Strange Posted August 19, 2015 Posted August 19, 2015 Is this the sort of thing you are looking for: http://www.nature.com/nature/journal/v425/n6960/abs/nature02071.html So it seems that the creation of heavier elements (particularly carbon and oxygen) by the first stars may be what enabled the smaller stars we see today to form. Well, I thought this was interesting, even if Ant didn't. His questions had me wondering if the first generation of stars were large and short lived just because of the greater density of gas then, or if there were some other reason. It is interesting to see that even minute amounts of other elements can influence the creation and (presumably) evolution of stars.
dimreepr Posted August 19, 2015 Posted August 19, 2015 Sometimes even the simplest why can trigger a greater understanding.
swansont Posted August 19, 2015 Posted August 19, 2015 Why did You not just watch from the sidelines Dim and learn instead of jumping in with Your limited knowledge on this subject? ! Moderator Note Knock it off. Suggesting non-participation is inappropriate, especially when said participation is within the rules. Being wrong is not against the rules. Good thing, too, because everyone is wrong at some point. BTW, "knock it off" applies to everyone not engaging in the science being discussed here. 1
Ant Sinclair Posted August 19, 2015 Author Posted August 19, 2015 Well, I thought this was interesting, even if Ant didn't. His questions had me wondering if the first generation of stars were large and short lived just because of the greater density of gas then, or if there were some other reason. It is interesting to see that even minute amounts of other elements can influence the creation and (presumably) evolution of stars. I did look at this paper strange and the first thing I spotted was its' date; 2003, since then we've had the Planck Obsevatory/COBE datas to analyse aswell as others. The paper bears no relevance to this thread. Below is an excerpt and the link below to the article from which it came. Am I correct in thinking Deuterium plays an important role in the Fusion process? Deuterium can be obtained from this depth of more than 7 kilometers below sea level under 10,000 psi of ocean pressure, replenished by nature 24 hours a day from the Central America across the vast Pacific Ocean. The amazing thing about deuterium is that at room temperatures or normal atmospheric pressure, deuterium atoms are electrolyzed naturally out of water dispelling hydrogen gas. http://deuteriumproject.blogspot.co.uk/2011/04/deuterium-project-twenty-years-ago.html?m=1 Can I please ask again of the science forums experts on how gases behave in the voids of space, do they behave similarly to the partial pressures We observe on Earth or do they behave totally differently?
Klaynos Posted August 19, 2015 Posted August 19, 2015 Did you consider search who has cited the paper of you fear it's too old (which it probably isn't)?
Ant Sinclair Posted August 19, 2015 Author Posted August 19, 2015 Did you consider search who has cited the paper of you fear it's too old (which it probably isn't)? I don't fully comprehend this statement Klaynos but while You are here could You answer how gases differ in behaviour with respect to the Earth and Deep Space?
Strange Posted August 19, 2015 Posted August 19, 2015 I did look at this paper strange and the first thing I spotted was its' date; 2003, since then we've had the Planck Obsevatory/COBE datas to analyse aswell as others. That has nothing to do with water or star formation, which I thought was the subject of the thread. The paper bears no relevance to this thread. The paper is about the role of oxygen (one of the components of water) in the formation of stars, which I thought was the topic of the thread. Below is an excerpt and the link below to the article from which it came. Am I correct in thinking Deuterium plays an important role in the Fusion process? Yes it does (and it was created in the big bang). Deuterium can be obtained from this depth of more than 7 kilometers below sea level under 10,000 psi of ocean pressure, replenished by nature 24 hours a day from the Central America across the vast Pacific Ocean. The amazing thing about deuterium is that at room temperatures or normal atmospheric pressure, deuterium atoms are electrolyzed naturally out of water dispelling hydrogen gas. Now that really is nothing to do with the thread! Can I please ask again of the science forums experts on how gases behave in the voids of space, do they behave similarly to the partial pressures We observe on Earth or do they behave totally differently? They will be at much lower pressures. They will often be ionized. But apart from that, I'm not sure why they would behave significantly differently. What sort of behaviour are you thinking of? (The paper you said isn't relevant is all about the behaviour of gas clouds...)
Ant Sinclair Posted August 19, 2015 Author Posted August 19, 2015 No strange, what Iam suggesting is that water was formed along with H, He, Li & Be. If gases behave similarly in space as they do on Earth (partial pressure effect) then I don't subscribe to "gases falling in on themselves due to gravity to give birth to stars"! What I do believe is that water was formed at the same time along with the elements mentioned earlier, and water would amass in huge quantities, then these huge collections of water would collect tritium and deuterium into their centres, as more H2O was attracted a critical pressure at the centre of these would be reached and then BANG!
Strange Posted August 19, 2015 Posted August 19, 2015 No strange, what Iam suggesting is that water was formed along with H, He, Li & Be. And the evidence for that is? If gases behave similarly in space as they do on Earth (partial pressure effect) then I don't subscribe to "gases falling in on themselves due to gravity to give birth to stars"! Why not? Gasses on Earth are attracted and compressed by gravity. Why wouldn't the same happen in space? What I do believe is that water was formed at the same time along with the elements mentioned earlier, and water would amass in huge quantities, then these huge collections of water would collect tritium and deuterium into their centres, as more H2O was attracted a critical pressure at the centre of these would be reached and then BANG! Beliefs with no evidence are not of much value. You had better ask the moderators to move this to the Speculations forum...
Ant Sinclair Posted August 19, 2015 Author Posted August 19, 2015 Why not? Gasses on Earth are attracted and compressed by gravity. Why wouldn't the same happen in space? mmmmm .... and conditions in space(pre-star) are just like they are when they are surrounding a huge rock - please take the time to think about what You are writing strange!!!! -3
Strange Posted August 19, 2015 Posted August 19, 2015 Why not? Gasses on Earth are attracted and compressed by gravity. Why wouldn't the same happen in space? mmmmm .... and conditions in space(pre-star) are just like they are when they are surrounding a huge rock - please take the time to think about what You are writing strange!!!! You think gas in space is not affected by gravity? https://en.wikipedia.org/wiki/Jeans_instability
Ant Sinclair Posted August 19, 2015 Author Posted August 19, 2015 Strange I'll come back to Your posts later, Please could one of the Resident Experts kindly explain on thread how gases behave in deep space - do they act similarly to how they do on Earth and Repel each other to spread evenly. And with this taking place in deep space are they likely to keep spreading out(pre-star)?
Strange Posted August 19, 2015 Posted August 19, 2015 (edited) Strange I'll come back to Your posts later, Please could one of the Resident Experts kindly explain on thread how gases behave in deep space - do they act similarly to how they do on Earth and Repel each other to spread evenly. And with this taking place in deep space are they likely to keep spreading out(pre-star)? Gases do not, as far as I know, repel one another. The atoms or molecules in a gas are a certain distance apart because of their constant movement. In the absence of something constraining them (a container or gravity, for example) they will therefore tend to diffuse to fill the available volume. In the case of gasses in space, there is gravity preventing them dispersing completely. And possibly causing their eventual collapse. They may also be ionized, which means there would be electric and magnetic fields affecting their behaviour as well. How do gases behave in deep space? You could start here: https://en.wikipedia.org/wiki/Jeans_instability What does any of this have to do with water, though? Edited August 19, 2015 by Strange
Acme Posted August 19, 2015 Posted August 19, 2015 Whether a hydrogen cloud collapses or not depends on its mass, radius, and temperature. Not all hydrogen clouds condense to form stars, but some do. Stellar Evolution ... 2a. Jeans Radius for cloud collapse. A cloud with radius R, mass M, and temperature T will collapse to form a star if the total energy of the cloud is <0, i.e, if the (absolute value) of the potential energy exceeds the thermal energy of the cloud: where N is total number of particles in cloud ...
ACG52 Posted August 19, 2015 Posted August 19, 2015 No strange, what Iam suggesting is that water was formed along with H, He, Li & Be. When those elements formed there was no oxygen, so water could not form along with them. Stellar nucleosythesis, the mechanism which produced all elements above Be is a well studied and well understood process. https://en.wikipedia.org/wiki/Stellar_nucleosynthesis at the time the first generation of stars formed, there was no oxygen, hence no water.
swansont Posted August 19, 2015 Posted August 19, 2015 No strange, what Iam suggesting is that water was formed along with H, He, Li & Be. Compare the temperature of the universe with the temperature required to disassociate water. For 1 eV, kT is about 11,600K. That could not have happened for (tens of) thousands of years, even if oxygen has been made, which it wasn't.
Mordred Posted August 19, 2015 Posted August 19, 2015 (edited) Are you aware water dissociates at high temperature, roughly 2200 degrees Celsius? In order for water to be stable the universe must be cooler than that value. Star fusion has a far far higher core temperature. For example our Sun has a core temperature of roughly 14 million Kelvin. Water cannot stay stable at those temperatures. Water is such an important substance to Our Type of life-forms here on Earth, but exactly how long has the Old H2O been around? Was it 'created' pre or post star? If it was created pre-star, what involvement could it have had in the creation of stars if any? So water cannot be created in stars, and can only form with stability when the universe cools sufficient enough to allow stability. To make matters worse electromagnetic currents also dissociate water.http://www.eolss.net/sample-chapters/c08/e3-13-03-01.pdf Edited August 19, 2015 by Mordred
sunshaker Posted August 19, 2015 Posted August 19, 2015 Water is such an important substance to Our Type of life-forms here on Earth, but exactly how long has the Old H2O been around? Was it 'created' pre or post star? If it was created pre-star, what involvement could it have had in the creation of stars if any? How soon after the Big Bang could water have existed? Not right away, because water molecules contain oxygen and oxygen had to be formed in the first stars. Then that oxygen had to disperse and unite with hydrogen in significant amounts. New theoretical workfinds that despite these complications, water vapour could have been just as abundant in pockets of space a billion years after the Big Bang as it is today. This research is interesting as it seems our universe, even in its first billion years, nurtured a rich environment for H2O production in clouds that were comparatively oxygen poor. This then set the stage for later epochs when later stars began forming planets where water was already present. And now we live in a universe apparently filled with water that just happens to be the key component for life as we know it. http://news.discovery.com/space/astronomy/when-did-the-universe-flood-with-water-150428.htm Water water everywhere and not a drop to drink.
Strange Posted August 19, 2015 Posted August 19, 2015 (edited) When those elements formed there was no oxygen, so water could not form along with them. Stellar nucleosythesis, the mechanism which produced all elements above Be is a well studied and well understood process. Interestingly, the early work on stellar nucleosynthesis was carried out by Fred Hoyle, a strong opponent (and namer) of the big bang theory. Ironic that it is this that proved to be one of the strongest pieces of evidence for the big bang. Was it 'created' pre or post star? Can we clarify what you mean by this. By "pre star" do you mean (a) before all stars or (b) before some particular star (e.g. the Sun)? If (a) then the answer is clearly no. if (b) then the answer is yes for second generation (and later) stars. Edited August 19, 2015 by Strange
Ant Sinclair Posted August 19, 2015 Author Posted August 19, 2015 Are you aware water dissociates at high temperature, roughly 2200 degrees Celsius? In order for water to be stable the universe must be cooler than that value. Star fusion has a far far higher core temperature. For example our Sun has a core temperature of roughly 14 million Kelvin. Water cannot stay stable at those temperatures. So water cannot be created in stars, and can only form with stability when the universe cools sufficient enough to allow stability. To make matters worse electromagnetic currents also dissociate water. http://www.eolss.net/sample-chapters/c08/e3-13-03-01.pdf Mordred You'll know of megamasers, in particular the H2O & OH megamasers, are these not present at the beginning of star formation? Below is a paper, firstly an extract from it and then the link to it. Masers occur astrophysically and are typically associated with star formation. arXiv:1504.07194v2 [astro-ph.GA] 28 Apr 2015 -2
Strange Posted August 19, 2015 Posted August 19, 2015 Mordred You'll know of megamasers, in particular the H2O & OH megamasers, are these not present at the beginning of star formation? Below is a paper, firstly an extract from it and then the link to it. Masers occur astrophysically and are typically associated with star formation. arXiv:1504.07194v2 [astro-ph.GA] 28 Apr 2015 These can be associated with areas of high star formation. They have little or nothing to do with the creation of stars. As you haven't provided a link (or an extract) here it is: http://arxiv.org/abs/1504.07194 Have you read this paper? You now appear to be randomly searching for anything with the word "star" and "water" and throwing it at the forum. It would be more productive if you actually, you know, discussed the comments other have made and answered some questions.
Ant Sinclair Posted August 19, 2015 Author Posted August 19, 2015 These can be associated with areas of high star formation. They have little or nothing to do with the creation of stars. As you haven't provided a link (or an extract) here it is: http://arxiv.org/abs/1504.07194 Have you read this paper? You now appear to be randomly searching for anything with the word "star" and "water" and throwing it at the forum. It would be more productive if you actually, you know, discussed the comments other have made and answered some questions. THE HYDROXYL-WATER MEGAMASER CONNECTION. I. WATER EMISSION TOWARD OH MEGAMASER HOSTS Brandon K. Wiggins and Victor Migenes, Brigham Young University, Provo, UT 84604 and Joseph M. Smidt Los Alamos National Laboratory, Los Alamos, NM, 87544 Draft version April 29, 2015 Are these not respected establishments or people then strange? -1
Strange Posted August 19, 2015 Posted August 19, 2015 Are these not respected establishments or people then strange? I'm sure they are. Who suggested they are not? Why can't you explain why you posted a reference to this article? Why didn't you provide a link?Why do you always answer a question with more questions? Why do you refuse to discuss the subject? But what is your point, here? We know there is water (and hydroxyl ions) in interstellar gas clouds. We know that, under the right circumstances, these can be stimulated to form masers. How is this connected to the subject of this thread? Was it 'created' pre or post star? Can we clarify what you mean by this. By "pre star" do you mean (a) before all stars or (b) before some particular star (e.g. the Sun)? If (a) then the answer is clearly no. if (b) then the answer is yes for second generation (and later) stars. What part of your original question has not been answered? Why not?
Ant Sinclair Posted August 19, 2015 Author Posted August 19, 2015 http://news.discovery.com/space/astronomy/when-did-the-universe-flood-with-water-150428.htm Water water everywhere and not a drop to drink. Thanks for Your post Sun, with reference to the last link in Your post please see below; Reionization, 150 million to 1 billion years: The first quasars form from gravitational collapse, and the intense radiation they emit reionizes the surrounding universe, the second of two major phase changes of hydrogen gas. I believe it was H2O being formed that was this second phase of H!
Strange Posted August 19, 2015 Posted August 19, 2015 I believe it was H2O being formed that was this second phase of H! H2O is not a phase of hydrogen (the clue is in the "O"). 1
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