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Do 'Ultracool' Brown Dwarfs Surround Us?
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."
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.
You see? You see? Your stupid minds! Stupid! Stupid!
... are 20% cooler than cool dwarves.
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.
Does this discovery speed up the Ross 154 - Barnards Star - Sol trade route?
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.
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.
I am a geek attorney, but not your geek attorney unless you've already retained me. This is not legal advice.
I have noticed an increasing number at my local bar lately.
I always thought that Red Dwarf was the coolest...
FTW... http://celebritymound.smugmug.com/photos/329493823_L7DcS-M.jpg
Would these ultra cool brown dwarves serve in putting more fruit to dark matter theories?
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.
I support the Slashcott and will not be reading or commenting from 2/10/14 to 2/17/14. Beta is steaming pile of dog shit
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.
Read this real quick and thought it was an advance report from Comicon...
if your lucky it will have some corn
...hip hop, don't listen to it.
We surround them.
...Me, Myself and Irene popped into my head.
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.
I call it 'The Aristocrats'
That's racist.
They're finally, going to get some diversity into Snow White?
In 3...2...1...
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 since Gary Coleman and Emmanuel Lewis were first detected in the 1980s.
http://alternatives.rzero.com/
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?
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.
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.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
Fonzie-1, Fonzie-2, Fonzie-3...
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.
What, an army of midget JJ " Walkers?
"Flyin' in just a sweet place,
Never been known to fail..."
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"?)
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.
Everyone knows that Willy Wonka ended up inviting them to work at his factory and get away from their natural predators.
Oompa-Loompa come from Loompaland, which is a region of Loompa, a small isolated island in the Atlantic Ocean. The Oompa-Loompa would end up being preyed upon or attacked by Whangdoodles, Hornswogglers and Snozzywangers, which also lived there. Oompa-Loompa are only knee-high, with astonishing haircuts, and are paid in their favourite food, cacao beans, which were extremely rare in their island. Oompa-Loompa insist on maintaining their native clothing. Only the male Oompa-Loompa are seen working in the factory
Admitedly, the Oompa Loompa are "ultracool", but I think the agreed color of their skin is typically refered to as "orange".
Refueling... Even with the best drive, you don't want to carry all your fuel with you. A quick circling stop there could boost speed and pick up more fuel, not to mention much needed gravity vacation.
I8-D
I have presented to several of my friends/coworkers/family the idea that interstellar space IS NOT the great void we seem to have been assuming for so long, but instead may well be filled with all manor of significant objects, including brown dwarfs, rogue planets, etc. We don't have to make some multi-lightyear jump across nothingness to reach the stars; we can jump from world to world to world, like a great migration wave-front, gathering resources and establishing waypoints as we go. It was an article in Analog SF magazine that got me thinking along these lines. It may take generations to reach the next major star, but at least there will be fun exploration along the way.
VASIMR to Mars!
Everything is relative. It shouldn't be too difficult to find a brown dwarf heading somewhat in the correct direction. You'd have to spend some fuel to match the trajectory, but with judicious selection you could minimize that.
Weaselmancer
rediculous.
star formation results in a range of star sizes. some sizes are below ignition threshold. we don't see them, simply because they're dark. but, statistically speaking, there should be a lot more failed stars than ignited stars. so take a random section of space, count the number of stars you can see in that, and there should be a mathematical relationship between the number of visible stars, and the number of invisible unignited smaller "stars". and this relationship should be proportional by orders of magnitude. say: for every 10 stars you see, there are 1,000 unignited balls of hydrogen sitting out there in the dark, undiscovered, and to, some extent, undiscoverable. even transit in front of distant stars would be fleeting and one time only affairs
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
No.
And further, maybe someday we'll also be able to tap zero-point energy and create matter and energy in the middle of apparently empty space.
http://en.wikipedia.org/wiki/Zero-point_energy
I can wonder if planets and asteroid orbiting brown dwarfs far away from the turmoil of the galaxy and other stars might be and ideal place for life, same as there is a lot of variety of life in the rarely disturbed deep ocean. The closer you live to a galactic core, the bigger the chance for periodic supernovas and superwaves and whatever else that may wipe out all life in some area.
We'll probably have suspended animation and "mind children" and lots of other approaches to galactic panspermia someday, too. Still, I feel we should clean up our act on Earth first, so we don't take a lot of stupid and ironic problems with us to the stars.
A 21st century issue: the irony of technologies of abundance in the hands of those still thinking in terms of scarcity.
Thanks for the speculations, and I'd encourage you to try some back on an envelope order-of-magnitude calculations to see which might make sense. For example, get a figure for the energy of an atomic bomb in some unit, and then find out the energy the sun puts out in one second in the same unit, and compare them.
Also, what may seem to make sense with today's physics might seem ludicrous with tomorrow's physics.
Maybe the sun is indeed a ball of iron.
http://www.thesunisiron.com/
Or maybe cold fusion takes place at the Earth's core at the edge of a nickel-iron core?
http://aleklett.wordpress.com/2011/05/16/the-sun-rossi%E2%80%99s-%E2%80%9Denergy-catalyzer%E2%80%9D-and-the-%E2%80%9Cneutron-barometer%E2%80%9D/#comment-5891
Or maybe we will tap zero-point energy reliably one day?
http://en.wikipedia.org/wiki/Zero-point_energy
Or the universe is mostly shaped by electrostatics?
http://www.electricuniverse.info/Electric_Sun_theory
Or the universe is a simulation:
http://www.simulation-argument.com/
And so on.
"Imagination is more important than knowledge. For knowledge is limited to all we now know and understand, while imagination embraces the entire world, and all there ever will be to know and understand. (Albert Einstein)"
Hope you keep imagining things. And think about ballpark calculations. And still hold on to your "roots" in humanity and day-to-day things like sunshine, vegetables, and laughter even when having imaginative "wings".
A 21st century issue: the irony of technologies of abundance in the hands of those still thinking in terms of scarcity.
Stars such as the sun don't go boom just because a fusion reaction is going on. And they are capable of sustaining a fusion reaction.
What you would get dropping an H-bomb on a brown dwarf is an unsustainable fusion reaction. It would go boom, not making much of a dent in something the mass of a brown dwarf. Yes, it would have an energy release larger the bomb itself would give, but not enough to ignite/sustain ignition of the star. Sorry, no supernova.
The impact pressure of random asteroids (or rather, similar space rocks) is orders of magnitude higher than that of our puny human atomic weaponry. The short version is, "If it can happen, it's probably already happened, and if not there's not a whole lot we could do about it anyway."
There is a possibility that we could find a "virgin" brown dwarf that's right on the knife's edge of fusion, but given the size of these objects there's no reason that the fusion would take it all over at once anyway.
Gary Coleman or Emmanuel Lewis?
A meteoroid with enough impact power to equal the largest nuclear bomb we have ever made impacts the earth roughly every thousand years or so. So, any brown dwarf that could be ignited by a bomb would be ignited already by stray impactors.
I suppose one could set up a scenario where a bd had, over the eons, been heating up little by little due to external forces and was now only one bomb away from ignition. But again, if it were that close to going stellar, then any ol' starquake, or maybe even tidal forces from a revolving moon, would probably set it off. And even in that instance, my totally wild-ass-guess is that it would be a localized explosion; that it would be essentially impossible to set things up such that a brown dwarf could go completely nuclear from a human level event.
There are two kinds of people: 1) those who start arrays with one and 1) those who start them with zero.
Well what would happen if you managed to drop a fusion bomb on it?
I get the impression this isn't the first time you've asked that question.
As ultracool as it gets.
Even on a successful star, no fusion occurs in the outer layers. So If I had to venture a guess, I'd say the the "surface" of a brown dwarf would be far too diffuse to support a fusion chain reaction even with an ultra powerful fusion bomb as an "spark". So to have any chance, you would need to get your big fusion bomb much closer to the core, which would be an impressive feat given the intense pressures that it would have to withstand. I'm not saying it would be impossible, but we'd be talking about pressures several orders of magnitude higher than what we have at the floor of the deepest ocean trench.
Maybe there is a very LARGE oxegen tank near UrAnus?
I hope if one is found nearby they will name it Hyundai +4904/-56.
...these objects represent some of the "dark matter" we are searching for?
I find it amusing that everyone in this thread seems to think that we're anywhere *near* the technology for a propulsion system needed to journey to another solar system in a mere 100 years. The fastest we've ever accelerated any object in history (the New Horizons probe) would take more like 80,000 years (and that's just to get to the nearest one, our galactic next-door-neighbor at just 4.2 light years away). And that's not even factoring in added time for the deceleration you would need to actually stop once you got there.
We would have to get to a significant fraction of the speed of light to even dream of getting to another solar system in 100 years. And, so far, that tech only exists in the minds of science fiction writers.
SJW: Someone who has run out of real oppression, and has to fake it.
and they're stealing my underpants...
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?
"Fusion" bombs fuse Deuterium and Tritium. Brown dwarfs already fuse Deuterium and Tritium for the part of their life cycle. That's what makes them brown dwarfs and not planets.
http://cronodon.com/SpaceTech/BrownDwarf.html
In order to create a real star, you need proton fusion. But that requires maintaining necessary heat and pressure for millions of years. If the gravity of the brown dwarf and the native deuterium and tritium couldn't do it then it is unlikely that your puny little H-bomb is going to accomplish much.
http://www.tim-thompson.com/fusion.html#ppcycle
No. The problem is not that they're cold, it's that they don't have enough mass to produce the necessary pressure. If you could somehow heat up the whole brown dwarf all you'd end up with is a puffier brown dwarf.
Fusion reactions require pressure to squeeze the reactants together hard enough to fuse. Getting them very hot can help (the atoms ram into each other harder) but only if you have some mechanism to contain them.
the new oompa-loompas. They're everywhere.
Maybe not oxygen, but definitely some kind of gas!
Thanks for the awesome post. I'll have to check out "Sunshine." I have to wonder why it hasn't been explored more in Sci-Fi. If you could force a large coronal mass on the side of the sun way from us you could catch the energy in a solar sail. On might even get a large fusion reaction by detonating an H-bomb in the corona of a brown dwarf, Your main problem would be intense gravity and currents since brown dwarf are believed to be below 250C. One might get a large mass release from a brown dwarf. This could be used to has power and heat or to boost a new solar sail. I don't think we could start a fusion implosion that would start a brown dwarf. And if we did it would probable heat up and expand outword till it cooled down. Then again it might take thousands of years for it to cool back down.
I think our best bet for for exploring beyond our solar system is to catch rides on stars as they pass close by us. Rinse and repeat if we can survive long enough we might be able to do it. I think it is our natural goal to continue to expand as that is what life does. Remember the universe isn't beautiful if no live exists to define beauty.
Or what if you were to crash two brown dwarfs together? Could that tip them from not-quite-enough-mass-to-burn into KaBoom?
Short answer is: Maybe. Deuterium could potentially collect in a chemically distinct high density layer inside a brown dwarf. If we could hit it with enough energy to start a burn wave then the whole lot, in principle, could go bang.
As for the smaller masses - Jupiter, Neptune and the Moon - probably not. Especially the Moon. Fusion fuels need to be concentrated to ignite a burn, but in all three they're mixed with materials that can't sustain a fusion burn wave. Jupiter and Neptune are probably too well mixed to chemically differentiate the deuterium, while the Moon's D/He3 is present in very low concentrations.
You can fly by and steal a bit of the dwarf energy.
And you need to know where they are as you will _not_ end up anywhere near Sirius if you do not...
if an H-Bomb is "tiny"
An H-bomb is tiny on a planetary scale, let alone a stellar one.
It's official. Most of you are morons.
There's no actual evidence of a companion star. If there were a companion star there would be perturbations of planetary orbits; and there aren't.