The Cambrian problem

[pat34lee]

Your objections look refuted to me. I haven't seen you respond to posts refuting them.

When someone tells you that X is wrong because John Doe says,
is that a refutation worth responding to?

 

[pat34lee]

But you understand everything and lecture real scientists about their many errors.

No, just people who believe in fairy stories just because
they have the name science tacked to them.

 

[Paulos23]

When someone tells you that X is wrong because John Doe says,
is that a refutation worth responding to?

If John Doe is an expert on the subject, yes.

Your problem with gas not being able to condense to make a star doesn't seam to work. What makes gas uncompressible by gravity? Given enough time gravity of the gas will bring it together. If enough comes together it ignites and makes a star.

I have not seen you give a good reason that gas can't collect in big enough amounts to do this.

 

[pat34lee]

As I have been saying

Slow gravitational collapse and the ideal gas law
The slow gravitational collapse model holds that a star's fuel collapses gradually under its own gravity. However, this model is physically impossible, because gas spreads indefinitely in a vacuum, because its expansion pressure outweighs its gravity.

The Ideal gas law states:
pV=nRT

where: p is the pressure; V is the volume; n is the number of moles; R=0.0821 L atm mol-1 K-1 (that is, R is the gas constant); T is the temperature.

According to this law, which we all learned in high school chemistry: where nRT is finite (as it always is for any given amount of gas), and pressure approaches zero (as it is in the vacuum of space), V approaches infinity. That is, a gas will spread indefinitely in a vacuum.
Further, as T increases (as it must if a hydrogen cloud is to grow warmer on its way toward fusion), the expansion pressure of the gas cloud will increase. In other words, the warmer the hydrogen cloud gets, the more it will spread.
http://creationwiki.org/Star_formation

 

[Paulos23]

So you are saying that gas is not affected by gravity???

 

[pat34lee]

The fairly simple formula for Jeans' Length (Sir James Jeans) shows what is necessary for stellar formation. A gas cloud must be within a critical radius in order to collapse by gravity (Jeans' Length). Jeans' Length (JL) is equal to the Gravitational constant (G) times the mass (M) of the cloud squared, divided by two times the number of moles of gas, times the Gas Constant (R), times the Temperature (T) in kelvins (see Table below). {5} There are other ways to calculate the physical parameters for star formation, but similar problems develop. Leo Blitz says that about 99 percent of the mass of a Giant Molecular Cloud (where stars are thought to form) is molecular hydrogen, H2. {6} I used this fact to calculate the minimum number of moles (n) of hydrogen that would have formed the core of the sun and solved for T. The temperature that the sun's equivalent cloud mass would have to be in order for it to contract under the force of gravity, considering the mass of the Sun, expanding its radius to the distance of one light year, and plugging in the values for the constants. The result was 1.69 degrees K (- 456.68 degrees F. Absolute Zero, 0 degrees K = - 459.67 degrees F), one degree less than the temperature of the 2.726 degrees K cosmic background radiation, according to the latest COBE satellite measurements. {7} The universe is too hot for star formation!

5. DeYoung, Donald B. and John C. Whitcomb, "The Origin of the Universe," Design and Origins in Astronomy, George Mulfinger editor, Creation Research Society, 1983. p. 17

6. Blitz, Leo, "Giant Molecular-Cloud Complexes in the Galaxy," Scientific American, Apr. 1982, p. 86

7. Cown, Ron, "COBE: A Match Made in Heaven," Science News, 143 (1993), p. 43.

http://www.ldolphin.org/stars.html

 

[pat34lee]

So you are saying that gas is not affected by gravity???

As I said early on, gravity is a weak force, not a strong one.
It is not enough to overcome the kinetic energy that forces
gas to disperse.

 

[Paulos23]

As I said early on, gravity is a weak force, not a strong one.
It is not enough to overcome the kinetic energy that forces
gas to disperse.

What kinetic energy? If you are talking about from a star exploding, yes some of the gas does escape, but most of the gravitational attraction of the total of gas is enough to keep most of it in the area. Gravity is weak, but it attracts over long distances and does not stop. A bulk of the gas still comes back in to make smaller stars. And if it is lucky, there may be more gas nearby from another star exploding to add to it.

Your suggesting that gas never collects into large masses, which our own gas giants refute.

 

[pat34lee]

Your suggesting that gas never collects into large masses, which our own gas giants refute.

That is like saying evolution is proven because we have trees.
Gas giants only prove that there are gas giants. We don't have
instructions on how they were made.

 

[sfs]

The fairly simple formula for Jeans' Length (Sir James Jeans) shows what is necessary for stellar formation. A gas cloud must be within a critical radius in order to collapse by gravity (Jeans' Length). Jeans' Length (JL) is equal to the Gravitational constant (G) times the mass (M) of the cloud squared, divided by two times the number of moles of gas, times the Gas Constant (R), times the Temperature (T) in kelvins (see Table below). {5} There are other ways to calculate the physical parameters for star formation, but similar problems develop. Leo Blitz says that about 99 percent of the mass of a Giant Molecular Cloud (where stars are thought to form) is molecular hydrogen, H2. {6} I used this fact to calculate the minimum number of moles (n) of hydrogen that would have formed the core of the sun and solved for T. The temperature that the sun's equivalent cloud mass would have to be in order for it to contract under the force of gravity, considering the mass of the Sun, expanding its radius to the distance of one light year, and plugging in the values for the constants. The result was 1.69 degrees K (- 456.68 degrees F. Absolute Zero, 0 degrees K = - 459.67 degrees F), one degree less than the temperature of the 2.726 degrees K cosmic background radiation, according to the latest COBE satellite measurements. {7} The universe is too hot for star formation!

5. DeYoung, Donald B. and John C. Whitcomb, "The Origin of the Universe," Design and Origins in Astronomy, George Mulfinger editor, Creation Research Society, 1983. p. 17

6. Blitz, Leo, "Giant Molecular-Cloud Complexes in the Galaxy," Scientific American, Apr. 1982, p. 86

7. Cown, Ron, "COBE: A Match Made in Heaven," Science News, 143 (1993), p. 43.

http://www.ldolphin.org/stars.html

Why would he consider a volume of gas with only one solar mass? Every model of stellar formation I've ever seen has started with a much larger cloud. Larger clouds mean stronger gravity.

 

[Dr GS Hurd]

5. DeYoung, Donald B. and John C. Whitcomb, "The Origin of the Universe," Design and Origins in Astronomy, George Mulfinger editor, Creation Research Society, 1983. p. 17

6. Blitz, Leo, "Giant Molecular-Cloud Complexes in the Galaxy," Scientific American, Apr. 1982, p. 86

7. Cown, Ron, "COBE: A Match Made in Heaven," Science News, 143 (1993), p. 43.

Why not try some recent studies?

NASA: Cosmology: The Study of the Universe

 

[Dr GS Hurd]

Why would he consider a volume of gas with only one solar mass? Every model of stellar formation I've ever seen has started with a much larger cloud. Larger clouds mean stronger gravity.

From my reading, small stars need a "kick start" which is commonly a nearby super nova. For our solar system this would also explain some radioisotope ratios.

 

[lesliedellow]

Two things.

The densities of gas on earth are many times that of space.
Why don't stars form in our atmosphere?
Jupiter and Saturn have even denser atmospheres.
Why aren't they stars?

Because the Sun is pumping in energy, giving the gas molecules more than enough kinetic energy to defy gravity.

 

[Shemjaza]

Two things.

The densities of gas on earth are many times that of space.
Why don't stars form in our atmosphere?
Jupiter and Saturn have even denser atmospheres.
Why aren't they stars?

The point at which a gas collapses into a star is theoretical.
It has never been observed.
Why do you accept it as fact with no proof it
ever happened?
or could happen?

Even your side's scientists are saying current theories
are probably wrong.
http://www.space.com/12788-impossible-star-defies-theory.html

You know that nebula have a much, much higher mass then even the biggest of planets, right?

 

[pat34lee]

Why would he consider a volume of gas with only one solar mass? Every model of stellar formation I've ever seen has started with a much larger cloud. Larger clouds mean stronger gravity.

If you start with fairies, you can do anything with math.
In reality, you have to begin with numbers likely to be
found in nature, not begin with what you think you need.

 

[pat34lee]

You know that nebula have a much, much higher mass then even the biggest of planets, right?

Mass doesn't mean much if it is spread over 1/2 a light year.
Density is the important thing.

 

[pat34lee]

Why not try some recent studies?
(I know why- they busted your little fantasy world).

What, if anything, is new in them?

 

[lasthero]

What, if anything, is new in them?

Why don't you read them and find out?

 

[Astrophile]

The densities of gas on earth are many times that of space. Why don't stars form in our atmosphere?

It is easy enough to calculate the Jeans mass for the Earth's atmosphere; it is 3.3×10^22 kg, about 6600 times the mass of the atmosphere. Thus the Earth's atmosphere is not massive enough to contract under its own weight.
You do not appear to understand that it is the total mass of the gas cloud that is crucial, not the particle density. If you look at the formulae that sfs kindly provided, you will see that whatever density you assign the gas there will be a radius and mass above which the cloud will contract.

Jupiter and Saturn have even denser atmospheres.
Why aren't they stars?

This is a good question, but you are approaching it from the wrong starting point.
The interiors of Jupiter and Saturn are not perfect gas; their interiors consist of metallic hydrogen, which is able to support the pressure of the overlying layers. Thus the gas laws do not apply to them. Stars do consist of perfect gases; they are compressible, and it is only their internal energy (i.e. their high temperature) that prevents them from collapsing catastrophically under their own weight.

The odd thing here is that 19th-century physicists such as Lord Kelvin and Hermann von Helmholtz knew that stars would contract and heat up under their own gravitational force; indeed, they proposed that the stars shine as a result of generating energy by contraction; they showed that the lifespan of a solar-mass star with no other source of energy would be 20-25 million years.

To go back to the essential point, the energy that heats the contracting cloud and raises its temperature comes from the gravitational potential energy of the cloud. If the negative gravitational energy of the cloud exceeds its positive internal energy (i.e. if the total energy of the cloud is negative), the cloud will contract. The contraction results in a decrease in the potential energy, which balances the increase in the internal energy (the temperature of the cloud). By the principle of conservation of energy, the negative potential energy still exceeds the positive internal energy, and the total energy of the cloud remains negative.

However, you are partly right. Star formation is an inefficient process; only a small proportion of the mass of even a dense interstellar cloud contracts to form stars. Most of the cloud is dispersed, through stellar winds and through heating by stellar radiation. Also, protostars embedded in dark clouds are associated with strong bipolar outflows, with mass losses of 10^-7 to 10^-8 solar masses per year.

However, the fact that part of the cloud is dispersed doesn't mean that all of it is, or that contraction of a small part of the cloud is impossible. Indeed, the bipolar outflows and the dispersing cloud material carry energy away with them, thereby further decreasing the potential energy of the remainder of the cloud and accelerating its contraction.

The point at which a gas collapses into a star is theoretical.
It has never been observed.
Why do you accept it as fact with no proof it
ever happened?
or could happen?

There is abundant empirical evidence for the formation of stars from interstellar clouds. Short-lived stars, such as high-luminosity O and early B-type stars, and stars in short-lived stages of their lives, such as T Tauri stars, are invariably associated with interstellar clouds; they are not found away from these clouds. To cite three examples, the Trapezium, the Becklin-Neugebauer object (a massive young star) and the Kleinmann-Low nebula (a very young star cluster) are in the Orion Molecular Cloud-1; the young cluster NGC 2264 in Monoceros is associated with the dark cloud of the Cone Nebula; and the cluster M16 (NGC 6611) is associated with the dark clouds that form the 'Pillars of Creation'. How do you explain this invariable association of these young stars and young stars clusters with interstellar clouds if the stars are not born from the clouds?

 

[Astrophile]

The fairly simple formula for Jeans' Length (Sir James Jeans) shows what is necessary for stellar formation. A gas cloud must be within a critical radius in order to collapse by gravity (Jeans' Length). Jeans' Length (JL) is equal to the Gravitational constant (G) times the mass (M) of the cloud squared, divided by two times the number of moles of gas, times the Gas Constant (R), times the Temperature (T) in kelvins (see Table below). {5} There are other ways to calculate the physical parameters for star formation, but similar problems develop. Leo Blitz says that about 99 percent of the mass of a Giant Molecular Cloud (where stars are thought to form) is molecular hydrogen, H2. {6} I used this fact to calculate the minimum number of moles (n) of hydrogen that would have formed the core of the sun and solved for T. The temperature that the sun's equivalent cloud mass would have to be in order for it to contract under the force of gravity, considering the mass of the Sun, expanding its radius to the distance of one light year, and plugging in the values for the constants. The result was 1.69 degrees K (- 456.68 degrees F. Absolute Zero, 0 degrees K = - 459.67 degrees F), one degree less than the temperature of the 2.726 degrees K cosmic background radiation, according to the latest COBE satellite measurements. {7} The universe is too hot for star formation!

5. DeYoung, Donald B. and John C. Whitcomb, "The Origin of the Universe," Design and Origins in Astronomy, George Mulfinger editor, Creation Research Society, 1983. p. 17

6. Blitz, Leo, "Giant Molecular-Cloud Complexes in the Galaxy," Scientific American, Apr. 1982, p. 86

7. Cown, Ron, "COBE: A Match Made in Heaven," Science News, 143 (1993), p. 43.

http://www.ldolphin.org/stars.html

Again, you are missing the point that it is the total mass of a cloud that is important. To give a well-known example, the Coalsack dark nebula in Crux has a diameter of about 18 parsecs and a mass of about 3500 solar masses. This is much larger than the 1-light-year and 1 solar mass cloud that you are imagining. The number density of the cloud is about 24 H2 molecules /cm³, and the Jeans mass (for T = 30 K) is about 130 solar masses. Thus the mass of the Coalsack is larger than the Jeans mass, and therefore the cloud must contract.