I came across this in a post on Istapundit, titled "Archeology of Stars". I followed the link to a longish NYT piece by Curtis Brainard, and then I followed one of Brainard's links back to an abstract in Science. Author was an MIT astronomer, Dr. Anna Frebel. So I read the abstract, several times.
Lead sentence. "Current cosmological models1, 2 indicate that the Milky Way’s stellar halo was assembled from many smaller systems." Hmm. Tell me about those "systems". Systems of what? Stars, dark matter, gas and dust, Legos, black holes, auto parts? Surely Dr. Frebel could have used a more specific phrase in the lead sentence. The use of the verb "assembled" is off putting. We assemble manufactured goods like cars, Ipads, TV sets. Surely she doesn't mean the Milky Way galaxy was assembled in a galaxy factory.
Her next sentence contains the phrase "galactic building blocks". Maybe she was talking about systems of Legos? Then she introduces the phrase "dwarf galaxies" but does not define it. From context I think what she calls "dwarf galaxies" are what used to be called "globular star clusters".
Buried in the middle of the abstract we finally get down to the interesting stuff. She has discovered an extremely iron poor star in the "Sculptor dwarf galaxy". Not being an astronomer, I don't know where the Sculptor dwarf galaxy is, but I guess it is a globular cluster attached to our Milky Way. In short, something close by, or at least close compared to the quasars which are so distant as to be nearly as old as the Big Bang.
Why is iron-poor interesting. Iron poor makes the star old, perhaps as old as the quasars. The Big Bang is thought to have filled the universe with only hydrogen and helium. The first stars lacked any heavy elements, and in fact created all the heavy elements by fusion. Therefore an iron poor star is old because it formed before the heavy elements were made. And, this one is close enough to get a good look at. The quasars are so far away that little can be learned about them.
Dr. Frebel has made a very interesting discovery. But her English language skills are so poor that she would have flunked high school English at my school. Someone should give her a copy of Strunk and White. She would become a more widely known astronomer if she would bother to learn how to write decent English.
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