News1 min ago
Star Formation.
How can clouds of gas in the vacuum of space coalesce to produce the enormous pressures and temperatures necessary to begin fusion?
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For more on marking an answer as the "Best Answer", please visit our FAQ.Gravitational attraction plays a role. I'm not well-versed enough in stellar formation to give an answer impromptu, but as I remember it the basic starting point is that if you have enough gas and dust in a given area, and then set it in motion -- which is, for the record, inevitable, as perfectly static equilibrium is unstable above a certain amount of stuff -- then it will tend to fall coalesce around whatever the densest part of the cloud is. This is a self-reinforcing process, too -- as more matter falls in, the gravitational attraction increases.
At that point, it depends on how much matter you have to play with. If it's above a certain critical mass -- approximately 80 times that of Jupiter, I think -- then interesting stuff can happen; if not, then you get brown dwarfs or just a planet or some such.
At that point, it depends on how much matter you have to play with. If it's above a certain critical mass -- approximately 80 times that of Jupiter, I think -- then interesting stuff can happen; if not, then you get brown dwarfs or just a planet or some such.
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Theland does not really want an answer to this question.
Actually, correction, he wants a definitive answer to this question.....and the failure of ABers (or Science, in general) to be able to provide this will just serve to confirm his conviction that it must have been God wot dun it....
Science is creeping towards understanding and answering the 'big' questions and because we are not close enough, yet, doesn not mean that we will never get there.
Actually, correction, he wants a definitive answer to this question.....and the failure of ABers (or Science, in general) to be able to provide this will just serve to confirm his conviction that it must have been God wot dun it....
Science is creeping towards understanding and answering the 'big' questions and because we are not close enough, yet, doesn not mean that we will never get there.
It may be the case that the question is asked with a motivation beyond mere curiosity. On the other hand, more people than Theland will read the answer, so it doesn't matter whether the question was dishonest or not. It's particularly problematic when you haven't even allowed the questioner to speak for themselves -- yes, I'm aware that context is a thing, but the question as asked literally is "how do stars form?" In the first instance, answers, particularly in a thread purporting to be scientific in content, should obviously seek to address that, and anything else is an unhelpful distraction.
jack - // ... and the failure of ABers (or Science, in general) to be able to provide this will just serve to confirm his conviction that it must have been God wot dun it.... //
I have raised this self-same point many times, arguing that an absence of an explanation does not automatically indicate a divine creation.
I used the famous example of the fact that for hundreds of years, the flight of the bumble bee defied the then-known laws of aerodynamics, specifically, the bees' wing size measured against its body weight meant that it should not be able to fly, when clearly it does.
On the basis of the divine creation theory, that can be explained by offering that the bee is obeying God's laws of aerodynamics, rather than Man's.
But with the advent of previously unavailable stop-motion photography, it was discovered that the bee's fixed wings which could not support its weight, we not in fact fixed at all, but were rotatable, hence its ability to fly.
My point is simple - an unavailable explanation is not an indication of divine prescience, because in the fullness of time - not this century probably - but eventually, every phenomenon with no explanation at the time, will receive one, and will be understood.
That has applied thus far, from everything from the curvature of the earth, to eclipses of the sun, and what the moon is actually like when you walk on it.
Simply to say that because we can't explain something, it must be an Act of God is simply not valid, and history and science prove that beyond argument.
I have raised this self-same point many times, arguing that an absence of an explanation does not automatically indicate a divine creation.
I used the famous example of the fact that for hundreds of years, the flight of the bumble bee defied the then-known laws of aerodynamics, specifically, the bees' wing size measured against its body weight meant that it should not be able to fly, when clearly it does.
On the basis of the divine creation theory, that can be explained by offering that the bee is obeying God's laws of aerodynamics, rather than Man's.
But with the advent of previously unavailable stop-motion photography, it was discovered that the bee's fixed wings which could not support its weight, we not in fact fixed at all, but were rotatable, hence its ability to fly.
My point is simple - an unavailable explanation is not an indication of divine prescience, because in the fullness of time - not this century probably - but eventually, every phenomenon with no explanation at the time, will receive one, and will be understood.
That has applied thus far, from everything from the curvature of the earth, to eclipses of the sun, and what the moon is actually like when you walk on it.
Simply to say that because we can't explain something, it must be an Act of God is simply not valid, and history and science prove that beyond argument.
Mamya - // It doesn't matter to me why he's asking, I'm interested in the answers on the question as it stands - aren't you? //
No I'm not remotely interested in the answer to the OP - but I am interested in why Theland is asking it, as I have pointed out, and that is an answer I would like to read.
No I'm not remotely interested in the answer to the OP - but I am interested in why Theland is asking it, as I have pointed out, and that is an answer I would like to read.
// I used the famous example of the fact that for hundreds of years, the flight of the bumble bee defied the then-known laws of aerodynamics ... //
You're using a famous example that is also, sadly, mistaken. The idea that aerodynamics predicted that bumblebees should be unable to fly is a complete myth, dating back to the 1930s when a single scientist made a bad calculation. Although he swiftly corrected it, the bad calculation spread faster, as is often the case, than the correct one. If you take nothing else from this thread, take that point -- the point you're making using the example is of course valid -- ie, that science is constantly progressing -- but the example isn't.
You're using a famous example that is also, sadly, mistaken. The idea that aerodynamics predicted that bumblebees should be unable to fly is a complete myth, dating back to the 1930s when a single scientist made a bad calculation. Although he swiftly corrected it, the bad calculation spread faster, as is often the case, than the correct one. If you take nothing else from this thread, take that point -- the point you're making using the example is of course valid -- ie, that science is constantly progressing -- but the example isn't.