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Brown Dwarf Hits Record Low

Posted by Soulskill on from the bring-a-jacket dept.

astroengine writes "The Keck II infrared telescope on Mauna Kea, Hawaii, has spotted what appears to be the coldest brown dwarf ever detected. Astronomers from the University of Hawaii have managed to constrain its temperature to just shy of 100 degrees Celsius. The object is part of a brown dwarf binary system and is estimated to be 6-15 times the mass of Jupiter. This is an exciting object as it could belong to a so-far theoretical 'Y' class of brown dwarf, a classification that makes objects like this cool example more planet-like than star-like."

8 of 97 comments (clear)

  1. So maybe they can find water on it? by tomhudson · · Score: 5, Interesting

    After all, at the pressures we're talking about, water would be liquid well above 100 degrees C.

    1. Re:So maybe they can find water on it? by tomhudson · · Score: 3, Interesting

      Depends on what part of Venus. The surface will melt lead, and there's no plate tectonics (lack of water as a lubricant) because all the H2O is locked up in sulfuric acid clouds. One of the consequences of a locked crust is the inability to recycle the plates (and the chemicals like CO2 that they've pulled out of the atmosphere) via subduction.

    2. Re:So maybe they can find water on it? by Anonymous Coward · · Score: 2, Interesting

      I was thinking about this also. Due to the pressure at the surface water would clearly be a liquid, however it would be pulled down toward the core as it would be heavier then the gasses that make up a star. At some point the temperature would increase enough that it would turn it to steam. If the steam rose (which I don't think would happen as steam would still be more dense then hydrogen and helium) to a point where it would condense, it would actually be raining inside the star,

    3. Re:So maybe they can find water on it? by tomhudson · · Score: 3, Interesting
      You can't. Even if you nuked it to the point of turning portions to liquid, it wouldn't work. Liquids would release their CO2 into the atmosphere, and solids just won't subduct, because the rest of the crust is still locked together like interlocking pieces of a jigsaw puzzle.

      You could put a big-enough planet-killing asteroid into it, strip off the sulphur-dioxide-laden atmosphere, and start over, but the entire surface would be molten at that point, and since the rest of the planet is already "squeezed bone dry", you'd just end up back where you started when things cooled down enough.

      Dehydrating a planet looks to be like a one-way process.

    4. Re:So maybe they can find water on it? by Mr.+Slippery · · Score: 3, Interesting

      You could put a big-enough planet-killing asteroid into it, strip off the sulphur-dioxide-laden atmosphere, and start over, but the entire surface would be molten at that point, and since the rest of the planet is already "squeezed bone dry", you'd just end up back where you started when things cooled down enough.

      Comets, then? Big ol' chunks of ice from space.

      There's some interesting speculation about terraforming Venus in the wik: Terraforming of Venus.

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  2. what if there are a lot of these? a heck of a lot? by circletimessquare · · Score: 5, Interesting

    we look up at the night sky and see only the bight stars, and assume everything else is vacuum. what if there is a relationship on the order of 100 invisible brown dwarf/ orphan jupiter planetary systems for every regular star system? or 1,000/1 or 10,000/1 or 100,000/1 or more?

    i bet as we get better at trying to find exoplanets, we also find a lot of dead dark planetary systems out there. gravitationally bound, but completely without light. a jupiter, just sitting there all alone in the void, with its assemblage of moons/ planets, frozen, and without any light... but not rare at all, all over the place in fact and much more numerous than familiar ignited and main sequence star systems

    i mean, star creation should assume a gaussian distribution in terms of star size, right? doesn't that just make simple entropic sense? well look at the wide base of that gaussian curve, below the minimum size needed for ignition: its huge! in overall mass and in number. so if the size spread of star systems is truly gaussian, then there should be orders of magnitude more dark systems out there than ignited systems. i bet we find legions of these systems, or, rather infer legions of them, and just never know for sure, because, of course, they are pitch dark and energetically completely dead

    occlusion of other star systems would be the only way to see them. and even then, since they are so small and so far away, and occlusion would be once and probably not ever again, they would be much harder to find than exoplanets, unless they were close to our solar system. they would just become noise in the number of photons hitting earth

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    intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
  3. Dyson spheres? Ringworlds? by wisebabo · · Score: 3, Interesting

    So if the Keck telescope is sensitive enough to detect a (star? large planet?) sized object that is radiating at only at 100c, could it pick up Dyson Spheres? Ringworlds? (But perhaps ringworlds would be more easily detected using transit studies! And, yes I know that they are dynamically unstable!)

  4. Re:what if there are a lot of these? a heck of a l by circletimessquare · · Score: 3, Interesting

    i am not describing any of those things. i understand the debate about matter and dark matter and other exotic things we can't see in the universe, and a number of exotic possibilities about where "missing" matter might or might not exist

    but i am talking about a more mundane, simplistic issue about star formation and the possibility of a huge amount of "failed" star systems out there

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    intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it