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New Class of Galaxy Discovered

Posted by Soulskill on from the give-peas-a-chance dept.

fructose sends along this excerpt from Space Daily: "A team of astronomers has discovered a group of rare galaxies called the 'Green Peas' with the help of citizen scientists working through an online project called Galaxy Zoo. The finding could lend unique insights into how galaxies form stars in the early universe. ... Of the 1 million galaxies in Galaxy Zoo's image bank, only about 250 are in the new 'Green Pea' type. Galaxy Zoo is claiming this as a success of the 'citizen scientist' effort that they spearheaded. ... The galaxies, which are between 1.5 billion and 5 billion light years away, are 10 times smaller than our own Milky Way galaxy and 100 times less massive. But surprisingly, given their small size, they are forming stars 10 times faster than the Milky Way. 'They're growing at an incredible rate,' said Kevin Schawinski, a postdoctoral associate at Yale and one of Galaxy Zoo's founders. 'These galaxies would have been normal in the early universe, but we just don't see such active galaxies today. Understanding the Green Peas may tell us something about how stars were formed in the early universe and how galaxies evolve.'"

11 of 104 comments (clear)

  1. Re:so do they exist in their current form? by Ukab+the+Great · · Score: 5, Funny

    If you'd patiently wait 5 billion more years, you'd know the answer.

  2. Time to be pendantic! by kimvette · · Score: 5, Insightful

    "10 times smaller than our own Milky Way galaxy and 100 times less massive"

    10 times smaller?
    100 times less massive?

    Isn't it 1/10 the size and 1/100 the mass?

    In order to be "10 times smaller than $foo" or "100 times less massive than $foo" doesn't there need to be another point of reference?

    I know I'm picking nits, but this is slashdot. People should know better. This bugs me like less vs. fewer, there/their/they're, your/you're, and so forth. I understand it is simply a colloquialism arising from poor grammar among the masses, but in the case of a scientific article, poor writing makes it more difficult to take the writer seriously.

    --
    The Christian Right is Neither (Christian nor right). See: Matthew 23, Matthew 25, Ezekiel 16:48-50
    1. Re:Time to be pendantic! by Kjella · · Score: 3, Interesting

      10^1 times smaller = 10^-1 times bigger, never really managed to see the problem with it. It's perfectly unambigious since it makes no sense to refer to less than nothing. Things like there/their/they're that actually have three different meanings are much more annoying.

      --
      Live today, because you never know what tomorrow brings
    2. Re:Time to be pendantic! by nedlohs · · Score: 4, Informative

      It's standard English and has been for hundreds of years.

      Yes mathematically it makes no sense, but language isn't mathematics. And look you understood that it meant 1/10th and 1/100th so from a linguistically it expressed what was intended just fine, even to people who think in math instead of language.

      Unless you're arguing "smaller' needs a qualifier to indicate it means volume. Even that seems a stretch since there are only two options, volume and mass, and the mass is taken by the 100x part.

    3. Re:Time to be pendantic! by Chris+Burke · · Score: 3, Informative

      Draw it on a number line: 10 is ten times larger than 1 because it is ten times farther from 0 on a number line. 1 is ten times less than x because it is ten times farther from y on a number line. Go on, fill in the values for x and y.

      No, 10 is ten times larger than 1 because the ratio of their sizes is 10:1.

      1 is ten times smaller than 10 because the ratio of their sizes is 1:10.

      It's about relative not absolute size difference. That's why they say "10 times smaller" rather than "10 units smaller". "Times" is your clue that you're dealing with multiplication, i.e. ratios.

      The language is perfectly clear, correct, and unambiguous. No, your reading comprehension is not fine.

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    4. Re:Time to be pendantic! by Chris+Burke · · Score: 4, Insightful

      It's oxymoronic to say "times smaller".

      No it isn't, unless you think you can only multiply by values larger than one, which would simply be moronic.

      You're suggesting implied reciprocals means "one xth the size of" when the latter is perfectly fine English just to avoid explicitly mentioning a fraction.

      Yes, heaven forbid there be multiple correct and clear ways to say the same thing in English. *eyeroll* In some cases it flows better than using fractions.

      It makes as much sense as talking about the "near distant" future.

      No, it makes perfect sense as long as you understand what it means. Which isn't complicated, and now you know it, so there should be no further issues with this perfectly clear and unambiguous language.

      --

      The enemies of Democracy are
  3. Oh, another expansion pack by The_mad_linguist · · Score: 5, Funny

    Great, another overpriced expansion pack. I guess sales from the last time they added a class have dropped, so astronomers are making new areas and classes rather than trying to balance the existing content.

    NERF ANDROMEDA!

  4. Just random chance we see no recent ones? by grimJester · · Score: 4, Interesting

    Since there are 250 of them between 1.5 billion and 5 billion light years away, you have roughly 2 per billion light year sphere. If we could expect to see an average of two within a billion light years from us, meaning within a billion years back, perhaps they still exist and we just don't happen to have any nearby?

    Given their density within the 5 billion light year sphere, it should be possible to calculate the odds of having 1.5 billion light years to the closest one.

  5. Re:Less massive but prolific star creators by HasselhoffThePaladin · · Score: 3, Informative

    Given that it is the expansion of the galaxy that causes the creation of matter, it makes sense that smaller, more active galaxies would be able to create new stars.

    I don't know how to respond to this statement. This is the tenth time I've written something before erasing it to start over to sound less inflammatory. I guess I'd just like a citation to this "theory" of the diffusion of matter begetting more matter. It sounds like some whacked-out solid state universe theory.

  6. Re:Why a new class? by wanerious · · Score: 3, Informative

    If you look at a population of stars and see lots of blue or UV light, it must be coming from very hot, massive stars. We also know that these stars don't live very long, so they must have formed recently --- this area must then be a region of star formation. The degree to which the overall spectrum is skewed towards the blue gives a rough indication of the star formation rate.

  7. Peas were user discovery by cayle+clark · · Score: 5, Informative

    I've spent a lot of hours classifying galaxies at GalaxyZoo. The abstract sense of making a tiny contribution to research gets thin real fast. What keeps me coming back is the surprise factor. You'll click away sorting boring balls and streaks and then up pops a perfect barred-spiral, or a swooshy collision or an oddity that doesn't fit any of the categories, and wakes you up. There are millions of galaxies in the deep-field surveys that are the source, most of them never looked at individually, and you never know what the software will toss up next.

    The site has an active and supportive forum community, and it was in the forums that the users -- not the astronomy post-docs who run the site -- first commented on the little green balls, suggested they might represent a unique class, and started collecting them as posts on a thread. There are user-run threads going on for other odd types of galaxy some of which might ultimately turn into research topics as well.