The earliest stars in the Universe
A faint star in the southern Milky Way has been found to consist virtually only of hydrogen and helium, with only 1/200,000 of the heavier elements seen in the sun. Credit: ESO VLT
(PhysOrg.com) -- Matter in the universe after the big bang consisted almost entirely of hydrogen and helium atoms. Only later, after undergoing fusion reactions in the nuclear furnaces of stars, did these light elements transform into all the other (so-called "heavy") elements that are found in the cosmos today. But astronomers know that the process of making stars, at least today, includes important roles for these heavy elements, for example helping the pre-stellar cloud collapse until the first nuclear reactions can ignite. How, then, did the first stars form, and what did subsequent generations of stars look like?
According to the current theory, the first generation of stars had to be very massive, about one hundred times the mass of our sun, in order to trigger the first nuclear fusion reactions. When these stars died as supernovae, they seeded the surrounding gas with chemically enriched material that enabled the birth of a first generation of lower mass and longer lived-stars. Today some of these stars are still shining. Astronomers observe them as stars comparatively deficient in heavy elements, since unlike stars born recently, they had only one (or a few) generations of supernovae to enrich their natal clouds. By studying these surviving low-mass, heavy-element deficient stars, scientists are able to test theories and measure the conditions in the early universe.
CfA astronomer Anna Frebel and seven colleagues have completed a comprehensive study of twenty key elements in sixteen heavy-element deficient stars in the outer regions of the Milky Way, some of them with almost ten thousand times fewer heavy atoms (compared to hydrogen) than in the sun. They found good agreement with theory, but discovered that apparently there are several chemically distinct kinds of such deficient stars, for example depending on the amounts of iron, lithium, or other species. Their results not only help to confirm the models, but serve as a test of new software tools that will facilitate a more efficient search for aged remnants of the earliest stars of the universe.
Provided by
Harvard-Smithsonian Center for Astrophysics
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Dec 19, 2011
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The first question that arises is how did this accumulation of gas occur in order to form such a big mass? Remember that according to the bb theory everything was flying apart at horrendous speeds PLUS inflation had smoothed out any irregularities, so what exactly happened physically that resulted in a sudden braking and conglomeration of particles?
The current weak answer is density fluctuations [ unless that little item has been updated recently, but I'm not aware of any such ] but where would those come from for the first stars - and just how would those result in ANY accumulation of mass to the extend of 100 times the mass of the sun?
The second question is - where are the supernova remnants? There are no recorded type III remnants to correspond to such early stars-unless I'm ill advised.
Dec 19, 2011
Rank: 1.4 / 5 (10)
Maybe I'm missing something here - if one has super massive stars [ as required to form the first ones ], don't they burn out quickly as blue stars and die an early death? So how come some are still hanging around? Maybe I need a refresher in the new astronomy.
Dec 19, 2011
Rank: 1 / 5 (7)
Observations and measurements suggest however that the universe is infinite and cyclic, powered primarily by competition between neutron repulsion and gravitational attraction, always dynamic and alive - just like you and me.
Here's the rest of the story that politicians tried to suppress so they could pretend control over the much more powerful forces of nature.
http://dl.dropbox...asks.pdf
www.omatumr.com/Overheads/Overheads.htm]www.omatumr.com/O...eads.htm[/url]
www.foxnews.com/s...er-fire/
www.ipa.org.au/pu...c-alarms
With kind regards,
Oliver K. Manuel
www.omatumr.com
http://myprofile....anuelo09
Dec 19, 2011
Rank: 1 / 5 (6)
http://www.omatum...eads.htm
Dec 19, 2011
Rank: 5 / 5 (6)
Yes, that is still the basic paradigm for "primordial star formation" (search for those words).
The fluctuations observed in the "cosmic microwave background" mean that there are (slight) concentrations of matter that allow for gravitational contraction of the higher density regions. As they contract the gas motions create new fluctuations that seed the collapse of smaller regions. This "cascade" proceeds until other forces (like gas pressure) become strong enough to halt fragmentation. For primordial gas that is at the scale where massive stars form.
Dec 19, 2011
Rank: 5 / 5 (6)
SN remnants (SNR) are fairly short-lived objects (10s to 100s of thousands of years) and relatively faint. They are too faint to see in the distant universe where the SNR from the first SNe might still exists and too old to remain in the local region where we can see SNRs. We haven't (yet) seen the SNe from the first stars, so it is reasonable that we haven't seen any related SNRs either.
The gas in the SNR is mixing with the surrounding interstellar medium (ISM) and when that mixes with pristine gas and the ejecta of other SNe, it can trigger the formation of the next generation(s) of stars.
Dec 19, 2011
Rank: 5 / 5 (4)
Your doing OK, Kevin. The title would be better "oldest stars in the Galaxy" for this article.
This is one case where astronomers are unusually "mathematical" in their definitions.
"First", "Primordial" or "Population III" stars are made from just BB gas with NO (none at all) enrichment from previous stars. We currently expect these stars to be massive.
The stars ("very", "extremely", etc., metal-poor) studied here are the lower mass stars formed from the debris of these explosions (and perhaps a few more generations of massive stars, that is uncertain) and survive from very early in the development of our Galaxy.
Dec 19, 2011
Rank: 5 / 5 (1)
Nope. A refresher in basic literacy. Reread the article. They are talking about low mass stars produced a few generations after the first ones went Supernova.
Dec 19, 2011
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Dec 19, 2011
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IN addition most of these occurred in the dark ages and cannot ever be seen.
Dec 19, 2011
Rank: 5 / 5 (2)
The first question that arises is how did this accumulation of gas occur in order to form a god? Remember that according to the bible theory everything was created at horrendous speed (7 days) PLUS the bible had smoothed out any logical irregularities, so what exactly happened physically that resulted in a sudden braking and conglomeration of god?
The current weak answer is the dense Discovery Institute [ unless that little item has been updated recently, but I'm not aware of any such ] but where would those idiotic ideas come from in the first place - and just how would they result in ANY accumulation of scientific knowledge at all?
The second question is - where are the bible creation remnants? There are no recorded type III remnants to correspond to such a late creation (6 kya)- unless I'm ill advised and uber ignorant.
Dec 20, 2011
Rank: 1 / 5 (4)
Of course there is no indication in the Bible that those 7 days were in fact our Earth days. Could very well be that a day for God is 2.3 billion years ± 0.02. So.. He is still resting now - and will for another 2.3 ± 0.02 minus 0.0000057 billion years - and just dabbles around a little.
Dec 20, 2011
Rank: 1 / 5 (2)
Of course there is no indication in the Bible that those 7 days were in fact our Earth days. Could very well be that a day for God is 2.3 billion years ± 0.02. So.. He is still resting now - and will for another 2.3 ± 0.02 minus 0.0000057 billion years - and just dabbles around a little.
Dec 20, 2011
Rank: 5 / 5 (1)
@ Stellar-demolitionist some good responces there but you should know that Kevin is a known creationist and these mistakes you pointed out are deliberate. Intended for troling purposses.
@mahal kita very good explanation. Of course it is just an tactic Religionists use to address the factuall errors in a Bible story by trying to alter a bible myth to fit in with scientific theory or fact. Just like how Christianity converted the pagans by making it seem the same ( and easier to accept ) as the pagans beliefs.
Dec 21, 2011
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so earth is suddenly right around 13 billion years old?
"Let the earth put forth vegetation, plants yielding seed, and fruit trees bearing fruit in which is their seed, each according to its kind, upon the earth." And it was so."
And there was evening and there was morning, a third day."
so life came fully evolved and in its current form around 10 billion years ago?
"And God made the two great lights, the greater light to rule the day, and the lesser light to rule the night; he made the stars also."
So all the stars we see are around 8 billion years old and were created at the same time?
I could go on....