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Brown Dwarf With Water Clouds Tentatively Detected Just 7 Light-Years From Earth

sciencehabit (1205606) writes Astronomers have found signs of water ice clouds on an object just 7.3 light-years from Earth — less than twice the distance of Alpha Centauri. If confirmed, the discovery is the first sighting of water clouds beyond our solar system. The clouds shroud a Jupiter-sized object known as a brown dwarf and should yield insight into the nature of cool giant planets orbiting other suns.

55 of 85 comments (clear)

  1. Is this the missing "dark matter"? by Anonymous Coward · · Score: 2, Insightful

    There was not enough mass in what we can see from the galaxies. And people came up with strange theories like dark matter.

    Now we have an (arguably not so super heavy, but nonetheless) object just around the corner. Could it be that there's no dark matter, but that simply the galaxies are full of these things?

    1. Re:Is this the missing "dark matter"? by Anonymous Coward · · Score: 1

      not likely as there is too much missing mass (5% is observable mass and 27% is dark matter) of the galaxy and these are small objects less than one tenth of the sun. Also, these are accounted for in the models of the galaxy

    2. Re:Is this the missing "dark matter"? by mister_playboy · · Score: 5, Informative

      No, the amount of missing matter is far to great to be contained in such small objects even if they were incredibly numerous.

      Consider the entire mass of the asteroid belt is estimated to be only 4% of the Moon's mass, and the Moon's mass is only 1/81 of the Earth's.

      Dark matter, meanwhile, is thought to have a total mass more than 5 times greater than that of normal matter.

      --
      Do what thou wilt shall be the whole of the Law ::: Love is the law, love under will
    3. Re:Is this the missing "dark matter"? by Anonymous Coward · · Score: 1

      Shouldn't have an impact on the mass estimation of other galaxies, so no.

    4. Re:Is this the missing "dark matter"? by Anonymous Coward · · Score: 1

      I'm pretty sure that's where Lando lives.

    5. Re:Is this the missing "dark matter"? by Anonymous Coward · · Score: 2, Informative

      Logic fail. Dark matter can be explained by such small objects if they are incredibly numerous. It's just math: divide the missing mass by the mass of one brown dwarf to get the number needed. If you want to disprove the brown dwarf explanation you need to explain why the number that is needed contradicts something.

    6. Re:Is this the missing "dark matter"? by Buggz · · Score: 5, Insightful

      Logic fail. Dark matter can be explained by such small objects if they are incredibly numerous. It's just math: divide the missing mass by the mass of one brown dwarf to get the number needed. If you want to disprove the brown dwarf explanation you need to explain why the number that is needed contradicts something.

      The hypothesized dark matter does not emit or absord any type of electromagnetic radiation, in other words it does not interfere with or react to light. Numerous small objects would. Also, and this is the most important bit in your logic fail fail, if you have enough small objects to account for five times the mass of the visible universe, you would have something five times more visible than the visible universe. Matter attracts other matter (which is why there is a dark matter hypothesis to begin with, something invisible attracts the visible) and such a copious amount of "small objects" would form larger objects. Which is how stars and planets form to begin with.

    7. Re:Is this the missing "dark matter"? by TapeCutter · · Score: 4, Interesting

      Exactly, we think of Jupiter as being huge but the Sun holds 98% of all the matter in our solar system. If the "missing mass" were normal cold matter, such a great quantity would effectively block the light of the stars we can see, astronomy would not exists because we wouldn't see anything except our own sun and moon.

      Similar inane arguments were aimed at Newton, plenty of 15th century scholars thought that the fact a bird can fly disproved the theory of gravity. We still don't know what the hell gravity is (other than a property of matter) but we no longer question it's existence and have developed a very good understanding of how it behaves. Dark matter is harder to wrap one's head around because it's effects can not be observed in everyday human experience. However the effects are real and the tag scientists have given them is "dark matter".

      --
      And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
    8. Re:Is this the missing "dark matter"? by joe_frisch · · Score: 4, Informative

      Its not a simple argument but if you look at:
      http://en.wikipedia.org/wiki/D...
      dark matter composed of bits of normal baryonic matter is not consistent with observations / simulations

    9. Re:Is this the missing "dark matter"? by TomGreenhaw · · Score: 1

      If there were that much normal matter out there we'd know because the light from distant galaxies would be more blocked than it is.

      --
      Greed is the root of all evil.
    10. Re:Is this the missing "dark matter"? by idji · · Score: 2

      No, MACHOs do not account for all the Dark Matter in the Universe.

    11. Re:Is this the missing "dark matter"? by Charliemopps · · Score: 2

      No, Dark matter does not interact with normal matter. We can "See" light and radiation pass unimpeded through areas that contain detected dark mater. It does not reflect, bounce off of or interact in any other way... except it's gravitational pull. That's why it's called "Dark" Moving light/radiation will bend around it, but not bounce off of it.

    12. Re:Is this the missing "dark matter"? by Drethon · · Score: 1

      At the moment, dark matter is just a place holder in equations to make the equations match observations. It remains to be seen if the placeholder will one day be observed or the equations need to be rewritten (if just slightly) to match actual observations.

    13. Re:Is this the missing "dark matter"? by LordLimecat · · Score: 1

      Whether it has or has not been eliminated, idle speculation isnt compelling. If you havent studied this and / or had extensive experience with it, you probably shouldnt be composing theories on dark matter.

    14. Re:Is this the missing "dark matter"? by Intrepid+imaginaut · · Score: 1

      Like dimples in space.

    15. Re:Is this the missing "dark matter"? by Rei · · Score: 1

      And how do magnets work, HMMM?????

      --
      Could chocolate let me finish?
    16. Re:Is this the missing "dark matter"? by Rei · · Score: 1

      Like letting the air out of a balloon!

      --
      Could chocolate let me finish?
    17. Re: Is this the missing "dark matter"? by caveqat101 · · Score: 1

      Restating your argument, only those with extensive knowledge of a subject are knowledgable enough to comment? There goes /..no more articles, better get the bible out and only use that for stellar research. You build a theory by standing on the shoulders of others and learning. Modifying the past learning to open the future learning. Otherwise you shut down learning. Learning is the asking of questions. To find a reason something exists or why, or gee, that's neat. That's why science should never be "settled", that means a new dark age. Remember, the bible settled all heracy, such as science, with death. Be a heritic, live,ask, learn.

    18. Re: Is this the missing "dark matter"? by geekoid · · Score: 1

      ". You build a theory by standing on the shoulders of others and learning."
      Yes. But if you don't even stand on the shoulders of the giants in a field, then you should probably shut the fuck up.

      "Learning is the asking of questions."
      Yes, but it isn't throwing out ideas so off base they aren't even wrong, and then telling people to show you why they can't be when the idea being stated makes no sense at all. AC who posted that question clearly doesn't know the first thing about dark matter. Frankly, the poster should have the decency to do some preliminary understanding of the problem before spouting off nonsense and then getting defensive about it.

      --
      The Kruger Dunning explains most post on /. http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect
    19. Re:Is this the missing "dark matter"? by Anonymous Coward · · Score: 2, Insightful

      No, they have not eliminated the possibility that dark matter does interact with electromagnetism weakly, which is the basis of some particle detection searches and some scans of the skies for things similar to antimatter-matter interactions. But they have pretty much eliminated that dark matter is dense piles of regular matter (e.g. brown dwarfs, or black holes, or rogue planets) by doing microlensing surveys which set an upper bound on the number of such objects. If there were enough to account for dark matter amounts required for rotation curve of galaxies, they would have seen way more microlensing events than they did. This applies regardless of evidence suggesting that dark matter is not baryonic (the same evidence points out that there is unseen regular matter too, which would mean there is stuff like this not yet observed that needs to be found before you would even start edging into the dark matter category).

    20. Re:Is this the missing "dark matter"? by PPH · · Score: 1

      We still don't know what the hell gravity is (other than a property of matter) but we no longer question it's existence and have developed a very good understanding of how it behaves.

      Maybe not so good. ts possible that dark matter is just a fudge factor tat we need to apply to Newton's inverse square law over larger distances or for larger masses.

      Here's an interesting thought puzzle: Assume the effects of gravity are caried by some yet to be discovered particle/wave (gravitons) and these 'particles' are subject to the same laws of physics that all other partices are (photons, for example). Then how do they escape the gravitational pull of a black hole? If photons can't get out, then how do these gravitons? If gravity exists as a wave, then why wouldn't the gravitational attraction of the black hole bend these waves back around into itself, preventing it's effects on neighboring matter

      --
      Have gnu, will travel.
    21. Re:Is this the missing "dark matter"? by rahultyagi · · Score: 1

      Here is something to boggle your mind. You think your argument is strong with Sun containing 98% of the Solar system's total mass? It is actually something like 99.8%!! to think that stray jupiter-size brown dwarves can weigh anywhere near the total stellar masses that we see betrays complete lack of understanding of the difference of scales involved.

    22. Re:Is this the missing "dark matter"? by Rockoon · · Score: 1

      the Sun holds 98% of all the matter in our solar system. If the "missing mass" were normal cold matter, such a great quantity would effectively block the light of the stars we can see

      This simply doesnt compute unless you make assumptions about the distribution of the missing mass, and in this case your argument assumes its distributed evenly (nebula) while also taking advantage of the fact that the actual visible mass (stars) isnt.

      Let me translate the flaw so you understand: You are claiming that there is no place to put 100 of these brown dwarfs near a star that wouldnt block the stars light from reaching any of the rest of the universe. (and before you go there, I didnt pull 100 out of my ass. I actually did the relative mass calculation. This brown dwarf is about 1/100th the mass of our star.)

      I am not arguing that there isnt good reason to believe that the missing matter cannot be baryons. I am arguing that your understanding of the real arguments is complete and utter bullshit and this explanation is complete and utter bullshit.

      Even under 100x magnification, the actual visible stars are unresolvable pinpricks of light. Billions of them literally cover ~zero area of the celestial sphere. Since billions of stars cover almost zero area of the sky, billions of smaller things also cover almost zero area of the sky. Their ability to block out the light of the universe is virtually zero unless we make a low-density assumption (such as what your argument does.) Yet in fact these brown dwarfs are 10 times as dense as our sun, the exact opposite of low density.

      The primary reason we exclude brown dwarfs like these as being the dark matter within the galaxies that effects its gravity is the lack of gravitational microlensing that such matter would cause. Its not at all the obstruction of light (that you theorize) as the reason, its the lack of bending of light.
      So not only is your theory wrong, its antithetical to the real reason. If we expected the proper amount of brown dwarfs that would explain dark matter to block light, we wouldnt be able to expect the microlensing we actually looked for.

      Now dont discuss this subject any more unless you learn at least a few basic things.

      --
      "His name was James Damore."
    23. Re:Is this the missing "dark matter"? by Viol8 · · Score: 1

      "Now dont discuss this subject any more unless you learn at least a few basic things."

      You should follow your own advice. Most brown dwarves are glowing away nicely in infrared. If there were triillions of them they'd be lighting up the sky in that band. They arn't, so unless something has cooled them all down to absolute zero (yeah, right), they don't exist. Back to school for you.

    24. Re:Is this the missing "dark matter"? by mod+prime · · Score: 2

      Yeah, I liked the MACHO idea many years ago, they may still account for some of the gravity yet, but the position is more or less untenable at this stage both empirically and theoretically.

    25. Re:Is this the missing "dark matter"? by x_t0ken_407 · · Score: 1

      No matter how cold it is, it would STILL interact with light (being cold does not make something invisible). And given the number of cold brown dwarfs it would take to make up the difference, it would be virtually impossible to NOT have seen them (if they were in fact the the culprits of dark matter) as others have alluded to in this thread.

    26. Re:Is this the missing "dark matter"? by Livius · · Score: 1

      No.

      Dark matter is matter that does not interact with electromagnetic forces. It isn't mass that's gone missing.

    27. Re:Is this the missing "dark matter"? by Livius · · Score: 1

      No, they have not eliminated the possibility that dark matter does interact with electromagnetism weakly

      If it's violating Maxwell's laws, then 1) whatever else it is it's not ordinary matter, and 2) that's far-fetched and cool the same way the dark matter hypothesis is.

    28. Re:Is this the missing "dark matter"? by Rob+Riggs · · Score: 1

      You think your argument is strong with Sun containing 98% of the Solar system's total mass? It is actually something like 99.8%!!

      Yep. Here's a good source for the relative masses of the solar system object: http://en.wikipedia.org/wiki/List_of_Solar_System_objects_by_size#List. It does not include the Oort Cloud, which is though to contain about 5 Earth masses of material.

      --
      the growth in cynicism and rebellion has not been without cause
    29. Re:Is this the missing "dark matter"? by TapeCutter · · Score: 1
      Yeah right, brown dwarfs spontaneously arranging themselves so we can conveniently see past them from earth is a very likely scenario. The paradox that you are relying on is that an infinite number of one dimensional points on a number line cannot get you from point A to point B. Stars are not one dimensional points but yes I quite likely exaggerated when I said only the moon and sun would be visible.

      Now dont discuss this subject any more unless you learn at least a few basic things.

      Your post was interesting and informative but my reaction to this parting shot is - go fuck yourself you arrogant son of a bitch.

      --
      And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
  2. First non-cloud candidate by mdsolar · · Score: 3, Interesting

    The abstract says "this is the first candidate outside our own solar system to have direct evidence for water clouds." Which is true in the sense that water in star spots is vapor and not condensed. However molecular clouds often have water ice in them and so might be considered water clouds if condensation is the criterion. This is cool discovery.

  3. Occam's razor. by TapeCutter · · Score: 3, Insightful

    Could it be that there's no dark matter, but that simply the galaxies are full of these things?

    Could it be that all the cosmologists and physicist who have been looking at this for a couple of decades somehow missed that blindly obvious "possibility". Or is it more likely you are simply unaware of the evidence that forces these people to dismiss the obvious "common sense" answer?

    --
    And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
    1. Re:Occam's razor. by Anonymous Coward · · Score: 1

      A better reply would have been "No, and here's why." Nice and all civil-like. Try it! You'll be surprised by its effectiveness.

    2. Re:Occam's razor. by Electricity+Likes+Me · · Score: 1

      I'd be un-surprised when it leads a half-dozen "gotcha" worded follow ups from someone who clearly has no interest in Googling their own ideas first.

    3. Re:Occam's razor. by smittyoneeach · · Score: 1

      tl;dr: "Welcome to /."

      --
      Get thee glass eyes, and, like a scurvy politician, seem to see things thou dost not.--King Lear
    4. Re:Occam's razor. by idji · · Score: 3, Interesting

      No, Astronomers have asked the WIMP vs MACHO question for many decades now, and WIMPs are winning.

      Occam's Razor has always been applied here, and that is why it is still an open question, because the simple and obvious answer (MACHO) is not working and extraordinary evidence is being found, eg the Physic's Nobel Prize 2011.

      This article is not about MACHO vs WIMP. It says they found a nearby MACHO with water vapor, and that is very interesting for life questions, not dark matter questions.

    5. Re:Occam's razor. by Anonymous Coward · · Score: 1

      Could it be that there's no dark matter, but that simply the galaxies are full of these things?

      Could it be that all the cosmologists and physicist who have been looking at this for a couple of decades somehow missed that blindly obvious "possibility".

      Because cosmologists are never finding anything new? Im not trying to stir anything up, especially since you seem to have an emotional stake on this topic.

    6. Re:Occam's razor. by TapeCutter · · Score: 2

      Very interesting but kind of irrelevant since the question I was addressing asked if brown dwarf could be the famous "missing matter". What we have actually observed is the effects of a gravitational field, precisely what is causing that field to manifest itself we don't know, but we have known for a long time it's not an overabundance of brown dwarfs.

      --
      And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
    7. Re:Occam's razor. by TapeCutter · · Score: 3, Insightful

      How was my reply "uncivil"? Blunt with just a hint of sarcasm certainly, but there's nothing in there that should offend someone who is genuinely interested in an answer. In fact I deliberately used the word "unaware" because "ignorant" is normally viewed as derogatory (even though it actually isn't).

      If you feel a gentler more informative answer can be provided then why not provide it? I'm sure the OP is quite capable of defending himself against my prose if it has unintentionally offended him in some way that I'm unaware of. What I'm not so sure of is why do you feel the need to be offended on his behalf?

      --
      And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
    8. Re:Occam's razor. by Sperbels · · Score: 1

      How about an overabundance of black holes?

    9. Re:Occam's razor. by coastwalker · · Score: 1

      Posters do not have to pander to idiots just to be civil. There is nothing wrong with a bit of boisterous prose.

      The associated subject of the impossibility of human interstellar travel is another one that people never admit

      Mind you it is a bit dull realizing that the human race is stuck in this solar system forever, never mind just for now.

      --
      Facts are history now plebs have politics for religion on social media.
  4. Is this the same brown dwarf that... by JasonGoatcher · · Score: 1, Offtopic

    Wants to know what Willis is talkin' bout?

  5. The theorized nemesis star? by Dukenukemx · · Score: 1

    It's been said that the sun might have a brown dwarf that orbits it. Seven light years isn't that far off.

    1. Re:The theorized nemesis star? by Overzeetop · · Score: 3, Interesting

      The brown dwarf that orbits the sun is called Jupiter.

      --
      Is it just my observation, or are there way too many stupid people in the world?
    2. Re:The theorized nemesis star? by Anonymous Coward · · Score: 1

      Seven light years is that far off. There's multiple star systems between us and it, which would interfere with it's orbit.

    3. Re:The theorized nemesis star? by Zephyn · · Score: 1

      There's a mass and temperature difference between gas giants and brown dwarf stars. The cutoff is whether the object in question has any fusion going on at all. At about 13x Jupiter mass it's big enough to fuse deuterium, and at 65x it can fuse lithium. If it's massive enough to fuse hydrogen, you've crossed into Red Dwarf territory (oh smeg!).

      No form of sustained fusion has ever been detected within Jupiter, so it's not a brown dwarf, just a gas giant planet.

  6. Going to Battle by gsslay · · Score: 1

    From the article;

    "I went to battle at the telescope to try and get this detection," Faherty says. "I wanted to put war paint under my eyes and wear a bandanna, because I knew this was not going to be an easy thing to do."

    Who said astronomy was dull? There has to be a TV series to had here. Action Astronomer wields her mighty War Telescope!

    1. Re:Going to Battle by pr0nbot · · Score: 1

      Episode 16: The missing TPS cover sheet

  7. Moons? by MichaelSmith · · Score: 1

    I wonder if it has any Earth sized moons. Maybe one close in could be kept warm(ish) by tidal heating.

    1. Re:Moons? by Rei · · Score: 3, Informative

      Indeed it does. I haven't published yet, but I detected one a few days ago (I work out of a valley in Iceland). I observed the brown dwarf in question (right ascension 08h 55m 10.83s, declination -07 14 42.5") and detected a large, earth-sized body occluding the star during my brief observations.

      --
      Could chocolate let me finish?
    2. Re:Moons? by Anonymous Coward · · Score: 1

      Ahhh ... Slashdot ... where some posts are impossible to differentiate between humor and sheer awesomeness.

    3. Re:Moons? by geekoid · · Score: 1

      Well, it's funny you say that.

      We saw two moons. One of which wasn't in earlier detections, and as it came around the brown dwarf, it just exploded. weird.

      --
      The Kruger Dunning explains most post on /. http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect
    4. Re:Moons? by NormalVisual · · Score: 1

      So I'm assuming the IAU will be naming it "REI-128717"? ;-)

      --
      Please stand clear of the doors, por favor mantenganse alejado de las puertas
    5. Re:Moons? by MichaelSmith · · Score: 1

      Its clearly a trap.

    6. Re:Moons? by MichaelSmith · · Score: 1

      Could that body have been... The Earth? The same thing happens whenever I try to look at Paris from Australia.