Slashdot Mirror

← Back to Stories (view on slashdot.org)

Storm-like Activity Found on Brown Dwarfs

Posted by ryuzaki0 on from the since-my-gal-and-I-ain't-together dept.

Schwamm writes "Yesterday, scientists at NASA and UCLA announced that they had spotted storm-like activity on brown dwarfs, balls of gas larger than Jupiter and Saturn, but too small to burn hydrogen. These storms on the brown dwarfs make the Great Red Spot on Jupiter look like a 'small squall'. Here's another article at CNN."

19 of 23 comments (clear)

  1. Brown Dwarfs: Planets or Stars? by eggstasy · · Score: 2, Insightful

    So does this mean that Brown Dwarfs are more closely related to planets than to stars?
    I've always though of them as smallish, lukewarm stars myself, but I'm not a professional astronomer or anything.
    Does anyone out there have more info on this?
    What's the most widely accepted theory nowadays? Is it about to change?

    1. Re:Brown Dwarfs: Planets or Stars? by JetScootr · · Score: 2, Insightful

      From what the article said, make anything big enough, it becomes a star. If it ain't quite big enough, it's a brown dwarf. If it ain't even that big, it's a gas giant planet. The diff is only in how much gas comes together. Apparently, you could just as easily call it a mega-size, mega-hot planet, or call Jupiter a nano-dwarf star.

      --
      Pavlov wouldn't be so famous if he'd used a can opener instead of a bell.
    2. Re:Brown Dwarfs: Planets or Stars? by CheshireCatCO · · Score: 2

      The difference is exactly that: how we think they formed. Stars form in a gas cloud collapse, whereas giant planets form by first accreting a core from an accretion disk around a forming star. To the best of our current understanding, anyway.

      As it turns out, the same people who research brown dwarf atmospheres are also the ones who have a lot to say about exoplanet atmospheres. Moral: in terms of what we can observe, brown dwarfs are basically the same a giant planets.

    3. Re:Brown Dwarfs: Planets or Stars? by texchanchan · · Score: 2

      This is a first-class example of how named classes go only so far in describing reality. Apparently spherical gaseous objects in space occur in a variety of sizes. They can't be smaller than a certain size because the gas wouldn't have enough gravity to hold itself together.

      Depending on how big it is, it may be cold, warmish, warm, hot or BINGO! it might have enough mass to start fusing.

      This would be the boundary between "planet" and "star," but the slightly smaller than stellar ones still wouldn't be something you could imagine settling on.

      I'd like to know more about the ones that are just above the brown dwarf level. Could something have terrestrial/Jovian style weather (wind, clouds, hurricanes) and also be fusing inside? That would be cool (hot).

    4. Re:Brown Dwarfs: Planets or Stars? by p3d0 · · Score: 2

      Can't stars have storms?

      --
      Patrick Doyle
      I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
    5. Re:Brown Dwarfs: Planets or Stars? by texchanchan · · Score: 2

      Pay no attention to what I said and listen to Cheshire Cat, who sounds like he knows

    6. Re:Brown Dwarfs: Planets or Stars? by JetScootr · · Score: 1

      "great big whirls have little whirls
      that feed on their velocity
      and little whirls have lesser whirls
      and so on to viscosity"

      Once we get enough observations done, I'm sure we'll figure out a sequnce, like with stars themselves, in which substellar objects evolve - main sequence: in an accretion disk. Secondary sequence: solo but not quite enough to become a star? Other sequence: gawd-awful big accretion disk that allows the protoplanet to suck up enough matter to start glowing...
      All different kinda scenarios are possible, and given time, they'll observe gobs of them...it's just a matter of years of detections accreting enough data to build actuarial tables.

      --
      Pavlov wouldn't be so famous if he'd used a can opener instead of a bell.
    7. Re:Brown Dwarfs: Planets or Stars? by CheshireCatCO · · Score: 2

      Brown dwarfs actually have spectral classes: L and T. (For some reason, the voices in my head are saying there's an M, too. But they also told me to buy dotcom stock.) They don't really evolve much in time, since there is little or no fusion occuring. They just kind of cool.

    8. Re:Brown Dwarfs: Planets or Stars? by gangien · · Score: 1

      depends on what you consider a star and what you consider a planet.

    9. Re:Brown Dwarfs: Planets or Stars? by Squiffy · · Score: 1

      Right, M stars are full-fledged fusion burners, ranging from supergiants to main sequence dwarfs.

  2. Funniest thing I've seen all day by devphil · · Score: 2


    This quote from the article:

    "The astrophysicists needed some help understanding rain because it's not an important process in most stars."
    ("Most" stars...?!)

    I'm glad I'm not the only one mystified by our planet's weather. (Like, how come it only rains on the days I don't bring an umbrella?)

    The article is really cool, though, especially on the techniques they used as a starting point.

    --
    You cannot apply a technological solution to a sociological problem. (Edwards' Law)
  3. Understanding the Physics by puckhead · · Score: 1

    I understand intellectually what happens in stars but I find it easier to comprehend whats going on with brown dwarfs. Even though we're talking about heat enough for iron clouds and rain it's a system that's familiar. Interesting.

    --
    Watching Cowboy Bebop in my jammies, eating a bowl of Shreddies.
  4. Weather in brown dwarfs. by Christopher+Thomas · · Score: 3, Informative

    I'd like to know more about the ones that are just above the brown dwarf level. Could something have terrestrial/Jovian style weather (wind, clouds, hurricanes) and also be fusing inside? That would be cool (hot).

    Anything with a convective layer and a heat gradient should have weather, so yes, everything from moons-with-atmospheres on up through full-blown stars should have it.

    The convective layer in red dwarfs is much deeper than in more energetic stars like the sun, as they're cooler (convective layer stops when the star material gets hot enough for radiative transmission to be the dominant heat transfer mechanism). Both still have them, though.

    Winds and storms should be present aplenty, but clouds are a bit iffy. They should only happen where a phase transition is possible (e.g. from plasma to monatomic gas, and from monatomic gas to molecular gases). This would be right at or near the "surface" of a star (maybe deeper for a red dwarf).

    Weather patterns would be very different from conventional weather in layers hot enough to be plasma, as plasma interacts strongly with the star's magnetic field. This region would be anything below a certain depth (i.e. most of the convective layers) and in the corona, for an active star.

    Stars are neat :).

  5. Am I the only one... by antirename · · Score: 1

    Who is having a hard time visualizing iron rain?

    1. Re:Am I the only one... by Tablizer · · Score: 2

      (* Am I the only one who is having a hard time visualizing iron rain? *)

      "Don't step in any puddles, Billy, the family blow-torch is not working right now."

      --
      Table-ized A.I.
  6. Yup by ColGraff · · Score: 2

    "Stars are neat :)."

    Yes. Yes, they are.

    Especially compared to the alternative, which would be the rather unpleasant absence of stars.

    --
    I'm the stranger...posting to /.
  7. Related Link: Microbes and Terresterial Weather by kfsone · · Score: 1

    The BBC are running an article on a theory that microbes may play a significant part in terresterial weather patterns. If this theory pans out, it could offer a potentially interesting lead to the search for ET (or mET or uET, if you prefer =). If the Great Red Spot is being maintained by microbes, does that mean it actually qualifies as Space Acne?

    --
    -- A change is as good as a reboot.
    1. Re:Related Link: Microbes and Terresterial Weather by Squiffy · · Score: 1

      There's a book somewhere, I think it's James Gleick's book Chaos that discusses work showing how a system like the Great Red Spot can occur as a natural consequence of fluid mechanics.

    2. Re:Related Link: Microbes and Terresterial Weather by kfsone · · Score: 1

      Quite true, but it would be most interesting to know whether it is possible to determine the presence of microbial life in the Jovian atmosphere by detecting exact variations between the observed and predicted patterns?

      --
      -- A change is as good as a reboot.