Loading ...
Sorry, an error occurred while loading the content.

Re: Yahoo! News Story - Missing Link Between Planets and Stars Found - Yahoo! Ne

Expand Messages
  • mahtezcatpoc
    ... http://news.yahoo.com/s/space/20080410/sc_space/missinglinkbetweenplanetsandstarsfound ... I ll try to get right-ascension, declination and zodiacal
    Message 1 of 2 , Apr 18, 2008
    • 0 Attachment
      --- In thefixedstars@yahoogroups.com, Mark Andrew Holmes
      <mahtezcatpoc@...> wrote:
      >
      >
      > Mark Andrew Holmes (mahtezcatpoc@...) has sent you a news article.
      > (Email address has not been verified.)
      > ------------------------------------------------------------
      > Personal message:
      >
      >
      >
      > Missing Link Between Planets and Stars Found - Yahoo! News
      >
      >
      http://news.yahoo.com/s/space/20080410/sc_space/missinglinkbetweenplanetsandstarsfound
      >

      I'll try to get right-ascension, declination and zodiacal coordinates
      for this object.


      Mark A. Holmes




      Begin story.--

      Missing Link Between Planets and Stars Found

      SPACE.com Staff

      SPACE.com Thu Apr 10, 2:16 PM ET

      Brown dwarfs are the oddballs of the cosmos, more massive than planets
      but not heavy enough to generate the thermonuclear fusion that powers
      real stars. Now astronomers have found the coldest brown dwarf to date.


      The failed star might represent a new class of objects that are a
      missing link between planets and stars.

      The cold brown dwarf floats freely in space, not bound to a star. Its
      mass is somewhere between 15 and 30 times that of Jupiter. And it is
      about 660 degrees Fahrenheit (350 Celsius), cooler than any other
      known object in its class.

      The surface of the sun is about 11,000 degrees F (6,000 degrees C).
      The temperature at the top of Jupiter's clouds is about -230 degrees F
      (-145 degrees C), though at its core the mercury soars to 3,000
      degrees F (24,000 degrees C).

      The brown dwarf, named CFBDS J005910.83-011401.3, is about 40
      light-years from our solar system. It was found by an international
      team using the Canada France Hawaii Telescope and Gemini North
      Telescope, both located in Hawaii, and the a European Southern
      Observatory telescope in Chile.

      Oddballs

      The mass of brown dwarfs is usually less than 70 Jupiter masses. In
      contrast to a star like our sun, which spends most of its lifetime
      burning hydrogen and keeping a constant internal temperature, a brown
      dwarf spends its lifetime getting colder and colder.

      The first brown dwarfs were detected in 1995. Since then, they have
      been found to share common properties with giant planets, while
      differences remain. For example, clouds of dust and aerosols, as well
      as large amounts of methane, were detected in the atmospheres of the
      coolest brown dwarfs, just as in the atmosphere of Jupiter and Saturn.

      However, there were still two major differences. In the brown dwarf
      atmospheres, water is always in gaseous state, while it condenses into
      water ice in giant planets; and ammonia has never been detected in the
      brown dwarf, while it is a major component from Jupiter's atmosphere.

      Cooler still

      The newly-discovered brown dwarf looks much more like a giant planet
      than the known classes of brown dwarfs, both because of its low
      temperature and because of the presence of ammonia.

      To date, two classes of brown dwarfs have been known: the L dwarfs
      (temperature of 2,100 to 3,600 Fahrenheit (1,200-2,000 C), which have
      clouds of dust and aerosols in their high atmosphere, and the T dwarfs
      (temperature lower than 2,100 F), which have a very different spectrum
      because of methane forming in their atmosphere.

      Because it contains ammonia and has a much lower temperature than do L
      and T dwarfs, CFBDS0059 might be the protoype of a new class of brown
      dwarfs to be called the Y dwarfs, the researchers propose. This new
      class would become the coldest stellar objects, hence the missing link
      toward giant planets.

      Almost a planet

      This discovery also has important implications in the study of
      extrasolar planets.

      The atmosphere of brown dwarfs looks very much like that of giant
      planets, therefore the same models are used to reproduce their
      physical conditions. Such modeling requires to be constrained with
      observations. Observing the atmospheres of extrasolar planets is
      indeed very hard because the light from the planets is embedded in the
      much stronger light from their parent star. Because brown dwarfs are
      sometimes isolated bodies, with no stars nearby, they are much easier
      to observe.

      So looking to brown dwarfs with a temperature close to that of the
      giant planets will help in constraining the models of extrasolar
      planets' atmospheres, the researchers said.

      The discovery, led by researchers at Observatoire de Grenoble in
      France, the Canada France Hawaii Telescope, the University of Ottowa
      and other institutions will be detailed in the journal Astronomy &
      Astrophysics.


      --End story.
    • mahtezcatpoc
      ... http://news.yahoo.com/s/space/20080410/sc_space/missinglinkbetweenplanetsandstarsfound ... http://www.sciforums.com/showthread.php?t=79642 Position(2000):
      Message 2 of 2 , Apr 18, 2008
      • 0 Attachment
        --- In thefixedstars@yahoogroups.com, "mahtezcatpoc"
        <mahtezcatpoc@...> wrote:
        >
        > --- In thefixedstars@yahoogroups.com, Mark Andrew Holmes
        > <mahtezcatpoc@> wrote:
        > >
        > >
        > > Mark Andrew Holmes (mahtezcatpoc@) has sent you a news article.
        > > (Email address has not been verified.)
        > > ------------------------------------------------------------
        > > Personal message:
        > >
        > >
        > >
        > > Missing Link Between Planets and Stars Found - Yahoo! News
        > >
        > >
        >
        http://news.yahoo.com/s/space/20080410/sc_space/missinglinkbetweenplanetsandstarsfound
        > >
        >
        > I'll try to get right-ascension, declination and zodiacal coordinates
        > for this object.
        >


        http://www.sciforums.com/showthread.php?t=79642


        "Position(2000): RA 00:59:10.903, Dec -01:14:01.13"

        13 Aries 57, in Cetus, just west of 20 Ceti right above the Whale's
        tail, not far from the border with Pisces.


        I'm going to call this one Y Star Prototype.


        Mark A. Holmes




        > Begin story.--
        >
        > Missing Link Between Planets and Stars Found
        >
        > SPACE.com Staff
        >
        > SPACE.com Thu Apr 10, 2:16 PM ET
        >
        > Brown dwarfs are the oddballs of the cosmos, more massive than planets
        > but not heavy enough to generate the thermonuclear fusion that powers
        > real stars. Now astronomers have found the coldest brown dwarf to date.
        >
        >
        > The failed star might represent a new class of objects that are a
        > missing link between planets and stars.
        >
        > The cold brown dwarf floats freely in space, not bound to a star. Its
        > mass is somewhere between 15 and 30 times that of Jupiter. And it is
        > about 660 degrees Fahrenheit (350 Celsius), cooler than any other
        > known object in its class.
        >
        > The surface of the sun is about 11,000 degrees F (6,000 degrees C).
        > The temperature at the top of Jupiter's clouds is about -230 degrees F
        > (-145 degrees C), though at its core the mercury soars to 3,000
        > degrees F (24,000 degrees C).
        >
        > The brown dwarf, named CFBDS J005910.83-011401.3, is about 40
        > light-years from our solar system. It was found by an international
        > team using the Canada France Hawaii Telescope and Gemini North
        > Telescope, both located in Hawaii, and the a European Southern
        > Observatory telescope in Chile.

        ...
      Your message has been successfully submitted and would be delivered to recipients shortly.