would be in order to mine it for energy and for shelter.

However what are your chances of finding convenient supplies of fissible or fusible elements on a random piece of rock? These are largely iron - which is the end of the line, not very usable for production of energy. If your rock-hopping trip requires several planets and you can be stuck on any of them for that reason, your chances of successful arrival drop exponentially.

You would be better off not landing at all. First, you will be living in a prebuilt ship that already has everything that you need to survive the trip (such as hibernation facilities.) Second, the ship is steerable at any time (as long as you have the energy.)

How could you use these to refuel? (4, Interesting)

ShooterNeo (555040) | more than 2 years ago | (#39346363)

Here's the best starship concept I have come up with, based upon the assumption that there are no major undiscovered principles of physics. (aka no way to cheat basic material science or travel faster than light or cheat conservation of momentum, and relativity holds)

Technology needed : with a form of nanotechnology known as "molecular manufacturing", you can produce anything of any size with control over every atomic bond. The only limits are materials and energy. You can also deconstruct any frozen object and determine it's molecular structure.

For departing Sol, use mass drivers. Either build a gigantic mass driver that can accelerate the entire starship in one go, or give the starship a mass driver that can "catch" pellets of iron fired from a smaller one you leave back at Sol.

Either way, you want to accelerate to the desired speed as rapidly as possible. This means hundreds or thousands of Gs of acceleration. The ship is mostly solid state at this point.

At 90% of the speed of the light, the ship cruises until it gets close enough to the destination star. At this point, it reconfigures the matter about the ship into a bussard ramscoop and uses this as a brake to slow down. This way, you use free floating interstellar particles as the reaction mass instead of mass carried aboard the ship. Antimatter is used as a power source, the antimatter being burned inside a power reactor inside the ship. (antimatter does not work very well as a direct source of propulsion)

The same nanotechnology used to construct the ship can also conduct perfect repairs and quickly respond to damage (given sufficient materials and energy). That way, during the many years of travel time when the ship is cruising through the space between the stars, you can repair damage from particle impacts. Also, the ship splits into dozens of pieces separated by thousands of kilometers, enough spacing so that if part of the ship collides with a large mass at 90% of the speed of light, the rest of the ship survives.

Once at the destination star and decelerated to rest relative to the star, the ship finds a small asteroid or comet near the star. It docks with it and uses the asteroid/comet as raw materials to begin expanding infrastructure. The star provides an energy source. With exponential growth, each asteroid or comet consumed increases the infrastructure (aka a swarm of various types of robots) available, allowing bigger objects to be consumed. Eventually, there would be enough equipment built to start tearing down moons for raw materials, and eventually even planets.

Once all the mass in the star system is consumed and converted into more robots, processors, etc more ships are built and sent off like seeds to more stars to continue the process.

In principle, the entire galaxy would be nothing but dyson spheres within a million years or so.

The ultimate Fermi paradox is why has this not happened yet. We are nearing the technological capability to do this. I think we will have molecular manufacturing within 100 years. Once we find a way to copy the complexity of human brains to far faster solid state circuitry, we will create super-intelligent beings who would have the ability to solve all the engineering problems within a matter of years. If the Singularity happens, then after that event this kind of expansion would be expected to start right away. Worst case scenario, within 1000 years this should start happening.

Re:How could you use these to refuel? (2)

Tumbleweed (3706) | more than 2 years ago | (#39346653)

The ultimate Fermi paradox is why has this not happened yet. We are nearing the technological capability to do this. I think we will have molecular manufacturing within 100 years. Once we find a way to copy the complexity of human brains to far faster solid state circuitry, we will create super-intelligent beings who would have the ability to solve all the engineering problems within a matter of years. If the Singularity happens, then after that event this kind of expansion would be expected to start right away. Worst case scenario, within 1000 years this should start happening.

You're assuming a hyper-intelligent being would have the same motivation to build this that you have, and no better ideas. Also, Dyson Spheres around other starts would likely block signals of their intelligence, even if those signals were detectable by our technology, or recognizable even if they were detectable. Another solution to the Fermi Paradox is found in the Outer Limits episode "Final Exam."

And none of this takes into account that we may all be a giant simulation, anyway.

Re:How could you use these to refuel? (1)

ShooterNeo (555040) | more than 2 years ago | (#39346745)

Well my assumption is that if, say, 1000 years from now, 100 separate entities have the resources to start on this kind of expansion. You know, different corporations, political entities, group minds, whatever.

Only one of them has to start it, and in another million years, the galaxy will be nothing but copies of that entity.

Basically, over the long run, if life can replicate exponentially it will do so, because the variants of life that fail or refuse to do so are quickly swept aside.

However, yes, this Fermi paradox hints that we ARE missing something huge. Maybe it really is a simulation, and we can escape or crash it. Etc.

Re:How could you use these to refuel? (-1)

Anonymous Coward | more than 2 years ago | (#39346675)

Because intelligence isn't a long term survival trait. Any starship program would require massive costs and investments with zero return possible for centuries, or millenia. Therefor, we'll never do it.

Instead we're going to stew in our own industrial wastes on this one minor planet, until something kills us. probably We kill us.

Re:How could you use these to refuel? (0)

Anonymous Coward | more than 2 years ago | (#39346741)

Cue the Reapers from Mass Effect

Re:How could you use these to refuel? (1)

turkeyfish (950384) | more than 2 years ago | (#39347011)

"We are nearing the technological capability to do this."

BS. The molecular biology is nowhere near there and is unlikely to be for decades if not centuries, especially considering that even routine sequence alignments constitute an NP complete problem for even modestly sized proteins and nucleic acids.

In contrast, what we do currently know about space biology strongly suggests that prolonged space travel is a contraindication for human life.

Re:How could you use these to refuel? (1)

Anonymous Coward | more than 2 years ago | (#39347041)

If the Singularity happens, then after that event this kind of expansion would be expected to start right away. Worst case scenario, within 1000 years this should start happening.

Nice. I'm glad that the singularity is a nice round number pulled out of the air away from happening! I'd hate to see it happen in 337 years or something. Prime numbers are such a bitch to deal with.

Your "starship concept" is a nice little piece of science fiction. And assuming infinite time, infinite energy and infinite materials, sure we could totally to it. Since we don't have infinite time, infinite energy, and infinite materials, though... it's never going to happen. The energy & material costs to send any appreciable "colonization effort" through thousands of light years of empty space only to possibly reach a planet at the other end... is simply prohibitively high. You would need to build a machine capable of traveling for thousands of years in complete isolation, healing itself through every bit of damage & repair needed to keep it moving, and never once have a single catastrophic event cause the disintegration of your ship somewhere in interstellar space because oops, it flipped an unlucky coin and hit a meteorite while traveling at .2c.

Humans have hardly existed on earth as a modern species for as long as that starship would need to survive and operate self-sufficiently to be successful. And not one single unforseen / unfixable event can happen at any point during the journey, or it's "start all over again, ha ha ha. Sorry we wasted trillions of trillions of dollars, resources, and time."

People arguing that starships are possible and almost within our reach are the space nutter versions of pointy haired bosses who have no idea how difficult what they're talking about ACTUALLY is.

Re:How could you use these to refuel? (2)

tftp (111690) | more than 2 years ago | (#39347795)

Once all the mass in the star system is consumed and converted into more robots, processors, etc more ships are built and sent off like seeds to more stars to continue the process.

It would be a sad story for inhabitants of that star system...

Re:How could you use these to refuel? (1)

FridayBob (619244) | more than 2 years ago | (#39348057)

...The ultimate Fermi paradox is why has this not happened yet. ...

We could be the first civilization in our galaxy with such grand aspirations, but with so many stars and planets around the odds are very much against that. IMO a likely explanation is that what you propose is actually much harder than you think and therefore much less likely to ever happen.

There are many serious obstacles that any such project would have to overcome before even a fleet of robots of our manufacture were ever to reach the closest nomad planet. Some obstacles are close to home, such as human nature. For instance, the grey goo [wikipedia.org] scenario comes to mind, so there's a good chance that many people would object to the development of nanobots capable of consuming whole planets. On the other hand, an interstellar effort that would not involve nanobots would probably be prohibitively expensive. I mean, why would anyone ever want to pay for something like that? Unless religion gets involved, which was great for building cathedrals, people tend to be far too concerned with their own welfare (and reproduction) to want to pay for a projects that will never benefit them. Hell, lots of people don't even like seeing their tax dollars spent on general education.

Furthermore, the distances between the stars are really, really huge. So big, in fact, you'd almost think there was a plot to prevent us from ever escaping the solar system. To put things in perspective, I once calculated that if the distance between the Earth and the Sun (1 AU) were shrunk down to 1 millimeter, the distance to Proxima Centauri would still be 267 meters. It's just not fair! When this is combined with the fact that very high speeds are necessary for long periods of time, and with this most recent discovery that space likely contains much more junk than we first thought, then it seems almost inevitable that any would-be interstellar craft will suffer too many collisions before it reaches its destination. And I'm not the first person to consider this problem. Do you remember the deflector dish on the Enterprise? Gene Roddenberry thought it would be a good idea for his starship to push space junk out of the way to prevent en-route collisions.

As for how energetic such en-route collisions would be, if the spacecraft were traveling at only 10% of the speed of light and were to hit a grain of sand, the energy released would be Ek = (1/2) x 0.00000000035 x (29,979,245 x 29,979,245)J = 157.28 MJ, which is equivalent to more than 33 kg of TNT.

Can anyone spot any holes in this logic? I hope so, because if I'm right it looks like we're stuck here.

Do microlensing surveys this? (4, Interesting)

SplashMyBandit (1543257) | more than 2 years ago | (#39346383)

Gravitational microlensing surveys have been looking for brown dwarfs and dim stars (sufficiently low luminosity they are not visible from Earth) in the galactic halo, but not enough were found to explain the mass difference (between luminous and non luminous galactic matter) to explain the observed galactic rotation curves. Planets around such low mass stars can also be seen (and have been seen, see the results by Microlensing Observations in Astrophyics [MOA] Project and associated collaborators - disclaimer I'm a former member). Depending on how small the planets are, they also could be detected (if you get very very lucky, due to the optical alignment required between observer, missing mass, and background luminous object). Given the constraints of the proportions of baryonic matter during the primordial nucleosynthesis (Big Bang/early universe) and the observed microlensing rate brown dwarfs are unlikely to account for the dark matter (AFAIK, I've been out of the game for a while). The baryonic constraints eliminated small rocks and gas clouds etc too. (I'm no expert on the nucleosynthesis calculations, however).

It would not be unusual for someone to come up with a theory that didn't take into account the known observations. For example, during the 1990's the early gravitational microlensing surveys 'rediscovered' the fact that our Galaxy is a 'barred spiral' - something the search teams were not aware of at the start of their studies (although astronomers, a different type of scientist, did know this). So it would not be unusual for someone to be missing key observations that invalidate this 'many planet theory'. Fortunately for the microlensing surveys their observations and results lead them to the correct conclusion (barred spiral galaxy), which instilled confidence in their methods and results. It doesn't take away from the fact that what was already known by astronomers was not at the time commonly known amongst the astrophysicists/particle physicists who designed the early microlensing surveys. It wouldn't surprise me if this was also the case in the paper /theory being discussed in this thread.

How to find nomad planets? (1)

gman003 (1693318) | more than 2 years ago | (#39346395)

Interesting idea (not sure it's necessarily a *good* idea, but nevertheless worth consideration), but there's one issue I can foresee:

How do you *find* the things?

Planets don't emit light. They don't really do much of anything to draw our attention. It can be difficult to spot planets even in our own solar system - Neptune, far from the smallest planet, is invisible to the naked eye, and Pluto (a dwarf planet, I know) is extremely tricky for the amateur astronomer to observe due to its distance and, more importantly, its dimness.

All our current methods for finding exoplanets depend on measuring the star it orbits - even direct imaging relies on the planets being illuminated by their star.

What I'm wondering is, how do they propose to even find these things?

Re:How to find nomad planets? (1)

marcosdumay (620877) | more than 2 years ago | (#39347031)

You put a giant telescope on space, and use gravity lensing to detect them.

Probably better done with a RF telescope.

Is there an astrophysicist in the house? (1)

artor3 (1344997) | more than 2 years ago | (#39346437)

I was taught in school, and thus assume to be the gospel truth, that planets are formed by a spinning disk of excess matter being thrown off by a young star. So where do nomad planets come from? And are they actually solid, or just mini-gas giants? After all, the galaxy is composed primarily of gas, with all the higher numbered elements being created exclusively within stars, right?

I'm having trouble seeing how these planets could form at all, let alone be so ubiquitous.

Re:Is there an astrophysicist in the house? (1)

Tumbleweed (3706) | more than 2 years ago | (#39346663)

Those spinning disks may not be dense enough to ignite into a star, but dense enough to form these plants that wind up "going rogue", is my understanding. I could be wrong. Or maybe the stars were destroyed in a war. You never know.

Sterrrriliiiiiiize! (1)

sjames (1099) | more than 2 years ago | (#39346491)

n/t

You've made a mistake! (1)

Niscenus (267969) | more than 2 years ago | (#39346949)

You are imperfect! You know what you must do.

that would be like (1)

FudRucker (866063) | more than 2 years ago | (#39346721)

finding a pink colored pebble shaped like a heart on the ocean floor

Why not... (2)

wbr1 (2538558) | more than 2 years ago | (#39346753)

...use the planets as the ships. Supposing a random distribution sunless planets, there should be plenty nearby. It would require less of a human built ship to reach. The planet itself could then be slowly pushed out of its orbit with its own huge mass drivers that use the mass of the planet itself as propulsion mass. If enough waste heat is generated in this process, it could bu used to power living areas and agricultural areas. Then speed no longer matters. You are on your new planet and simply park it in an appropriate orbit at the target star and begin terraforming it.

YOU FAIL IT (-1, Troll)

Anonymous Coward | more than 2 years ago | (#39346789)

do, or indeed what maY well remain

Been there done that (1)

Spy Handler (822350) | more than 2 years ago | (#39346815)

it's called Fleet of Worlds

after a while technical civilizations start noticing that a star is more of a liability than an asset, so they just... get rid of the star.

Cheap interstellar travel (1)

DeltaQH (717204) | more than 2 years ago | (#39346821)

Wait for nomad planet, red darf, to pass nearby. Settle on or near it Use nomad planet/red darf materials to survive (may need special technology) Wait until a new interesting place is near enough. Move to it or send some settlers and continue travel. May consider change from nomad planet/red darf on the way if materials and/or direction is more convenient. Slow but safer

Nomad Building (1)

Niscenus (267969) | more than 2 years ago | (#39346923)

With all the resources that only a civilisation like Magrathea might have, we could build our own Rama cylinder! w00t!

Step One: Find a big chunk of floating planet.
Step Two: Reconfigure the resources
Step Three: ???
Step Four: Profit
Step Five: Let your next generation prodigy meet the humans who got to whichever star or another in two weeks.
Step Six: What? You're probably dead now anyhow. Great time to be a joke.
Step Seven: This step intentionally left blank.

Puppeteers ? (0)

Anonymous Coward | more than 2 years ago | (#39346965)

Wake me up
When they find the 'Fleet of Worlds'

no stepping stone for you (1)

currently_awake (1248758) | more than 2 years ago | (#39346967)

Traveling between stars requires a lot of speed. The best (known) way is gravitational slingshot maneuvers around a large object. And stopping at the other end requires the same. So you Can't stop at some rock, you literally don't have the fuel to manage it.

mutiny by the second generation (0)

Anonymous Coward | more than 2 years ago | (#39347131)

all this talk of space travel is nice but it aint going to work. you'll get brave men & women going in these starships & the plan is to have successive generations born in space while in flight to the destination. I think as soon as the second generation becomes aware of what they're missing out on here on earth they'll mutiny against the older first generation & head back to earth.

Wise full data release is due this month (1)

moozoo (1308855) | more than 2 years ago | (#39347183)

The full sky data release from the wise missions is due this month. It can detect any unbound juptier sized planet out to 1ly. So we will soon know if there is anything like that near us.

has nobody looked for this in the pictures? (0)

Anonymous Coward | more than 2 years ago | (#39347375)

"... 100,000 planets for every star in the Milky Way ..."

And we've never happened to notice any star blinking out as something dark drifts by, relatively close to us, eclipsing it for a while?
Or has nobody looked for this in the pictures taken over the years?

It'd be sad if it turns out this has been documented as random dust spots on the film for all this time.

Stepping stones? (1)

martin-boundary (547041) | more than 2 years ago | (#39347481)

Why stepping stones? Let's just blow up a few nukes on the planet surface, and use the planet itself as a spaceship!

"What do you think, Helena?"

"Oh John, those poor aliens need our help!"

"So be it. Victor, can you reprogram Computer to land this planet on a planet?"

"Oh I don't know, John. Maybe we should go down in an Eagle instead?"

"Good thinking. Alan, lift-off in 5 minutes!"

I'll go! (0)

Anonymous Coward | more than 2 years ago | (#39347759)

I'll volunteer to look for these planets but only if my co-pilot was Wilma. No, not that That wilma.

Death by Plannet (0)

Anonymous Coward | more than 2 years ago | (#39347797)

Sooooo if there are 10s of thousands of rouge planets per sun does that mean that thousands could show up at once and the earth could be bombarded to death by rouge planets? If there are so many why have we never seen one?

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