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Star Cooler Than Venus Found

Posted by ScuttleMonkey on from the miles-davis-of-stars dept.

crossconnects writes to mention that Discovery is reporting that astronomers have found a nearby star with a mild surface temperature of 660 degrees fahrenheit. "The spectacularly unspectacular object is of special interest because it falls right smack in the middle of the final frontier that divides mega-planets from the puniest stars. Stars in that realm theoretically qualify as an entirely new stellar type -- what's called a Y class dwarf."

55 comments

  1. whoa by Anonymous Coward · · Score: 0

    holy shit

  2. Not that hard by 0racle · · Score: 5, Funny

    Venus never was that hip.

    --
    "I use a Mac because I'm just better than you are."
    1. Re:Not that hard by riskeetee · · Score: 5, Funny

      Agree, Serena's hotter.

    2. Re:Not that hard by sconeu · · Score: 1

      I always thought the Sun was much cooler, too.

      Venus just sits there, and greenhouse collects heat, while the Sun is essentially this ginormous H-bomb!
      Come on, which is cooler? A bomb, or a passive collector of heat?

      --
      General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
  3. Publication at arXiv.org by Jugalator · · Score: 5, Informative
    Here's the actual publication on the discovery:
    http://arxiv.org/abs/0802.4387

    ... or straight to the PDF:
    http://arxiv.org/pdf/0802.4387v2

    --
    Beware: In C++, your friends can see your privates!
  4. impossible! by Anonymous Coward · · Score: 0

    Female dwarf?

  5. Nuclear fusion? by smolloy · · Score: 5, Interesting
    I thought the definition for a star was that there had to be fusion occurring at its core. TFA doesn't mention it, but I'm amazed that this object can be this cool, yet still have a nuclear furnace at its heart.

    Fascinating stuff indeed.

    1. Re:Nuclear fusion? by Jugalator · · Score: 1, Redundant

      I agree, that was what surprised me the most and I was also surprised the article didn't mention that, because to me that's not what I would have expected in this case.

      --
      Beware: In C++, your friends can see your privates!
    2. Re:Nuclear fusion? by Tenebrousedge · · Score: 5, Informative

      Stars above about 13 jupiter masses fuse deuterium and above 65 jupiter masses also fuse lithium, according to Wikipedia. Below 13 jupiter masses, well, it's hard to say...

      --
      Those who advocate genocide deserve every protection afforded by law, and none afforded by common human decency.
    3. Re:Nuclear fusion? by Sique · · Score: 2, Informative

      If you don't have much fusion, and not very much convection within the star, then the heat gets to the surface very slowly (it can take up to billions of years!), and distributed along the while surface the energy stream is low.

      --
      .sig: Sique *sigh*
    4. Re:Nuclear fusion? by Ironsides · · Score: 3, Funny

      TFA doesn't mention it, but I'm amazed that this object can be this cool, yet still have a nuclear furnace at its heart.

      Perhaps it's using cold fusion? (ba dump dum)

      --
      Fly me to the moon Let me sing among those stars Let me see what spring is like On jupiter and mars
    5. Re:Nuclear fusion? by g0dsp33d · · Score: 4, Funny

      Or physicists can do what they usually do and discover "dark" fission.

      --
      lol: You see no door there!
    6. Re:Nuclear fusion? by DreadPiratePizz · · Score: 1

      That's not in the definition. White dwarf stars are only radiating accumulated heat. There's no fusion going on, but they are still stars.

  6. Cool! by Anonymous Coward · · Score: 0

    Cool!

    1. Re:Cool! by calebt3 · · Score: 0, Redundant

      Literally (for a star)

  7. Sigh, Bad English / Hmm - Biosphere? by TexVex · · Score: 5, Interesting

    FTA: That means any water in there atmospheres will condense into droplets of water vapor

    Aside from the bad English, the quoted bit is actually the most interesting part of the article. Does that mean that a particularly low-temp one of this newly discovered kind of dwarf star could be a self-contained biosphere, with a source of heat in the center surrounded by a life-sustaining atmosphere with liquid water in it?

    Dyson Sphere is to Ringworld as Cool Dwarf is to Smoke Ring! :)

    --
    Fun with Anagarams! LADS HOST, SHALT DOS. HAS DOLTS. AD SLOTHS, HATS SOLD. ASS HO, LTD.
    1. Re:Sigh, Bad English / Hmm - Biosphere? by RobertB-DC · · Score: 0, Redundant

      The bad English is sad -- you would think that they'd employ a copy editor.

      But that wouldn't do anything to prevent using that image and caption. The image is of something bizarre, a red planet-looking thing with something spouting from the poles. It looks more like a candy in a clear plastic wrapper than an extra-cold star.

      And the caption is even worse. Put a picture of a red candy with the caption "Ambiuguous Star", and I'm not thinking astronomy. I'm thinking Katamari. Royal Rainbow!

      --
      Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
    2. Re:Sigh, Bad English / Hmm - Biosphere? by Anonymous Coward · · Score: 0

      Wow, gay bashing!

      That's so funny and hip! Boy, XKCD you've really outdone yourself.

    3. Re:Sigh, Bad English / Hmm - Biosphere? by IndustrialComplex · · Score: 2, Insightful

      While the conditions are almost there for life similar to that of Earth to develop, the problem is that there are a lot of 'almosts', and I'm willing to bet that almost won't cut it in this case.

      Just two of the things that would probably cause problems is that it is likely a very turbulent atmosphere when compared to that of Earth, and of course, there is also the likely high amount of radiation that is bouncing around (it is a star after all).

      If we are thinking DNA/RNA based life, the radiation involved would make it very hard to reproduce.

      As I type this more and more obstacles are coming to light, but I couldn't imagine a situation in which life could occur on a star.

      --
      Out of modpoints but really liked a post? 1BDkF6TtmmeZ3yqXbz9yhdYVqRYnwFoXDj
    4. Re:Sigh, Bad English / Hmm - Biosphere? by SQLGuru · · Score: 1

      Re: a lot of radiation

      So, you're saying it's a biosphere of roaches, then....?

      Layne

    5. Re:Sigh, Bad English / Hmm - Biosphere? by strack · · Score: 2, Interesting

      Radiation? The only radiation source is fusion at the core of the star, The only thing this star radiates is Infrared. i.e. Heat. to get any ionizing radiation, youd prolly have to be near the core. It probably looks like a particularly active really big gas giant.

    6. Re:Sigh, Bad English / Hmm - Biosphere? by IndustrialComplex · · Score: 2, Informative

      That is a good point, I forgot that it is mostly infrared radiation. However, just because there is no visible light, does that mean it is generating no radiation above the visible spectrum? I'm assuming that this star is fusing Deuterium and Tritium, which I believe does produce Gamma Rays.

      Brown dwarfs have been observed to produce X-rays and Gamma rays. So just because this one produces no visible light does not mean it isn't producing a large amount of high energy radiation.

      --
      Out of modpoints but really liked a post? 1BDkF6TtmmeZ3yqXbz9yhdYVqRYnwFoXDj
    7. Re:Sigh, Bad English / Hmm - Biosphere? by sjames · · Score: 1

      while the conditions woud be extreme, there is Earth life that lives in and around volcanic vents and there are bacteria that are resistant to radiation. If the surface is *only* 660C, there's not a lot of fusion going on and there's likely a very thick and dense shield between the barely fusing core and the surface, so life is not entirely out of the question.

    8. Re:Sigh, Bad English / Hmm - Biosphere? by IndustrialComplex · · Score: 1

      while the conditions woud be extreme, there is Earth life that lives in and around volcanic vents and there are bacteria that are resistant to radiation. If the surface is *only* 660C, there's not a lot of fusion going on and there's likely a very thick and dense shield between the barely fusing core and the surface, so life is not entirely out of the question.


      That is true, however I think it is important to note that the expectation is that life did not originate from the area surrounding those volcanic vents. The theory is that life originated elsewhere, and then evolved/adapted to live around the volcanic vents. Now, where I think we could have an interesting discussion, is if the conditions in the lower atmosphere of this star approximate the conditions of the deep sea volcanic vents on Earth.

      My expectation, however, is that while this star is of a similar temperature to these volcanic vents on its outer layers, the pressure isn't great enough to force the water vapor into liquid water. As you go lower in the atmosphere of this star, the pressures would increase quickly, but unfortunately I think that the temperature would rise at a higher rate due to the high density of this star when compared to a planet like Jupiter.

      The result is that the point where you might find liquid water at a temperature low enough to avoid ripping apart DNA or DNA-like molecules would be a very narrow band.

      Now, it is easier to be an armchair skeptic, so don't let that stop the discussion. We ARE dealing with a star here, and what might be a 'narrow' band on a stellar (jovian?) scale, could quite well be a massive section if you look at it from a terran scale.

      (and of course, this all assumes that we are considering DNA/RNA based life.)

      --
      Out of modpoints but really liked a post? 1BDkF6TtmmeZ3yqXbz9yhdYVqRYnwFoXDj
    9. Re:Sigh, Bad English / Hmm - Biosphere? by sjames · · Score: 1

      I'll certainly agree that the odds are truly miniscule and that if there is life there, it would be strange even compared to the extremophiles on Earth.

      I suppose I'm speculating without expectation, sort of the way Niven liked to imagine very odd but habitable worlds.

      If, indeed there are stars a couple hundred degrees cooler still, then it becomes more probable, but still with the problem of how would it evolve in the first place.

      Your suggestion that a habitable band would be deeper in is a good one, but I'm not sure how to calculate temperature vs. pressure gradient to see if there is a liquid water one and if so how thick.

  8. Fahrenheit by duffel · · Score: 0, Troll

    Fahrenheit is a rather silly temperature scale for stars, no?

    1. Re:Fahrenheit by drik00 · · Score: 1, Flamebait

      no.

      Fahrenheit is much funner to say than Celsius, or *wretch* Centigrade.... those sound like crap.

      J

      --
      Beer, now there's a temporary solution -- Homer Jay S.
    2. Re:Fahrenheit by amRadioHed · · Score: 3, Insightful

      No, not when audience is the American public.

      --
      We hope your rules and wisdom choke you / Now we are one in everlasting peace
    3. Re:Fahrenheit by treeves · · Score: 3, Funny

      What, they should have used Rankine?

      --
      ...the future crusty old bastards are already drinking the Kool-Aid.
    4. Re:Fahrenheit by servognome · · Score: 2, Informative

      Even with an American audience at the temperatures discussed Fahrenheit has no real meaning.
      The usefulness of Fahrenheit is how the range of 0 - 100 reflects weather temperatures people have experienced.
      Temperatures beyond common experience are better expressed in Celsius.

      --
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    5. Re:Fahrenheit by Jugalator · · Score: 2, Insightful

      Even if it's the scientific American public?

      --
      Beware: In C++, your friends can see your privates!
    6. Re:Fahrenheit by duffel · · Score: 3, Funny

      Then we should use Degrees Delisle, which has the added bonus of going backwards. Body temperature is at 95 Delisle. The sun (ours, that is) is at negative several thousand degrees Delisle.

    7. Re:Fahrenheit by Anonymous Coward · · Score: 1, Insightful

      Kelvin is the best.

    8. Re:Fahrenheit by duffel · · Score: 2, Interesting

      What, they should have used Rankine? Well, in the context, it makes about as much sense as the Kelvin scale... an arbitrary step size with absolute zero being the zero point. Sounds sensible to me! Probably would be better than Celsius or Fahrenheit. Alas, Kelvin got there ten years earlier, so it's the Celsius scale's step size for the accepted absolute scale. Still a bit arbitrary. Perhaps we should come up with a new scale that encompasses absolute zero and a very well defined temperature that makes sense on an absolute/astronomical level? Perhaps a logarithmic scale? Any ideas?
    9. Re:Fahrenheit by Jonathunder · · Score: 2, Insightful

      In a scientific article, I would expect stellar temperatures to be given in Kelvins.

      In a popular article, Celsius or Fahrenheit (depending on country) are probably expected and more understandable to a general audience.

      Ideally, any good article would give the measurement or estimate in the original units first (and with the original degree of precision), followed by a conversion if needed for the expected audience.

    10. Re:Fahrenheit by Anonymous Coward · · Score: 0

      Especially when it's the scientific American public. (because they assume any temperature figure is in farenheit *anyway* - anyone got the spec-sheet for this rocket booster I got for my mars lander?)

    11. Re:Fahrenheit by jd · · Score: 3, Interesting

      The "temperature" of the Big Bang is the theoretical hottest you can ever get, since at that point all mass was in the form of energy, and therefore you had the maximum energy at the maximum density. Nothing can ever exceed that. Thus, if you knew what that was, you could assign it a fixed value as your upper end of the scale. The ideal would be to then have a set of functions (linear, logarithmic, whatever), where a given function was selected for a specific type of application, with the exception of some specific function chosen as the 'standard'.

      --
      It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
    12. Re:Fahrenheit by amRadioHed · · Score: 2, Insightful

      600 F has no meaning? The dial on my oven goes up to 600 degrees. It's also the temperature gasoline ignites at. We are hardly talking about astronomical temperatures beyond our comprehension.

      --
      We hope your rules and wisdom choke you / Now we are one in everlasting peace
    13. Re:Fahrenheit by amRadioHed · · Score: 1

      Correction, gas ignites at 500, but my oven still goes up to 600.

      --
      We hope your rules and wisdom choke you / Now we are one in everlasting peace
    14. Re:Fahrenheit by Raineer · · Score: 1

      I agree with that, best post in the silly temperature units argument, mod parent up ^^

    15. Re:Fahrenheit by ultranova · · Score: 2, Informative

      The "temperature" of the Big Bang is the theoretical hottest you can ever get, since at that point all mass was in the form of energy, and therefore you had the maximum energy at the maximum density. Nothing can ever exceed that.

      Since the volume of space at t=0 was zero, but the energy content was not, the temperature at t=0 is infinite. That isn't useful for determining a scale. Alternatively, if the energy content was zero, then the temperature is lim(x->0) x/x, which is 0. If energy is zero but volume is nonzero, then temperature is 0/x (x>0), which is also 0. And if both volume and energy are nonzero, then you get a very large but finite amount, which is exceeded by classical black holes, where singularity has zero volume but nonzero energy content.

      This is, of course, all assuming that neither volume nor energy can be (were not) negative, since if they are, you get all kinds of extra nastiness.

      Thus, if you knew what that was, you could assign it a fixed value as your upper end of the scale.

      How do you define this numerical value ? How are you going to make such a scale any less arbitrary than Kelvin scale ?

      I propose an alternative: since temperature is determined by the average kinetic energy of a particle, use that as a gauge: at the temperature of 1 base unit, the average kinetic energy per particle is 1 Joule.

      Alternatively, use the blackbody radiation: the base unit corresponds to the temperature of a blackbody object who's peak of radiation has wavelength of 1 meter.

      --

      Forget magic. Any technology distinguishable from divine power is insufficiently advanced.

    16. Re:Fahrenheit by jd · · Score: 1
      That assumes a singularity at t=0, which Professor Hawking has provided a convincing case against. (As t approaches 0, space/time becomes parabolic, which means there is no requirement for a discontinuity and no requirement for a point of creation. He's usually quoted as having said that he's glad Pope John Paul - whom he visited shortly after giving that particular talk - had not heard that particular result at that time.)

      It also assumes it's useful to go back to a t=0, assuming one exists. Theoretical models can't usefully go back much further than the point immediately prior to the inflationary universe model kicking in. Since nothing before this point makes any difference to what happens after, we can use this point as the "Big Bang", which means we definitely have non-zero space.

      --
      It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
    17. Re:Fahrenheit by pla · · Score: 1

      but the energy content was not, the temperature at t=0 is infinite.

      Okay, at time t= +e(psilon), wiseguy. :).

      Of course, this quantity already goes by the name "Planck temperature", so we have a nice tidy number: 1.417 x10^32 Kelvin.


      How are you going to make such a scale any less arbitrary than Kelvin scale

      Well, any value on that scale gives a meaningful number in the sense that it expresses the portion of the maximum energy possible in this universe, with a well-behaved upper (100) and lower (0) bound.

      Of course, on the down side, we'd have to use microyoctodegrees to measure temperatures in our everyday range of experience, with water freezing at 193myD and boiling at 263myD.


      use the blackbody radiation: the base unit corresponds to the temperature of a blackbody object who's peak of radiation has wavelength of 1 meter.

      Not a bad idea, but that just gives you the identity of Wein's law, or 2.898K. Not really all that bad as a base unit for scientific purposes, but it puts water in a range of 94.2 to 128.7... Still not all that great for expressing everyday temperatures.

    18. Re:Fahrenheit by cobaltnova · · Score: 1

      The "right" unit of temperature measurement would be eV, or the Planck system of units. That's right: units of energy. It gives twice the average energy per degree of freedom of an object at said temperature. In this system, the Boltzmann constant would be equal to 1, as it should be and would have been had we known chemistry before coming up with the idea of "temperature".

      Room temperature is about 1/40 eV on this scale, or 25.3 meV. Water boils at 32.2 meV and freezes at 23.5 meV. Absolute zero is, of course, 0 meV.

    19. Re:Fahrenheit by Anonymous Coward · · Score: 0

      Well then, I suggest that you refrain from putting gasoline cans into your oven....*;)

    20. Re:Fahrenheit by jemtallon · · Score: 1

      I say we use 0 for absolute 0 and 1 for the Planck temperature. Then the weather difference here in North Dakota, from one day to the next would be so small that it wouldn't seem daunting. I'd feel much better with a 1.2x10^32 temperature drop than a 50 degree drop.

    21. Re:Fahrenheit by jemtallon · · Score: 1

      Make that a 1.2x10^-32 temperature drop ;)

  9. Cool by davidwr · · Score: 0, Redundant

    Seriously, this is interesting.

    --
    Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
  10. I'm one of Venus' best friends... by Anonymous Coward · · Score: 3, Funny

    ... and I have a hard time believing there are many stars out there that are even "as cool" as Venus. Venus is so fucking awesome that it's just absurd for anybody to claim they've found a star cooler than her.

  11. your anagram by crossconnects · · Score: 1

    lads shot, last shod, lost dash, halts sod

    --
    no big sig
  12. After... by RiyazShaikh · · Score: 1

    ... venus added Uranus as a friend on its My Space profile.

    1. Re:After... by LordSkippy · · Score: 1, Funny

      Professor Hubert Farnsworth: I'm sorry, Fry, but astronomers renamed Uranus in 2620 to end that stupid joke once and for all.

      Fry: Oh. What's it called now?

      Professor Hubert Farnsworth: Urrectum.

      --
      My karma is in a nose dive
  13. Discovery Channel's Target Audience != Scientists by GradiusCVK · · Score: 3, Insightful

    To some degree, you are correct; American scientists, the target audience of the original publication, would prefer the Kelvin unit, which was indeed used in the original publication. However, I don't think the Discovery channel's target audience is primarily scientists but rather the American public, which prefers Farenheit - hence the use of that unit on the Discovery channel's website (the location of TFA).

  14. Plank's Temperature by maz2331 · · Score: 1

    Planck's temperature is theoretically the hottest anything can possibly be at - 1.41679 X 10^32 K. Beyond that, and the energy density will basically generate enough gravity that it collapses into a black hole. (We're talking "Big Bang" energy density here.)

    Mater == energy, energy == matter, and enough of either in a small enough volume will collapse into a singularity.

    So - if you want a possible temp scale, use 0K as starting point, Planck temperature at end, and add convenient subdivisions. But, remember, the resulting "degrees" will still be arbitrary.