Slashdot Mirror

← Back to Stories (view on slashdot.org)

Giant Planet Nine Times the Mass of Jupiter Found

Posted by Soulskill on from the fat-planets dept.

cremeglace writes "In the late 1990s, astronomers noticed a distinct warp in the disk of dust and gas orbiting a young star some 60 light-years from Earth. Now, using new analytical tools, researchers have discovered a giant planet lurking within the dusty haze. About nine times as massive as Jupiter and composed mainly of gas, the planet is only a few million years old, proving that such enormous planetary bodies can form rapidly." What's amazing about this is that the images taken of the star clearly show the planet first on one side of the star, and then the other, several years later.

8 of 73 comments (clear)

  1. Amazing by x_IamSpartacus_x · · Score: 2, Informative

    Ok, IANAA (*not an astronomer) but what's amazing about the planet on one side of the star and then the other several years later? Don't most planets orbit stars at varying rates ("years" to us earthlings)? I'm confused by the fact that it's amazing for a large planet to be orbiting its star.

    1. Re:Amazing by Chris+Burke · · Score: 3, Informative

      They were suggesting that it's amazing that our images clearly show it.

      Not that it happens.

      --

      The enemies of Democracy are
  2. Mass isn't the story by The+Bad+Astronomer · · Score: 5, Informative

    FWIW, mass isn't the story here; we know of hundreds of planets in that mass range. I would say the story is that two images taken a few years apart show the planet's motion, and that Beta Pic, the parent star, was the first to have a disk seen around it back in the 1980s. This planet explains the warp and other features in the disk, too, that have been known for years! I wrote about this on my Bad Astronomy blog.

    --
    *** Phil Plait, aka The Bad Astronomer http://www.badastronomy.com
    1. Re:Mass isn't the story by Chris+Burke · · Score: 3, Informative

      You need about 75 Jupiter masses to get sustainable stellar fusion, ignoring questions of composition.

      --

      The enemies of Democracy are
    2. Re:Mass isn't the story by Anonymous Coward · · Score: 1, Informative

      Gravity makes things denser if you just add mass. If you want stuff to be less dense, you have to heat them up, probably by starting fusion in the core. Just adding more mass to Jupiter won't change the volume significantly, it just gets compressed .If you start fusing Helium instead of Hydrogen in the core, temperatures there rise dramatically, allowing the outer, non-fusing parts of the object to expand.

  3. Re:Not a star now? by Trepidity · · Score: 2, Informative

    The cutoff seems to be somewhat higher, at around 13 times the mass of Jupiter.

    --
    10 PRINT CHR$(205.5+RND(1)); : GOTO 10
  4. Re:Not a star now? by MozeeToby · · Score: 4, Informative

    So to summarize:

    If it shines it's a star.
    Else if the mass is greater than the theoretical minimum for fusion (13 Jupiter masses), it is a brown dwarf.
    Else if the mass orbits a star or stellar remnant it is a planet
    Else it is a 'sub-brown dwarf'

  5. Re:It's a trap! by stonefry · · Score: 3, Informative

    Great, they rebuilt the Death Star a second time and now we found it.

    Come on, that was a long time ago. And really far away.