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When The Stars Go Out (Astrophysics)
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Mick Harper
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The life cycle of a star depends upon its mass. High mass stars are much brighter than low mass stars, thus they rapidly burn through their supply of hydrogen fuel. A star like the Sun has enough fuel in its core to burn at its current brightness for approximately 9 billion years. A star that is twice as massive as the Sun will burn through its fuel supply in only 800 million years. A 10 solar mass star, a star that is 10 times more massive than the Sun, burns nearly a thousand times brighter and has only a 20 million year fuel supply. Conversely, a star that is half as massive as the Sun burns slowly enough for its fuel to last more than 20 billion years.

I've just realised where Dan and orthodoxy have gone wrong about all this big vs little star-burning stuff. Let's start with Star A (which is very big) and Star B (which is quite small), light the blue touch paper and retire to watch from a safe distance.

Now Star A will burn furiously because it has to obey The Dictates of Dan, whereas Star B will burn rather slowly. In n million/billion years Star A will have burnt so furiously that it will now be down to the size of Star B whereupon, by definition ex hypothesi etc etc, it will also start burning at the rate of of Star B.

So they will fizzle out at exactly the same moment in time!

This shalt be known as Harper's Law of Stars Fizzling Out All At The Same Time.
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L R B Quirke


In: Auckland, New Zealand
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Come on! Surely it depends on when they started.
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Mick Harper
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In: London
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I'm not so sure that it does. I always get confused by Zeno's Paradox but let's go back to Star A and Star B. So long as the larger one does not start and stop before the small one even comes into existence, does it not follow that the quicker-burning one will by definition 'pass' the smaller one? But of course it cannot pass it for, at that moment, it will be of the same size and therefore of the same burn-rate as the smaller one, and thus will conform with its burn-rate. And therefore they will go out at the same time.

And while we're on the subject, surely it must be that stars ignite at the same size too? After all they are just agglumulating blobs of hydrogen so I don't see what else apart from mass can cause the ignition. So all stars must last the same length of time. Since we don't what that length of time is I shall merely call this Harper's Constant.
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john w robertson


In: Southern Scotland
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I'm no scientist, but is it possible that:

(i) the fast-burning big star keeps burning faster than the smaller one even when they're the same size because of some kind of built up energy (no scientist I know)?

(ii) more than hydrogen is burning and this differs from star-to-star?
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DPCrisp


In: Bedfordshire
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Here are a few orthodox quotes on the subject if it will help..

"Larger stars generally burn faster and hotter, smaller stars burn more gently and for longer."

"Small stars are less hot in their cores. The rate of nuclear burning depends very sensitively on the core temperature: increase the mass only a little, giving only a small increase in core temperature, and you get a great increase in the rate of burning. So large stars burn up much faster than small ones."

"The more massive stars burn hydrogen more rapidly than do the less massive ones and so they evolve more rapidly. The structure of the star changes and it evolves off the main-sequence to become a sub-giant and then a giant star. Eventually, nuclear reactions involving helium occur in the core; the way in which this occurs and the resulting changes in the stellar structure depend on the initial stellar mass."

"Blue or even blue/green stars are very hot up to 50,000°C and are normally giant young stars which are very active or even 'hyper-active'. They are all young because they don't live very long. They live very active short lives and die young usually in a massive explosion called a Super Nova."

"The life cycle of a star depends upon its mass. High mass stars are much brighter than low mass stars, thus they rapidly burn through their supply of hydrogen fuel. A star like the Sun has enough fuel in its core to burn at its current brightness for approximately 9 billion years. A star that is twice as massive as the Sun will burn through its fuel supply in only 800 million years. A 10 solar mass star, a star that is 10 times more massive than the Sun, burns nearly a thousand times brighter and has only a 20 million year fuel supply. Conversely, a star that is half as massive as the Sun burns slowly enough for its fuel to last more than 20 billion years."

From these figures, the life-time of a star is evidently reckoned to be inversely proportional to the mass (more than) squared. {T ~ 5e9M^-2.4}

By way of analogy, consider a power supply. For a given power output, current (amps) is inversely proportional to voltage (volts). Theoretically, that means any power supply can give a billion volts at a very low current... or a billion amps at a very low voltage. But in reality, the output is also limited to, say, no more than 240 volts and, say, no more than 10 amps.
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Mick Harper
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ii) more than hydrogen is burning and this differs from star-to-star?

Surely not. I dunno how it all works but there's only hydrogen and helium involved and the one is being turned into the other by the process of burning.

Is it true, for instance, that it is only the hydrogen that burns and that the helium is simply an inert by-product? If this is the case then Harper's Constant will work because the hydrogen levels in the two stars will eventually match. This is inevitable if it is true that the more the hydrogen, the quicker it burns....agreed?

However if the helium acts as a moderating agent, then the Big Star will be saddled by an excess of helium when they reach the same mass. But then surely it is true that the small star will simply take over as the leading-burner until its mix of hydrogen and helium is the equivalent (I accept that probably they will never be the same in totals) in burn-rate terms to the Big One. Whereupon they will burn down together, by definition.

Something like that. I am beginning to think there is a bigger principle behind all this. After all it is an Applied Epistemological principle that orthodoxy always makes up theories depending on what can be seen while never thinking about what can't be seen. Hence the fact that from our particular vantage point (in time as well as space) we see all different stars in all different states. But we would see that exact same thing, would we not, if every star began at the same size, lasted exactly the same length of time but started at different times.
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Komorikid


In: Gold Coast, Australia
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Harper's Constant can only explain the life cycles of stars IF they are self-immolating hydrogen balls producing energy by thermonuclear fusion.

The current evidence from both Earth observation and collected scientific data from space says they could not possibly be. The evidence at hand completely contradicts Eddington's original proposal (the currently held paradigm). Stars cannot possibly be thermonuclear fusion reactors composed of hydrogen.

Not one single prediction posited by Eddington or his legion of devotees in modern stellar astronomy has come to pass. Every one has been falsified by observation and empirical data. At the fundamental level of basic thermodynamics and gravity the Sun works in the exact opposite way to that predicted.
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Hatty
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In n million/billion years Star A will have burnt so furiously that it will now be down to the size of Star B whereupon, by definition ex hypothesi etc etc, it will also start burning at the rate of of Star B.

So they will fizzle out at exactly the same moment in time
!

If they burn out simultaneously, what stops all the remaining stars sticking together afterwards by virtue of mutual gravitation (or even getting swallowed by their still-active "sun")? This should happen much more quickly because they are closer together and the gravitational force is subject to the inverse square law.

This "clumping" is indeed happening according to a BBC Science report http://news.bbc.co.uk/2/hi/science/nature/7326318.stm in which observers conclude a new planet is being formed from "super-large dust".

According to one model, planets form from the bottom up. Under this scenario, particles of rocky material collide and "stick" to one another, forming a bigger and bigger object.

But he thinks the proto-planet in HL Tau formed relatively quickly when a region of the disc collapsed to form a self-contained structure. This could occur because of gravitational instability in the disc itself.
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Mick Harper
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In: London
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If they burn out simultaneously,

No, no! Harper's Constant says that all stars burn for the same length of time, not that they will go out simultaneously.

what stops all the remaining stars sticking together afterwards by virtue of mutual gravitation (or even getting swallowed by their still-active "sun")?

Well, this is a huge problem for orthodoxy, whether stars are active or non-active since gravity is one-way-street. And one in the plus column for the Electric Universe since at least they have a repelling force.

In my DVD I put forward the notion that spinning galaxies are nature's way of stopping the final 'clumping' just as the spinning of the Solar System ensures that the bodies of the Solar System remain apart (just about....of course they have clumped a remarkable amount already getting to where they are today!).
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Ishmael


In: Toronto
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Komorikid wrote:
Not one single prediction posited by Eddington or his legion of devotees in modern stellar astronomy has come to pass.

Well except one. The burnt-out iron and silicate cores that litter the universe.
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Komorikid


In: Gold Coast, Australia
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Ish wrote:

Well except one. The burnt-out iron and silicate cores that litter the universe.

No it's not Eddington's prediction it's Mick's via SCUM
He just uses the Eddington's Standard Orthodox Model of the Sun to predict a different outcome.
If the Standard Orthodox Model is invalid so is SCUM.
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Brian Ambrose



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A bit of info about Mars, from the Society for Popular Astronomy. Strange that Earth's sibling should exhibit such different internal properties as described below. Seems Mars is internally very active. In terms of SCUM, is there any significance to methane?

MARTIAN METHANE NOT UNDERSTOOD
ESA

The discovery some years ago of methane in the Martian atmosphere was a surprise. Much of the methane in the Earth's atmosphere is of biological origin, but some is contributed by vulcanism. Methane is thought to be stable in the Martian atmosphere for around 300 years.

It follows that the observed methane must have been generated within the last few hundred years. Recently, people at Goddard Space Flight Center have said that the methane that they saw in 2003 was concentrated in three particular regions. That showed that it must have been released so recently that it had not had time to distribute itself around the planet.

Moreover, instead of taking 300 years to disappear, it had almost entirely vanished by early 2006. Now, atmospheric physicists have tried to model Mars' climate, but their models are unable to reproduce the behaviour of the methane.

Something seems to be removing the methane from the atmosphere 600 times faster than the models can account for. That might suggest that the source must be 600 times more intense than was originally assumed, which is considerable even by terrestrial standards
.
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Mick Harper
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In terms of SCUM, is there any significance to methane?

SCUM claims that there ought to be carbon still hanging around in stars that aren't as advanced as Earth. It is true that both Earth and Mars are presumably at the iron stage but if Mars is a great deal younger than the Earth then the four billion years that it has taken Earth to get rid of nuclear-fusion produced carbon (inimical to life in large amounts) and then produce life (which in turn produces ordinary trace bio-methane) hasn't yet elapsed on Mars.

Neptune and Uranus are examples of stars that are even younger than Mars ie the methane is present in huge amounts signalling that either they are just entering the Carbon stage of the Hydrogen-Helium-Carbon life-cycle or they are further along and the carbon is still hanging around. (I forget the actual stages...could someone remind me?)
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Brian Ambrose



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This may be of particular interest to Ishmael.

EXTRA-SOLAR PLANET OUGHT NOT TO EXIST
Science Daily

A photometric survey called WASP has discovered a planet that has ten times the mass of Jupiter but orbits its star in less than a day. That poses a challenge to the experts' understanding of tidal interactions in planetary systems. The planet, called WASP-18b,
belongs to a now-common class of extra-solar planets known as 'hot Jupiters'. It is so massive, and so close to its star -- only about three stellar radii away -- that tidal interactions between star and planet ought to cause the planet to spiral inwards to its destruction in less than a million years. Yet, astronomers think that the WASP-18 parent star is about a billion years old, so either we have to admit that the likelihood of catching sight of WASP-18b at this critical time is only about one in a thousand, or else tidal dissipation in the WASP-18 system somehow manages to be a thousand times less than in our Solar System. If the planet's remaining existence is as short as predicted, the orbital decay should be measurable within a decade.

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Ishmael


In: Toronto
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Brian Ambrose wrote:
This may be of particular interest to Ishmael.


It probably would be, if I understood it.

Alas. The task of unraveling the secrets of the universe has fallen to an individual of middling intelligence.
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