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Do 'Ultracool' Brown Dwarfs Surround Us?

CmdrTaco posted more than 2 years ago | from the itsatrap dept.

Space 224

astroengine writes "The recent discovery of two very cool 'T-class' brown dwarfs in our cosmic neighborhood has prompted speculation that there may be many more ultracool 'failed stars' nearby (abstract). Not only are these objects themselves very interesting to study, should there be many such brown dwarfs spanning interstellar space. Perhaps they could be used as 'stepping stones' to the stars."

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fp (-1, Offtopic)

Junior J. Junior III (192702) | more than 2 years ago | (#36799584)

I can't think of anything funny to say here. The color brown is the color of poo. I guess we are in a world of shit if it turns out to be true.

Re:fp (4, Interesting)

TWX (665546) | more than 2 years ago | (#36799606)

I guess we are in a world of shit if it turns out to be true.

Especially if they manage to show a link between this research, the fairly regular extinction events over the history of the planet, and The Nemesis Hypothetical Star [wikipedia.org] ...

Ultracool dwarves... (1)

Issarlk (1429361) | more than 2 years ago | (#36799598)

... are 20% cooler than cool dwarves.

Re:Ultracool dwarves... (0, Redundant)

TWX (665546) | more than 2 years ago | (#36799642)

but who's the coolest dwarf of all?

In high school it probably would be Dopey, as it seems that stupidity that is funny is rewarded in popularity in that pressure-cooker environment.

Outside of high school though, it's probably Doc. Doc is smart and can do cool things.

Re:Ultracool dwarves... (1)

Anonymous Coward | more than 2 years ago | (#36799712)

In high school it probably would be Dopey, as it seems that stupidity that is funny is rewarded in popularity in that pressure-cooker environment.

Outside of high school though, it's probably Doc. Doc is smart and can do cool things.

Like write scrips.

Re:Ultracool dwarves... (2)

poity (465672) | more than 2 years ago | (#36799880)

As regular brown dwarfs would have you know, "ultracool" brown dwarfs are actually hipster poseurs.

Re:Ultracool dwarves... (1)

Remus Shepherd (32833) | more than 2 years ago | (#36800066)

Yes, but they've failed the Art of the Star. Maybe they can Giggle at the Gas Giants, but they're no more than Cupcakes compared to other stars who are At the Galactic mean size.

Most importantly, what these brown dwarfs are are MACHOs (Massive Compact Halo Objects), which is a competitor to the WIMP (Weakly Interacting Massive Particle) theory of dark matter. So with this discovery we may begin a WIMPy Wrap-Up.

I'm not your stepping stone (3, Insightful)

Anonymous Coward | more than 2 years ago | (#36799618)

Yeah, sure. Because when you're on a 100 year cruise to colonize Sirius the thing you really want to do
with your intertia is slow down and stop at your local brown dwarf to pick up a pack of Coke and some cigs.

Re:I'm not your stepping stone (2)

TWX (665546) | more than 2 years ago | (#36799674)

I speculate that it wold be worth the course. Depending on the design of one's spacecraft, one could pick up particles that are in orbit of the brown dwarf to use for fuel or other raw materials, and one could use gravity as an assist to accelerate further toward one's destination.

Re:I'm not your stepping stone (1)

MadKeithV (102058) | more than 2 years ago | (#36799870)

Just imagine the bragging rights when you can say "I picked up an ultracool brown dwarf on my way to Sirius".

Re:I'm not your stepping stone (0)

Anonymous Coward | more than 2 years ago | (#36800228)

There are two of them; so: TWINs!!!

Re:I'm not your stepping stone (1)

Anonymous Coward | more than 2 years ago | (#36800022)

You can't just regurgitate space travel vocabulary and have it make sense. To claim refueling from particles with the wrong relative motion you need to have an energy-positive strategy in mind. To claim gravity assists you need the underlying math to work out.

Re:I'm not your stepping stone (0, Flamebait)

Anonymous Coward | more than 2 years ago | (#36800128)

You're dealing with a Level-III Space Nutter, probably the kind that with complete candor and earnestness will say things like "We MUST get off this ROCK"! As if the other rocks out there are different. "The SPECIES must go on!" Usually from someone who is also against socialism, but will spout species-level nonsense every time you show him a picture of a rocket. Someone who thinks "space" is all about "science", but usually doesn't even understand high-school physics.

get off my lawn or I will CRUSH YOU (0)

Thud457 (234763) | more than 2 years ago | (#36800386)

your failure at trolling makes baby Jesus cry blood.

If you're going to deride somebody's phyisic-fu in a post about rocketry, it is absolutely mandatory that you follow the New York Times style guide on being a total pompous ignoramus, to whit:

<X> seems to lack the knowledge ladled out daily in high schools.

-- NYT editorial, 21 January 1920

Note, there is a customary 49-year window to admit you didn't know what the fuck you were talking about. Although a more honest person would give it up when missiles start falling out of the air onto London.

Re:get off my lawn or I will CRUSH YOU (0)

Anonymous Coward | more than 2 years ago | (#36800858)

Right, because "Depending on the design of one's spacecraft, one could pick up particles that are in orbit of the brown dwarf to use for fuel or other raw materials" is rational, sebsible, and based on existing technology, or even foreseeable technology. And your quote is EXACTLY what I mean. A few YEARS is all it took for Goddard to demonstrate the feasability of his idea, with EARLY 20th century technology.

Today, with all the technology we (supposedly) have, we haven't gone any further or any better. So, who's the ignoramus? There IS NO NEW physics here, and THERE WILL BE *NO* such sci-fi technology, EVER. Deal with it. Insult away. Insults do not change reality, they don't move mass, they don't create miracle materials, they don't change our life span or the basic hostility of space.

Game over, Nutter.

Re:I'm not your stepping stone (1)

CrimsonAvenger (580665) | more than 2 years ago | (#36800264)

Depending on the design of one's spacecraft, one could pick up particles that are in orbit of the brown dwarf to use for fuel or other raw materials, and one could use gravity as an assist to accelerate further toward one's destination.

If you're moving slowly enough that a gravity assist off a Brown Dwarf is worth doing, you're talking about interstellar voyages taking tens of thousands of years.

And if you're taking tens of thousand of years to get to Alphacent, you're doing it wrong. Better to just wait a century or so and use better drives.

Re:I'm not your stepping stone (1)

Cable (99315) | more than 2 years ago | (#36799802)

Uh maybe stop for some gas as a 100 year trip kinda gets long. Brown dwarf stars are basically gas stations on the way to other stars, yes. A parsec is about three years in light speed but slower speeds take longer. Stop every three to five years at BD gas stations and pick up gas, food, and supplies.

Re:I'm not your stepping stone (0)

Anonymous Coward | more than 2 years ago | (#36800118)

Energetically speaking, they're more like a chocolate bar you can get by climbing 100 stories up and down. You're better off not getting it.

Re:I'm not your stepping stone (0)

Zocalo (252965) | more than 2 years ago | (#36800072)

You've obviously never been stuck around a terminal caffeine or nicotine addict who has been denied a fix. Bonus points if it's a female and they are also PMSing.

Far more likely you wouldn't actually slow down so much as skim close enough to the star to scoop up some hydrogen from the corona without actually burning up. Kind of like the old Bussard ramjet [wikipedia.org] proposal, only with a little more substance to the collection than the much slimmer pickings of interstellar space.

100 Year Travel Time... (1)

kale77in (703316) | more than 2 years ago | (#36800268)

Q. What are the odds that 50 yrs of technological progress would slash the stellar travel time, so that a 100-yr trip would likely be pointless?

Re:100 Year Travel Time... (2)

snowraver1 (1052510) | more than 2 years ago | (#36800640)

Not good. How did the last 50 years go? Oh I get it! By "Progress" you mean "Neglect" and by "Pointless" you mean "Imossible".

Slingshot? (0)

Anonymous Coward | more than 2 years ago | (#36799624)

Does this discovery speed up the Ross 154 - Barnards Star - Sol trade route?

Re:Slingshot? (4, Interesting)

Chemisor (97276) | more than 2 years ago | (#36799804)

There will never be any interstellar trade. The distances and velocities involved require energy expenditures vastly higher than the cost of any valuables you may wish to transport. You might say the costs will be "astronomical". The only movement between stars will be radio signals and initial colony ships.

Re:Slingshot? (0)

Anonymous Coward | more than 2 years ago | (#36800182)

Whoooosh. That's the sound of a fully laden Panther Clipper (with the Joke on board), going way, way over your head.

Re:Slingshot? (1)

Baloroth (2370816) | more than 2 years ago | (#36800194)

There will never be any interstellar trade.

By Chemisor. Quoted so as to be preserved for all antiquity. "Never" is a very long time. Yes, with current technology, there won't be. Thing is, technology never stays current. You're probably still right, but we'll see. Or, our great-great grandchildren will, at least.

To our knowledge it is truly never (0)

Anonymous Coward | more than 2 years ago | (#36800658)

To our current knowledge the gp is right : it is truly never. From the antiuities to now, we have refined our knowledge of physic, but we never removed limitation. We keep adding them on. For example newtonian mechanic allowed speed greater than light. Now to our knowledge it is an absolute limit. The more I learn in physic, the more limitation come in, and the exception to the rules come in extrem cases : extremly high pressure, boson condensate, low vaccuum and vbery short distance, but even those exception respect the primordial speed limitation. So barring an incredible discovery (a possibility which cannot be discarded but has about as much probability as a second coming), the GP is right. never is long, but sadly for this universe, an extremly likely bet.

Re:Slingshot? (3, Insightful)

rubycodez (864176) | more than 2 years ago | (#36800196)

Information may be what is traded. But self-replicating mining and factory machines can bring ship building and fuel mining costs to essentially zero. Then the only cost is time of assembly and time of transit. Maybe there is something physical that would be worth it.

Racist (5, Funny)

Sedated2000 (1716470) | more than 2 years ago | (#36799634)

I can't believe how racist slashdot has become. They may be ultra cool, but calling them brown is inciting hate. African American little people is the PC term.

Re:Racist (2, Insightful)

Rhaban (987410) | more than 2 years ago | (#36799682)

I can't believe how racist slashdot has become. They may be ultra cool, but calling them brown is inciting hate. African American little people is the PC term.

African American little people with sunglasses.
You can't be ultracool without sunglasses.

Re:Racist (0)

Anonymous Coward | more than 2 years ago | (#36799722)

African American little people don't exist. Hispanic Little People and Native American little people is what you were looking for, and African American holes.

Re:Racist (0)

Anonymous Coward | more than 2 years ago | (#36799778)

You obviously haven't seen Bad Santa. [imdb.com]

Re:Racist (0)

Anonymous Coward | more than 2 years ago | (#36799894)

WHOOOSH! You didn't get the meta joke.

Re:Racist (0)

Anonymous Coward | more than 2 years ago | (#36799784)

I for one don't see the point of calling them "American", of all things. The U.S. of A. owns the space now, does it? I'd say a more correct, more non-discriminatory term is needed. Fjkghdbjhh, for example, has no negative connotations attached to it.

Re:Racist (4, Funny)

PvtVoid (1252388) | more than 2 years ago | (#36799848)

I can't believe how racist slashdot has become. They may be ultra cool, but calling them brown is inciting hate. African American little people is the PC term.

Mass disadvantaged stars of color.

Re:Racist (0)

Anonymous Coward | more than 2 years ago | (#36800292)

Typical. Americans now think the galaxy is America...

Re:Racist (0)

Anonymous Coward | more than 2 years ago | (#36800784)

I thought Hispanics identified themselves as brown, while African Americans identify themselves as black.

Hipster trends... (0)

mpoulton (689851) | more than 2 years ago | (#36799654)

I suppose a brown dwarf might be considered cool in an ironic sense, sort of a reclaiming of both the super-lame color brown and also a traditionally uncool congenital condition. It's the ultimate hipster combination. Especially since all brown dwarfs currently alive to benefit from their new-found ultacoolness were both brown and dwarfy BEFORE IT WAS ULTRACOOL.

Yes!! (0)

Anonymous Coward | more than 2 years ago | (#36799666)

I have noticed an increasing number at my local bar lately.

Cooler Dwarf? (1)

grimmjeeper (2301232) | more than 2 years ago | (#36799670)

I always thought that Red Dwarf was the coolest...

Re:Cooler Dwarf? (1)

UnresolvedExternal (665288) | more than 2 years ago | (#36799792)

Nope, a brown dwarf is a really froody dude who always knows where his towel is.

The ULTRAcoolest... (1)

Anonymous Coward | more than 2 years ago | (#36799678)

FTW... http://celebritymound.smugmug.com/photos/329493823_L7DcS-M.jpg

Re:The ULTRAcoolest... (0)

Anonymous Coward | more than 2 years ago | (#36800684)

Too bad you're so HTML challenged, that was pretty funny/ontopic.

Embed URLs with:
<a href="URL"/>descriptive text</a>

like:
<a href="http://celebritymound.smugmug.com/photos/329493823_L7DcS-M.jpg"/>Ultracool brown dwarf</a>

Does it matter to dark matter? (1)

pinkj (521155) | more than 2 years ago | (#36799700)

Would these ultra cool brown dwarves serve in putting more fruit to dark matter theories?

Re:Does it matter to dark matter? (1)

PvtVoid (1252388) | more than 2 years ago | (#36800042)

Would these ultra cool brown dwarves serve in putting more fruit to dark matter theories?

Almost certainly not. Dark matter made up of brown dwarfs was searched for in the gravitational microlensing experiments like the MACHO project [anu.edu.au] . They didn't find nearly enough to account for the dark matter.

Re:Does it matter to dark matter? (1)

delt0r (999393) | more than 2 years ago | (#36800180)

And the bullet cluster observations cannot be explained with MACHOs either.

Re:Does it matter to dark matter? (2)

dido (9125) | more than 2 years ago | (#36800148)

No. As much as it seems fashionable to bash (non-baryonic) dark matter here on Slashdot, our current astrophysical theories put constraints on how much baryonic dark matter (MACHOs) is possible. Our current theories on Big Bang nucleosynthesis place bounds [arxiv.org] on how much baryonic matter can remain dark. If there really were enough baryonic matter to account for all the dark matter that should be there based on indirect observations, then the abundances of various isotopes produced by Big Bang nucleosynthesis would be quite different from what we observe. That could also mean that our current theory of the Big Bang is completely wrong, but that seems unlikely to say the least. These theoretical considerations imply that even if more MACHOs are found, non-baryonic WIMPs will still have to make up a large fraction of dark matter.

Re:Does it matter to dark matter? (1)

HiThere (15173) | more than 2 years ago | (#36800176)

No. Brown dwarf stars are made of baryonic matter, just like you and I. Dark matter must be non-baryonic, or physics needs to be totally redone. (A difficult job, as coming up with even one chunk of math that matched what we know of quantum behavior took lots of work.)

Basically, current physics predicts the number of protons+neutrons created at the time of the "big bang", and thus the number of baryons in the universe. There aren't enough of them to account for the "dark matter". And all current alternative theories seem to agree on the number of baryons (at least approximately). E.g., the crash of branes is one alternative to the big bang. Some of them could probably be adapted to allow differing numbers of baryons (I suppose that if the universe is cyclic, perhaps not quite everything collapsed at the last big crunch), but the ration of hydrogen to helium needs SOME explanation. And the one that currently seems to fit predicts a particular number of protons+neutrons in the universe. So dark matter isn't composed of protons or neutrons.

The only thing that surprises me is surprise (-1)

ElectricTurtle (1171201) | more than 2 years ago | (#36799728)

I know I'm a layperson, but I think astrophysics really needs to move beyond the assumption that if we can't see it it isn't there. The more closely we're able to study space the more we find that it's full of stuff of every size at every conceivable distance. I honestly thing it's safe at this point to assume that nearly every star has planets as a simple matter of the nature of stellar accretion processes, and further that for every star that's bright enough to see there are probably a dozen too dim. This is why we can't figure out dark matter/energy.

Re:The only thing that surprises me is surprise (3, Informative)

ledow (319597) | more than 2 years ago | (#36799774)

Tut! Oh God! Why didn't we think of this! It's so obvious! That's where all our research money has gone to waste, assuming that we are omnipotent in our calculations and not including error ranges!

Hell, let's just assume that that 83% (or thereabouts) of all matter in the universe being "missing" is just us overlooking that there might be planets on every star (and the fact that the biggest planet in our own Solar System weighs less than 0.1% that of the Sun).

God, it's so obvious. Why did we never take this into account in any of our billion-dollar-funded research programs filled with (quite literally) rocket-scientists?

Or maybe we did, you pillock...

Re:The only thing that surprises me is surprise (3, Insightful)

ledow (319597) | more than 2 years ago | (#36799846)

P.S. we infer most of the mass of the universe through the movement of things we can observe (because all mass bends space-time) - and we get a pretty god-damn accurate picture of what MUST be in it's local neighbourhood for it to act like it does. The fact we can't see the mass itself is neither here nor there - we're literally looking at how a galaxy (BILLIONS OF STARS!) behaves and inferring how much it and it's surroundings must weigh in order to act like that. There's about 170 billion galaxies to look at.

On those scales, extra planets and a few missing stars don't even factor into the error ranges because they are so inconsequential. Hell a couple of extra galaxies doesn't even register.

Re:The only thing that surprises me is surprise (1)

ElectricTurtle (1171201) | more than 2 years ago | (#36800044)

This is the problem, you think that just because stars are so massive that it makes all the other smaller masses irrelevant. Yeah, 0.1% doesn't seem like much in one instance, but if there are a thousand you can't see then you have, albeit distributed, a solar mass that you can't see. And then multiply that how many times? Billions? Trillions?

The fact that we can't even prove or disprove that a brown dwarf orbits our own star demonstrates that our 'accuracy' about our local neighborhood can't be all that good. If we can't see something that massive when it is relatively right in front of our face, there could be an innumerable amount of them floating outside of any obvious gravitational influence on other bodies.

Smaller masses in the universe almost certainly outnumber the larger masses exponentially. Just look at the contrast between giants and dwarfs in the stellar catalogs. Would you discount dwarfs because they are so relatively less massive than supergiants? Of course not, there are too few supergiants and too many dwarfs to do that. So why do you discount all the unseen sub-stellar material? When you see these patterns of scale, failure to extrapolate is irrational.

Re:The only thing that surprises me is surprise (3, Interesting)

delt0r (999393) | more than 2 years ago | (#36800280)

The number of extra planets or dark stars you would need to matter, *would* show up because there would need to be soo many. They have been looked for you know. For example if there are millions more of these cold brown dwarfs than what we already have estimated, then the average distance to them would be so small that we would be able to observe many of them (probably would imply at least a few within the ort cloud). We would see many more micro-lensing events ... etc etc.

You can't have your cake and eat it too. If there is enough to explain dark matter, there is more than enough that observing them would be quite trivial.

On top of all that, such objects do not explain other observations of dark matter. In particular, the bullet cluster. We can in fact "see" dark matter.

Re:The only thing that surprises me is surprise (1)

Shadowmist (57488) | more than 2 years ago | (#36799790)

I know I'm a layperson, but I think astrophysics really needs to move beyond the assumption that if we can't see it it isn't there. The more closely we're able to study space the more we find that it's full of stuff of every size at every conceivable distance. I honestly thing it's safe at this point to assume that nearly every star has planets as a simple matter of the nature of stellar accretion processes, and further that for every star that's bright enough to see there are probably a dozen too dim. This is why we can't figure out dark matter/energy.

If the arrangement of discovered exoplanets has taught us anything, it's that most of our safe classic assumptions need to be wadded up and thrown in the nearest dustbin. And yes you are a layperson who probably knows nothing about the practice of astronomy or astrophysics, or high energy physics. It's not a matter of "seeing" or 'not seeing". If something exists it makes it's imprint, it's footprint in the universe around it, in the gasses it's thrown off, it's interaction with other things or just the presence of it's gravity. Astronomy does not make simplistic assumptions like the one you put out. Right now it's about building the best possible model to fit the observations we make now and predict what we'll make in the future.

Re:The only thing that surprises me is surprise (1)

Baloroth (2370816) | more than 2 years ago | (#36799862)

The problem is, if we can't see it, how do we know if its there or not? You can speculate, of course, and a surprisingly large amount of astrophysicists do precisely that. That's pretty much what "dark matter" is: pure speculation about something we can't see and haven't yet directly observed, but which happens to fulfill a certain role in our theory of the universe. This has the obvious problem of being rather unscientific: until we devise some method of testing for its existence, we can't, empirically, say it exists. Its not completely unscientific: it might be possible to prove it doesn't exist, in the form we currently envision it. In which case scientists basically just tweak the numbers till it can exist. Not a criticism: that's kind of how science works.

However, without some positive evidence, we can't simply assume something we can't see exists. You mention assuming every planet has stars. Of course, many of the ones we've observed do, but there are very many kinds of stars, and its a safe bet that entire classes probably don't have planets. Stars that formed early in the universe, for instance, might not have been able to form planets because of forces from other stars. Or stellar winds that some stars produce might have blown away all the material needed for planets. The possibilities are endless, and if we simply assume things without proof about the way the universe works, we can basically kiss all the knowledge we have of the universe goodbye. The key to any assumption is to first prove or disprove it, then move to the next assumption.

Re:The only thing that surprises me is surprise (2)

delt0r (999393) | more than 2 years ago | (#36800346)

Evidence: The bullet cluster. The observations imply that there is a huge amount of mass that was moving with each galaxy before the collision, that is not baryonic. That is interacts only via the force of gravity and is not affected (or at least very very weakly interacting) via the other forces, most importantly the electromagnetic force.

There is quite a few other effects that dark matter can explain nicely. We are in fact devising experiments to attempt to observe dark matter particle candidates.

Re:The only thing that surprises me is surprise (1)

Zocalo (252965) | more than 2 years ago | (#36800112)

Yeah, the next thing you know something like this [theonion.com] is going to happen. It's just a matter of time, I tell you!

Re:The only thing that surprises me is surprise (0)

Anonymous Coward | more than 2 years ago | (#36800668)

Astrophysics moved beyond this over a century ago [wikipedia.org] . If you knew anything about astrophysics or astronomy you would have known this. Granted, this kind of thinking predates even this event but this is probably the best known tale in astronomy of someone knowing something existed without direct observance.
 
And I must also point out that it's great that you show some level of interest in this kind of thing. While I don't think you should need to have a PhD in astrophysics to discuss it you should still get some base knowledge of what you're talking about before making grand statements of this nature or making assumptions that are plainly false. You really should take the time to sit down and study up a bit before coming off like a jackass. I recommend AstronomyCast [astronomycast.com] for starters.
 
And I'm really not trying to be a smartass but the resources to have a basic understanding of these types of things is so easy to get to and most of them are free. It's a shame to go around looking like a fool for it.

Yes there are (3, Informative)

Cable (99315) | more than 2 years ago | (#36799756)

In order to have elements beyond carbon one needs a bigger star than our yellow sun. Large stars tend to supernova and become brown dwarfs or black holes in some cases. Some stars fail and become brown dwarfs as well. But you can still get hydrogen from them from solar winds for spacecraft.

It is hard to detect them because the brown dwarfs are Earth size and do not give off much heat or light. Our sun Sol is supposed to have a companion star nearby called Nemesis that is a brown dwarf and throws asteroids at our solar system.

Re:Yes there are (4, Informative)

scharkalvin (72228) | more than 2 years ago | (#36799926)

Large stars will never become brown dwarfs. They will end up as one of the following:
White dwarf, neutron star, or black hole. A white dwarf will eventually cool and become a black dwarf. The chemical composition of a white dwarf is NOTHING like that of a brown dwarf. A brown dwarf is hydrogen and a few other elements. A white dwarf has very little hydrogen, it is the 'ash' of a star that once was and is made of mostly heavier elements that are the result of fusion.

Re:Yes there are (0)

Anonymous Coward | more than 2 years ago | (#36800634)

Does Jupiter qualify to be called a brown dwarf? Serious question, no Ur-brown-anus jokes, please.

Re:Yes there are (1)

Baloroth (2370816) | more than 2 years ago | (#36799956)

Seriously? Its called "Nemesis", its a brown dwarf, and it throws asteroids at us. Why does this sound like the plot from a video game?

Oh, and here [wikipedia.org] is the link. Thought for a second you completely made it up, but apparently it was someone else who completely made it up. (That might be a little harsh, but it is purely hypothetical)

Re:Yes there are (1)

HiThere (15173) | more than 2 years ago | (#36800276)

I think it's been decided that Nemesis "probably doesn't exist". At least in the form originally hypothesized. But there are tentative signs that *something* exists that does approximately what it was proposed that Nemesis would do. Tentative is far from proof, however, and "something" could cover everything from a black hole to a large planet in an eccentric orbit. Depending on how much of the evidence you wish to attribute to chance. (Some of it clearly is, but how much? And we can't tell. Besides, given the proposed mode of action, lots of times one would expect the asteroids to just go into very eccentric orbits...perhaps hitting us later, but usually either having orbital decay and regularization, or being captured by Jupiter or Saturn.)

Re:Yes there are (1)

Anonymous Coward | more than 2 years ago | (#36800048)

[Posting anon, mod points.]

Large stars tend to supernova and become brown dwarfs or black holes in some cases.

Brown dwarfs are specifically failed stars, somewhere between Jupiter and a red dwarf. When large stars supernova, they never become brown dwarfs.

I got a brown dwarf for ya (1)

Anonymous Coward | more than 2 years ago | (#36799770)

if your lucky it will have some corn

If you don't like... (1)

Anonymous Coward | more than 2 years ago | (#36799810)

...hip hop, don't listen to it.

It may feel like they surround us, but no. (0)

Anonymous Coward | more than 2 years ago | (#36799856)

We surround them.

When I read the headline... (0)

Anonymous Coward | more than 2 years ago | (#36799912)

...Me, Myself and Irene popped into my head.

All foam, no beer (4, Interesting)

MonsterTrimble (1205334) | more than 2 years ago | (#36799918)

The idea of Y-class brown dwarf stars are neat and all, but this whole 'stepping stone' idea is not really explained. Why would we use these as stepping stones? Is there an advantage to it? I don't understand why we would use them is all.

Re:All foam, no beer (3, Interesting)

calderra (1034658) | more than 2 years ago | (#36799986)

Random ideas off the top of my head: Rogue stars of any sort might carry clouds of hydrogen and/or other elements, possibly even rocky asteroids and protoplanets, with them. It might be possible to refuel in one of these systems. Gravitational slingshots become an interesting idea, possibly allowing for some really interesting maneuvers. A gravity source also makes orbiting possible, so we could send ahead robotic probes to orbit some big external fuel tanks to await a manned mission that will carry less mass on-board and pick up supplies along the way- the probes can use gravitational assist to cut down on fuel use when stopping and rejoining the manned mission. There's just all sorts of potential, although again I'm mostly talking about any rogue star and not just brown dwarves.

Re:All foam, no beer (1)

MonsterTrimble (1205334) | more than 2 years ago | (#36800198)

I understand that, however I wonder if a 'refueling' is possible within the constraints of near-future (100 or so years) technology.

What I could see happening is setting up waypoints or space stations near the stars which are used much like the forts were during colonization of North America.

Re:All foam, no beer (1)

jmrives (1019046) | more than 2 years ago | (#36800624)

Well, the term "stepping stone" may be a bit misleading. If I had to guess, I would say one possible use of a large gravity well is as an accelerating slingshot.

Re:All foam, no beer (1)

prograde (1425683) | more than 2 years ago | (#36800636)

Why would we use these as stepping stones? Is there an advantage to it? I don't understand why we would use them is all.

Because they are closer. from the article:

our nearest known neighbor will soon be a brown dwarf rather than Proxima Centauri.

So, we could stop off at one of these on the way to Proxima Centauri.

That's racist. (0)

Anonymous Coward | more than 2 years ago | (#36799980)

That's racist.

Politically Incorrect? (0)

Anonymous Coward | more than 2 years ago | (#36800068)

They're finally, going to get some diversity into Snow White?

JWST, Mass (2)

LordMyren (15499) | more than 2 years ago | (#36800116)

Yet another place the JWST (James Webb Space Telescope) would be fantastically useful!

Also, how seriously would the presence of previously undetectable ultra-cool stars affect the search for dark matter? Aren't we looking for energy/matter based off some energy level, and might that mass be tucked away in the form of ultra-cool stars, just to cool to detect?

I've suspected this... (1)

tverbeek (457094) | more than 2 years ago | (#36800190)

I've suspected this since Gary Coleman and Emmanuel Lewis were first detected in the 1980s.

Not useful as refueling dumps? (2)

wisebabo (638845) | more than 2 years ago | (#36800366)

So (like another poster) I'm not sure how useful these would be as refueling dumps (stepping stones). I mean, once you've gotten a starship up to speed then slowing it down to refuel just to speed up again just doesn't make sense. I guess the only use would be if there were consumables that could be obtained for "generation ships" or if some large piece of the ship needed repair material (as in the ice shield on the starship in Arthur C. Clarke's "The Songs of Distant Earth"). I guess they might make sense if they were power stations that could beam (lasers?) energy to a passing ship.

Another (briefly discussed) issue is that of missing matter. I realize that the amount of planetary matter must be a negligible contribution but why couldn't there be 100s or 1000s of brown dwarfs for every sunlike star? Is it because we'd see a lot more microlensing events or our Oort cloud would be perturbed much more frequently? It would be kinda cool if there were much more of these things out there rather than stuff we can't interact with.

Are there any "habitable zones" around them? Sure there wouldn't be any light but it'd be like being next to a nice campfire for some really close orbits. Would the orbits be too close and decay in a geologically insignificant amount of time?

If we ever got fusion drives (but nothing better) maybe having lots of these things would allow galactic expansion as a long slow crawl at very small fractions of the speed of light. In which case setting up colonies of couple thousand AUs over many millennia could gradually establish a dark web between the brightly lit stars (so much for Star Trek). These bodies then wouldn't be waypoints. They would be our homes.

Could we blow them up? (Pure speculation). (4, Interesting)

wisebabo (638845) | more than 2 years ago | (#36800824)

So these brown dwarfs are essentially big balls of (mostly) hydrogen with the centers under tremendous pressures and temperatures but not quite hot enough to "light" (in a fusion sense). Well what would happen if you managed to drop a fusion bomb on it? (On or near the surface where the temperatures are low but the high gravity might still compress the hydrogen into the megabar range).

While (probably) it would just fizzle, could the concentrated energy ignite just enough so the whole star went boom? (Like a Type I supernova?). I mean the "temperature" of an H-Bomb is in the hundreds of millions of degrees maybe it just requires one tiny (if an H-Bomb is "tiny") spark. Just like you can pour millions of gallons of gasoline on a barely sub-critical mass of Uranium and it won't go bang but one small neutron generator and you've got a mushroom cloud. While the impacts of asteroid and larger bodies could deliver a lot more energy, an H-Bomb could do so more INTENSELY.

I guess this is what the first H-Bomb scientists were worried about when they feared the first H-Bomb *might* ignite the water vapor in the atmosphere and consume the entire world. Just how easy would it be to blow one of these things up? Could you do it with even smaller cooler less dense bodies, say Jupiter (as proposed by sci-fi writer Charles Sheffield) or Neptune? (Tried it on earth, nope doesn't work). Lastly, our sun is already alite, but the RATE of fusion reaction is very slow (each gram of the sun produces far less energy per time than, say, a live elephant). Could we speed it up? Could an H-Bomb (or a suitably powerful laser such as was used in one of the Man-Kzinti war sci-fi books) trigger a local (or maybe not so local) explosion?

I guess this was the general idea behind the movie "Sunshine" (good movie). Seems they had some sort of very dense (causing a local gravitational field) fission bomb to re-ignite the sun. Wish they had a companion book to flesh out some of the details.

Anyway I know these ideas are probably non-sensical to any physicist but don't have enough math and physics knowledge to calculate it for myself. If anyone of you is so inclined and it won't take much time or effort, I'd appreciate the debunking (or not!) of this idle speculation.

(For even crazier speculation, how about igniting all that supposedly great fusion fuel Helium-3 that is just lying around on the lunar surface? Would it be enough to blow the moon out of orbit a la "Space 1999"?)

Let's name em (0)

Anonymous Coward | more than 2 years ago | (#36800478)

Fonzie-1, Fonzie-2, Fonzie-3...

Might be useful as gravitational slingshots. (0)

Anonymous Coward | more than 2 years ago | (#36800936)

I am reminded of the voyager series space probes, that used Jupiter's massive gravity well as a slingshot to reach saturn, and from there, Uranus and Neptune. (Also known as the "Grand Tour".) The mission was possible because of a rare orbital configuration that only happens once every few hundred years.

In this case, we would launch a probe pretty much directly at our sun, use the sun's gravity to accelerate the craft much faster than chemical rockets would normally be able to handle, then swing around the sun towards one of these brown dwarf stars. The probe would slow down as it left our solar system due to interaction with the heliopause and heliosheath of our own solar system, and later that of the brown dwarf it would interact with.

If we presume that these "nearby" objects are closer than our more luminous neighbors (There are 3 systems that are within 7 light years distance...), it might only take a few decades to reach one, instead of a few centuries to reach one.

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