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New Galactic Neighbor

Posted by samzenpus on from the there-goes-the-neighborhood dept.

Dan Yocum writes "The Sloan Digital Sky Survey reveals a new Milky Way neighbor: a galaxy so big we couldn't see it before. A huge but very faint structure, containing hundreds of thousands of stars spread over an area nearly 5,000 times the size of a full moon, has been discovered and mapped by astronomers of the Sloan Digital Sky Survey."

12 of 200 comments (clear)

  1. Spece is big by Anonymous Coward · · Score: 0, Interesting


    Real Big

  2. How do they define a galaxy? by keraneuology · · Score: 2, Interesting

    What makes this a galaxy rather than just some random swirl in the cosmos? (TFA doesn't really say)... does this galaxy have a black hole to call its own in the middle? What happens if a black hole eats another black hole?

    --
    If the g'vt kept the data on you that google does you'd better believe you'd be calling it "doing evil"
    1. Re:How do they define a galaxy? by waytoomuchcoffee · · Score: 4, Interesting

      Black hole collisions are theoretically possible, and has been simulated on a Cray

      Yes, this is offtopic, but what is really wild is that they simulated that in 1994 on a Cray C90, which has a floating point speed of 16 gigaflops. Back here in 2006: the Playstation 3, a TOY, has a floating point speed of 2 teraflops.

    2. Re:How do they define a galaxy? by (negative+video) · · Score: 2, Interesting
      The jury is out on the existance of supermassive holes at all galactic centers (partly due to obvious impossibility of direct detection).
      I disagree. The orbits of stars that get very close (while moving very fast!) to our galaxy's central mass have been directly observed, as shown on this page, which includes an amazing movie of stars whipping around the central mass. Likewise, we have observed strong x-ray variability of that region on a time scale of hours, implying a source no larger in size a few light-hours. That pretty much proves it's a black hole.

      Above the only stronger evidence would be to watch it eclipse a star. Unfortunately the necessary arrangement of star, black hole, and US are unlikely to occur.

    3. Re:How do they define a galaxy? by Crayon+Kid · · Score: 2, Interesting

      Stephen Hawking mentioned something like 95% chance of a black hole being located at the center of our galaxy, in his book "A brief history of time". In spite of all the circumstancial evidence, absolute proof aka 100% certainty is something different.

      --
      i ate crayons when i was a kid and now i have two braincells and the blue ones taste nicer
    4. Re:How do they define a galaxy? by keraneuology · · Score: 2, Interesting

      I've always wondered why people tend to think of a black hole as funnel-shaped: aren't they always spherical? If the singularity is at 0,0,0 and the hole looks like some cosmic tornado then this would imply that the event horizon (assuming a vortex that is straight up and down) would involve pi*d focused around 0,0,10 or something. A copy of Gigli located just below the singularity would be sucked in just as quickly as something just to the right or the left, meaning that the gravitational field extends more or less uniformly along all three axiseseses. So from whence comes the funnel shape?

      --
      If the g'vt kept the data on you that google does you'd better believe you'd be calling it "doing evil"
  3. Could this be... by idonthack · · Score: 5, Interesting

    Could this be what's warping the Milky Way, previously thought to be Dark Matter?

    --
    Why is it that when you believe something it's an opinion, but when I believe something it's a manifesto?
  4. Star Question by dkdeath1 · · Score: 2, Interesting

    I am not well versed in astronomy in general, but how could it be so faint we havent noticed it yet? Isint there a certain level of luminosity that is required to be a star? Could there possible be something between us and this galaxy?

  5. Re:Wrong priorities... by JWSmythe · · Score: 4, Interesting

    "before they invade us,"

        Optimistic, aren't you?

        Even worse, if you consider that we are the aliens, and our species has simply invaded and conquered this planet an aen ago. We adapted, survived, and destroyed our own history. If you don't understand the destroyed part of that, go to a library and read some 6,000 year old books. Assuming you knew the language, you wouldn't find the books. They're lost, damaged, and/or intentionally destroyed over the years.

        We are the aliens, and our brothern have forgotten about us. We will be stuck here, alone, for a long time.

    --
    Serious? Seriousness is well above my pay grade.
  6. Re:Wrong priorities... by 1u3hr · · Score: 2, Interesting
    if we are marooned aliens then did apes evolve from us?

    Yes, see Larry Niven's Protector.

  7. Re:Not very long ago... by Gryle · · Score: 2, Interesting

    That's no galaxy....

    --
    Only two things are infinite, the universe and human stupidity, and I'm not entirely sure about the universe - Einstein
  8. Re:Galaxy?! by SlowMovingTarget · · Score: 3, Interesting

    Actually, on an intergalactic scale, this thing is freakishly close. According to TFA this dwarf galaxy is 30,000 light years from Earth. The distance from Earth to the center of the Milky Way galaxy is roughly 27,700 light years (according to Wikipedia). This thing is nearly right on top of us.

    BTW, if you're preparing to shoot it, the quote you're looking for is "It's coming right for us!"