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Rogue Brown Dwarf Lurks In Our Cosmic Neighborhood

Posted by Soulskill on from the brown-dwarf-rogue-lurks-in-ironforge dept.

astroengine writes "The UK Infrared Telescope in Hawaii has discovered a lone, cool brown dwarf called UGPSJ0722-05. As far as sub-stellar objects go, this is a strange one. For starters, it's the coolest brown dwarf ever discovered (and astronomers using the UKIRT should know; they are making a habit of finding cool brown dwarfs). Secondly, it's close. In fact, it's the closest brown dwarf to Earth, at a distance of only 10 light years. And thirdly, it has an odd spectroscopic signature, leading astronomers to think that this might be the discovery of a whole new class of brown dwarf."

31 of 188 comments (clear)

  1. thats actually really close... by Coraon · · Score: 2, Interesting

    I believe at currently achievable theoretical speeds we might be able to make it there with like a robotic probe in 100 years or less!

    --
    -Ours is the wisdom of Solomon, the magic of Merlyn, the fall of Icaris.
    1. Re:thats actually really close... by tmosley · · Score: 3, Insightful

      You think we can send a probe an average of 1/10th C, including acceleration and slowdown?

    2. Re:thats actually really close... by Waffle+Iron · · Score: 2, Insightful

      To paraphrase Yogi Berra: In theory, currently achievable theoretical speeds are achievable. In reality, they aren't.

    3. Re:thats actually really close... by WCMI92 · · Score: 3, Interesting

      You think we can send a probe an average of 1/10th C, including acceleration and slowdown?

      Theoretically possible using a nuclear power source and ion propulsion. Probably would be decades before we could practically do it, but the idea isn't outside the realm of possibility starting with existing technology...

      It'd be a lot easier though to try this with Alpha Centauri though. It's only 4 light years away, not 10.

      This is an interesting find though. Given the lack of planets or sign of the remnants of the formation of a star/planetary system I'd say this thing is definitely a rogue, that formed in another planetary system that was ejected by gravity. Brown dwarfs actually are able to do deuterium (lower mass ones) and even lithium fusion (higher mass ones) for a short period of time (100MY or so for the fuel to run out) but this one may be too small to have done either.

      We certainly are going to discover a lot more of these as we get better and better instruments. They are likely very common, and we are likely to see the discovery of tons more brown dwarfs and very low mass red dwarfs in the coming decades. What is fascinating would be to know exactly where the line is between a very low mass red dwarf that can initiate and sustain core hydrogen fusion and a brown dwarf that either never starts core hydrogen fusion or cannot sustain it.

      --
      Corporatism != Free Market
    4. Re:thats actually really close... by linzeal · · Score: 3, Informative

      Project Orion is the only one I have ever heard of that claims such speeds.

      --
      An Education is the Font of All Liberty
    5. Re:thats actually really close... by K.+S.+Kyosuke · · Score: 2, Insightful

      An ion engine? Hardly. BTW, the cheapest way for a long, long time will probably be a reaaally large space-based telescope somewhere far away to keep it nice and cold. Not cheap in absolute terms, but certainly cheaper than any kind of interstellar probe.

      --
      Ezekiel 23:20
    6. Re:thats actually really close... by ushering05401 · · Score: 5, Funny

      Slowdown? We won't get military support that way, therefore no funding. We smash something into it at maximum speed and let the military gather transport and devastation metrics from a collision involving speeds never before recorded by human instruments.

      Then the astronomers study the ejecta, the engineers review vehicle performance metrics, the doomsday prophets rework their asteroid impact models, the cosmologists continue to try to convince their mother-in-laws that they really are cosmologists despite not knowing anything about t-zones, foundation blending, manicuring, waxing.... and no, that doesn't mean they went to a bad 'school of cosmology.'

    7. Re:thats actually really close... by Rakishi · · Score: 2, Insightful

      There is a big difference between the basic technology existing and a practical device using that technology existing. The Apollo project didn't cost $80 billion because the technology was revolutionary. It cost $80 billion because getting something that big to work properly is in itself a massive pain in the ass even if you have all the technology. Hell, just recreating the Apollo project would probably cost close to $80billion without blueprints and we already did it once before. Essentially it's an engineering problem rather than a scientific one.

    8. Re:thats actually really close... by sznupi · · Score: 2, Insightful

      If we would really want to we can get rid of the slow down by simply performing a flyby. Who knows how acceptable the former would be of course, considering the limited science and that such mission wouldn't get funding very often...

      --
      One that hath name thou can not otter
    9. Re:thats actually really close... by GigaplexNZ · · Score: 3, Insightful

      Wouldn't solar sails fail to work once you reach the Heliopause?

    10. Re:thats actually really close... by RockDoctor · · Score: 2, Informative

      Even though it uses light and not solar winds, an equivalent concept of a Heliopause would probably still take effect (the closer you get to the other star the more its light counters Sol).

      True, but not particularly important. Most of the benefit of the "launching lasers" you get by getting up to a high speed fairly soon, reducing your time of flight. If you're only (or largely) powered by launching lasers and solar sails, then you'll be expecting to have an asymmetric journey in both distance and time, because the high intensity of the "launching lasers" at the Sol end of the journey would need to be counteracted by the lower intensity of the light from the target star over a longer distance and duration.

      Using an interstellar laser to push it isn't really practical as at those distances it becomes horribly difficult to aim the laser with such precision. Assuming your laser could aim precisely, by the time you realise you are pointing in the wrong direction and make a correction, it will take years for the correction to take effect, by which time the sail has already moved.

      Your laser will have a certain divergence of beam, due to manufacture errors. As you get further away, the intensity will drop (this is part of the reason that you get up to speed as soon as possible, and will, indeed eventually the "launching lasers" will become useless. But regardless, you don't steer the ship by moving the laser, you steer it by tilting the sail.
      With a solar sail, you get two types of drive. Some drive is from particles of solar wind travelling (more-or-less) radially out from Sol hitting the sail and sticking. These transfer their momentum vector directly to the sail, and hence to the towed payload. Their impulse on the sail will always be radial to the target star (to moderate precision). The other source of drive though is from photons that hit the sail and are reflected from the sail's surface. These, as a moment's consideration will tell you, will provide an impulse vector to the sail (and hence, to the payload) which is in the direction of the bisector of the angle between the direction of the incoming photon and the direction of the outgoing photon. In short, the sailor can "tack" his vessel against the light-wind from the "launching lasers". The control system is at the sailor's end, not the launching laser's end ; the launching laser jockey simply points his laser at the target star and leaves it up to the sailor to stay within the beam ; the sailor has to work out how to make the final cruise form the light beam to the target star, knowing that an error either kills everyone on board, or means an unnecessary year in the tin can (which is also likely to be a death sentence for the erring sailor).

      Byproduct : if a solar sail powered probe is launched from star A to star B, then for a number of years before the arrival of the probe at star B, there will be an intense, monochromatic source of light shining from star A at star B. In short, a very bright warning light.
      Reference reading : " The Mote in God's Eye (Orbit Books) (Paperback) by Larry Niven and Jerry Pournelle (Author) ; classic hard SF.
      Byproduct 2 : if your solar sail-powered craft approaches the target star without being greeted or communicated with ... then the inhabitants are either dead, or live underground, or have yet to learn to bang the rocks together. Or just possibly use visual pigments that work in a very different part of the spectrum to your launching lasers.

      Hmmm : multi-wavelength launching lasers. Possible? Helpful? Problematic? I'll have to think about that.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
    11. Re:thats actually really close... by RockDoctor · · Score: 2, Interesting

      BTW, the cheapest way for a long, long time will probably be a reaaally large space-based telescope somewhere far away to keep it nice and cold. Not cheap in absolute terms, but certainly cheaper than any kind of interstellar probe.

      For certain meanings of "long time" : I'm a geologist, and my meaning of "long time" is rather different to the meaning of a Thai bar girl telling me that she'll "love me long time". Though our meanings of "love" are probably more-or-less congruent. I see your "long time" and wonder if the duration would really be noticeable.
      The process of putting the bigger and bigger telescopes progressively further and further away will of course give us experience in several incrementally important technologies : those of making and moving big things in space, and those of keeping people in a habitable environment in space for longer and longer periods of time. By the time that we're putting the third Outer Kuiper Telescope in place, each one of which involves sending a ten-person crew on a three year mission to the outer edge of the Kuiper Belt, then the prospect of sending ten consecutive thirty-person trips on thirty year missions to Proxima Centauri would appear considerably less daunting.
      The interstellar trip would appear even less daunting if they knew that two ten-person inhabitation modules (a standard design, with a hundred-year proven working life) had arrived and gone into a parking orbit at Proxima, and that another four modules are in flight, due to arrive before they do with additional ones being launched every second year thereafter until Proxima Colony tells Old Home Terra to stop throwing tin cans. The automated solar cell (hmmm, that name will have to change!) factory might also be in flight, so the first things to do on arrival at Proxima would be to collect several gigatonnes of iceballs for reaction mass (just like refuelling the reactors for the Outer Kuiper Telescope), and then settle down to breeding and building another asteroid civilisation. Planets? Well, if there are any, they might get colonised one day, but the important things would need to be done first. After all, terraforming is really hard, and it's hard to envisage how the original Earthlings did it without modern technology.

      The technologies necessary to real long-distance space travel are far more likely to appear incrementally than as a result of some huge politically-inspired push. The only thing that's likely to provide that sort of push at the moment is an incoming "dinosaur killer", and by the time that we've got twenty permanently-inhabited space stations, that is unlikely to be much of a real threat. Otherwise, it's the old "boiled frog" combination of overpopulation and overconsumption that are going to kill your species.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
  2. Hmmm... by chadplusplus · · Score: 2, Funny

    Ten light years away... How far out does the Oort cloud extend? Its NEMESIS!!

    1. Re:Hmmm... by tmosley · · Score: 2, Informative

      1/3rd of a light year. The brown dwarf is about 2.5 times further than the nearest bright star, Alpha Centauri. Definitely not inside of the solar system, but well within our cosmic neighborhood.

    2. Re:Hmmm... by chadplusplus · · Score: 4, Interesting

      Well, according to wikipedia, the largest estimates put the Oort cloud out at 3.6 light years, so this brown dwarf is probably too far away to perturb the Oort cloud, but as an aside observation: If the Sun's oort cloud is 3.5 light years in radius, and Proxima Centuari is only 4.2 light years away, and assuming Proxima Centuri has its own oort cloud (if it didn't get swept away by the gravitational interaction of the multiple stars), would our system's outer members and Proxima's outer members intermingle? IIRC, the Oort cloud objects aren't necessarily on the plane on the system.

    3. Re:Hmmm... by Albinoman · · Score: 2, Interesting

      The Oort cloud is a lot of minuscule particles of ices of different forms (not all water ice). If it were everywhere we'd surely notice this rather thick nebula permeating the universe. We wouldn't see Andromeda much less take the Hubble Deep Field.

  3. Cue the Nibiru quacks by Craig+Maloney · · Score: 4, Insightful

    Just waiting for the Nibiru and Planet X quacks to say "See? We told you so!".

    http://en.wikipedia.org/wiki/Nibiru_collision

    1. Re:Cue the Nibiru quacks by corbettw · · Score: 2, Funny

      Or why some kids think they won't live past their 21st birthday.

      I know one kid who won't live past his 13th birthday if he doesn't get his Math grade up!

      --
      God invented whiskey so the Irish would not rule the world.
    2. Re:Cue the Nibiru quacks by zeropointburn · · Score: 2, Interesting

      Don't let the next sentence scare you off.
        I have read the Bible from cover to cover, both King James and Strong's Concordance (though not all of the ridiculously exhaustive supplementary material in that one). Most of what I hear from modern Christians does not blend with what I took from those readings. This includes apocalypse beliefs. For starters, the Bible implies a period of 1,000 years for the end of Earth to take place (not that biblical time spans mean anything), and mentions several events that would be fairly obvious.

        Finding nearby objects of interest is worth hearing about. Having another stellar object that close is bound to be useful for astronomy. Consider this, though: if we could miss this brown dwarf until now (even using gravitational investigation), we could have missed one even closer. Since we have closer objects to visit, why don't we start with a probe (or a set of probes) to the Oort cloud? Let's get some more specific density and composition and orbit data on these things. Lots of ice? Cool, destabilize big chunks of it and send them to Mars or something. Long-term, obviously, but there is a lot that we do not know about that region of our solar system.

      --
      -1 raving lunatic; +6 subGenius... Things even out...
  4. Probably has water by Meshach · · Score: 4, Interesting
    FTA:

    Using the Gemini Observatory, follow-up spectroscopic analysis has detected methane and water vapor in its atmosphere

    I think that the discovery of water is very interesting. And with organic compounds existing there (in the liked article) this could be a very important discovery in our quest to understand the universe.

    --
    "Maybe this world is another planet's hell"
    Aldous Huxley
    1. Re:Probably has water by BJ_Covert_Action · · Score: 4, Interesting
      On top of that,

      It could have a surface temperature as low as 400 Kelvin, even cooler than the team's previous record of slightly below 500 K

      That's only ~127 Celsius, 27 degrees above water's boiling point. That temperature range is far from uninhabitable. Combine the organic compounds with methane and water and a relatively moderate surface temperature and I would say that we have a prime example of one very possible location for life outside of our own solar system. That's pretty damn exciting.

      --
      Motorcycles, Robots, Space Gossip and More!
    2. Re:Probably has water by Lord+Ender · · Score: 2, Insightful

      Hm? Wouldn't one expect a star to have a much denser atmosphere due to the high gravity?

      --
      A slashdotter who didn't build his own computer is like a Jedi who didn't build his own lightsaber.
    3. Re:Probably has water by Frequency+Domain · · Score: 3, Informative

      It's not a star . Brown dwarfs generate enough heat at their cores to maintain convection between the core and the surface, which keeps elements from differentiating (separating out), but they don't have enough mass to sustain fusion, which is required to be considered a star.

  5. It's going to get us! by SailorSpork · · Score: 2, Funny

    I like how the title implies that having "rogue" brown dwarf "lurking" close by is some sort of security threat. WATCH OUT, IT MAY HAVE WMD'S!!!!!111one

    I think we should greet it with open arms and set up McDonald's and Starbuck's franchises as soon as we can to show it that we welcome it as a neighbor!

    1. Re:It's going to get us! by MiniMike · · Score: 2, Funny

      I think we should greet it with open arms and set up McDonald's and Starbuck's franchises as soon as we can to show it that we welcome it as a neighbor!

      That will only greatly increase its mass and make it more dangerous!

  6. Gimli is in space? by DRAGONWEEZEL · · Score: 4, Funny

    He's the coolest brown dwarf I know of too, but how did he get out there?

    --
    How much is your data worth? Back it up now.
    1. Re:Gimli is in space? by swanzilla · · Score: 3, Funny

      He's the coolest brown dwarf I know of too...

      What you talkin' 'bout Willis?

      --
      0 = 1 + e^(Alt something)
  7. Pretty close... by Notquitecajun · · Score: 4, Informative

    This chart http://www.astro.wisc.edu/~dolan/constellations/extra/nearest.html lists the closest objects to earth. The brown dwarf (being a failed brown dwarf and found recently...howzabout calling it FAIL) is about the 12th closest object to our solar system.

  8. Re:Water Vapor and Methane by osu-neko · · Score: 2, Insightful

    Neither. They're saying it's the only brown dwarf to, well, let me just quote them:

    Oddly, when looking at the spectrum from UGPSJ0722-05, there is an anomalous absorption line (i.e. a particular wavelength in the electromagnetic spectrum that is missing) that cannot be explained by our current understanding of brown dwarfs. Perhaps the UKIRT has discovered a new breed of brown dwarf; a very cool object with some chemical in its atmosphere that absorbs infrared radiation at a wavelength of 1.25 micrometers.

    Aside from the expected water vapor and methane, they've found this other absorption line pointing to something new and different from previous brown dwarves.

    --
    "Convictions are more dangerous enemies of truth than lies."
  9. Re:Perception... by ShadowRangerRIT · · Score: 2, Funny

    I hate you, and wish to burn your newsletter.

    --
    $_ = "wftedskaebjgdpjgidbsmnjgcdwatb"; tr/a-z/oh, turtleneck Phrase Jar!/; print
  10. Closer Brown Dwarf than this... by jameskojiro · · Score: 2, Interesting

    Just wait till we start getting results back from WISE, we may find some Brown Dwarfs that are close than this and maybe even some that are gravitationally bound to our own sun making us a binary or trinary system....

    I think it would be cool if we found a brown dwarf closer than 1LY fron earth that we could use as a testing ground for interstellar probes.

    --
    Tsukasa: All I really want, is to be left alone...