Posted on 11/15/2009 6:15:09 PM PST by SunkenCiv
Sunlike stars that harbor planets are low on lithium, according to a recent study that may offer a new tool in the hunt for planets beyond our solar system. Stars are made almost entirely of hydrogen and helium. A small percentage of a star's mass comes from heavier elements, which astronomers refer to as metals. Young, yellow stars like our sun usually have more metals than older, redder stars, although the exact mix of those metals can vary. But astronomers have been unable to explain why otherwise similar sunlike stars have widely different lithium levels.The new study suggests that the answer lies with the presence of planets... It's been a puzzle for decades why our sun has significantly less lithium on its surface than other stars of the same age, mass, and metal abundance. For the new study, Israelian and colleagues monitored 451 sunlike stars, 70 of which were already known to harbor planets... Observations made over several years revealed that all the known planetary hosts had similarly low lithium levels. By contrast, stars that have been scrutinized for years, without any planets having been found, had almost ten times more lithium than stars with known planets. Why, exactly, planets would cause lithium depletion remains unknown.
(Excerpt) Read more at news.nationalgeographic.com ...
A disk of planet-forming material swirls around a young star in an artist's conception. Sunlike stars known to have planets have relatively little lithium on their surfaces, according to a November 2009 study that could offer a new tool in the hunt for planets beyond our solar system. [Picture courtesy ESO/L. Calcada]
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I prefer latinum.
Maybe the media used it all.
Mystery of the Missing Sunspots, Solved?(No, not Rove)
NASA | June 17, 2009 | Dr. Tony Phillips
Posted on 06/17/2009 4:57:29 PM PDT by decimon
http://www.freerepublic.com/focus/chat/2274015/posts
http://www.freerepublic.com/focus/f-chat/1294934/posts?page=49#49
Cecilia Payne-Gaposchkin: Astronomer And Astrophysicist
1900-1980
by Owen Gingerich
Harvard Smithsonian Center for Astrophysics
http://www.harvardsquarelibrary.org/unitarians/payne2.html
In a short chapter entitled “The Relative Abundance of the Elements” there is a ticking time bomb. This is the extremely high abundance of hydrogen and helium that had come out under certain assumptions in the analysis. Although we know today that this high abundance is real, at the time it produced an apparent anomaly with respect to the assumed homogeneity of the solar system. After all, when the earth is taken as a whole, it must be predominately iron in order to account for its high mean density, and this is supported by the fact that meteorites are largely iron and by the appearance of the solar spectrum itself, which shows more lines of iron than any other element. The very important principle of uniformity of nature seemed at stake. As Cecilia herself argued in her thesis, “If . . . the earth originated from the surface layers of the sun, the percentage composition of the whole earth should resemble the composition of the solar (and therefore of a typical stellar) atmosphere. . . . Considering the possibility of atomic segregation both in the earth and in the star, it appears likely that the earth’s crust is representative of the stellar atmosphere.”21 So in her final table of abundances, she omitted hydrogen and helium.
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Could be they’re dead wrong about solar system formation. :’)
Well, and that of the need for lithium on the part of the galactic “mother ship” building companies.
Is lithium a good investment now?
:’)
Well, Manic Depression IS a Frustratin’ Mess.
Rules of Acquisition #102: Nature decays but latinum lasts forever.
bingo...
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