New Class of Galaxy Discovered 104
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.'"
Re:Less massive but prolific star creators (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.
Re:Just random chance we see no recent ones? (Score:3, Informative)
It's not quite so straightforward due to the complexities of how the peas are actually selected, I think. http://arxiv.org/pdf/0907.4155v1 is the paper - section 2 and 5 might be of interest with respect to this sort of question.
Re:Time to be pendantic! (Score:5, 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.
Re:Why a new class? (Score:3, Informative)
HST images were needed to investigate the morphology - the shapes just couldn't be picked out in the original images as the galaxies are so compact. However, it looks like a number of them have complex shapes hinting that they are or have recently been involved in mergers with other galaxies. We don't have much to go on at the moment though.
Re:Why a new class? (Score:3, Informative)
Basically young stars have a different kind of emission to old stars. You can essentially count up the amount of light from young stars and work out how much star formation you need to have that population.
Re:Why a new class? (Score:4, Informative)
Peas were user discovery (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.
Re:Peas were user discovery (Score:2, Informative)
Re:Time to be pendantic! (Score:4, 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.
Re:Less massive but prolific star creators (Score:3, Informative)
The OP's insane speculation reminds me of the Electric Universe [wikipedia.org] crazies. Every field has its lunatic fringe.
Re:no center and no beginning (Score:3, Informative)
There may have been a time when we didn't have tools for explaining the universe besides appeals to personal aesthetics, but today we've got things like formulating hypothesis that explain past observations and lead to empirically falsifiable predictions of future observations, and then constructing experimenets to attempt to falsify those predictions.
Odd things these peas (Score:3, Informative)
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