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A comment on Rosetta finds comet's water vapour to be significantly different from Earth's. Parent comment

Re:Rosetta finds comet's water vapour to be significantly di... by tomr_stargazer on Wednesday December 10, 2014 @05:13PM (#8732054)
>>> Why wouldn't water be one of the by products of the big-bang

To address the first part of your question – The Big Bang (which happened 13.8 billion years ago) created ~only hydrogen and helium. So, no water existed in the early Universe (a) because there were no oxygen atoms formed in the Big Bang and (b) the early Universe was too hot to form water molecules even if oxygen was present.

>>> during Earth's creation?

Whether water was present on the Earth from "day one" of its formation (~5 billion years ago, much later than the Big Bang) is still an open question, but part of why it might be unlikely is that the Earth is close enough to the Sun that it was too hot for water to stay as ice or liquid on Earth's surface (before Earth's atmosphere formed). Water that forms in comets (further away from the Sun) doesn't have that problem, as comets would be in colder parts of the early Solar System.

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Re:Rosetta finds comet's water vapour to be significantly di... by flavien_bessede on Wednesday December 10, 2014 @07:28PM (#8732551)
So what happened between the Big Bang and Earth formation? For some reason I always thought they were one and the same.
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Re:Rosetta finds comet's water vapour to be significantly di... by quantumet on Wednesday December 10, 2014 @07:33PM (#8732570)
Quite a lot; see for example:

http://en.wikipedia.org/wiki/Graphical_timeline_of_the_unive...

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Re:Rosetta finds comet's water vapour to be significantly di... by coldpie on Thursday December 11, 2014 @09:01AM (#8734706)
The Big Bang was the formation of the entire universe. About ten billion years later, our solar system, and eventually the Earth, started forming due to gravity pulling various bits of matter together. Ten billion years is a really, really long time! The two events are completely separate.

If you're interested in cosmology, there are a ton of fascinating popular science books on the topic, and research is very active and ongoing. As an introduction, I recommend Cosmos by Carl Sagan. It's a bit outdated these days, but the main points hold and it's a fascinating read from start to finish. Alternatively, if you prefer video, check out Cosmos: A Spacetime Odyssey with Neil deGrasse Tyson. It's an up-to-date retelling of Sagan's original idea.

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Re:Rosetta finds comet's water vapour to be significantly di... by MartinCron on Wednesday December 10, 2014 @11:05PM (#8733137)
Come on downvoters, it's a naive question, but not the sort of thing that needs to be punished...
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Re:Rosetta finds comet's water vapour to be significantly di... by lmm on Thursday December 11, 2014 @10:15AM (#8735139)
Two generations of stars, including heavy stars that produced all the elements up to iron (including, relevant to this particular case, oxygen), and then became supernovae, which a) produced traces of heavier elements b) blew a lot of stellar material out into the universe, to become part of new star systems. So there was oxygen around by the time Earth was formed (~4.5 billion years ago, as opposed to ~14 billion for the big bang).
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Re:Rosetta finds comet's water vapour to be significantly di... by aptwebapps on Thursday December 11, 2014 @01:22AM (#8733470)
CRC's GED prep book used to contain this error. Most of the book was good but the "Earth Science" section looked like it had been deliberately mangled in order to discredit opponents of creationism. Or that was my theory, anyway, it was pretty bad.
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Re:Rosetta finds comet's water vapour to be significantly di... by mkertajaya on Thursday December 11, 2014 @09:18AM (#8734786)
If you want to learn more, this is a valuable resource: https://www.bighistoryproject.com/ .
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Re:Rosetta finds comet's water vapour to be significantly di... by canvia on Thursday December 11, 2014 @11:05AM (#8735482)
The Cosmos series (either the old Sagan one or the new Neil DeGrasse Tyson one which is on Netflix) covers this in a very nice format.
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Re:Rosetta finds comet's water vapour to be significantly di... by ajuc on Thursday December 11, 2014 @06:32AM (#8734224)
But even if it ws too hot for liquid water the gravity of forming Earth would keep it as gas just as well as if it was liquid?
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Re:Rosetta finds comet's water vapour to be significantly di... by Datsundere on Wednesday December 10, 2014 @06:24PM (#8732325)
Wasn't our sun a product of a bigger star? Which is why we have the planets now.

http://en.wikipedia.org/wiki/Supernova_nucleosynthesis.

Nucleosynthesis says that at the end of the life of a star, heavier elemnts are formed as a byproduct.

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Re:Rosetta finds comet's water vapour to be significantly di... by ubernostrum on Wednesday December 10, 2014 @06:35PM (#8732372)
Nucleosynthesis gets you the heavier elements, but doesn't get around the "too hot to hold water" problem in Earth's early history.
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Re:Rosetta finds comet's water vapour to be significantly di... by tomr_stargazer on Wednesday December 10, 2014 @06:36PM (#8732377)
Yes, the heavy elements in our Solar System were formed inside previous generations of stars.
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