Spiral Galaxy –How it had been formed?

[David Levy]

By Wiki: "The Milky Way began as one or several small overdensities in the mass distribution in the Universe shortly after the Big Bang. Some of these overdensities were the seeds of globular clusters in which the oldest remaining stars in what is now the Milky Way formed. These stars and clusters now comprise the stellar halo of the Galaxy. Within a few billion years of the birth of the first stars, the mass of the Milky Way was large enough so that it was spinning relatively quickly. Due to conservation of angular momentum, this led the gaseous interstellar medium to collapse from a roughly spheroidal shape to a disk. Therefore, later generations of stars formed in this spiral disk. Most younger stars, including the Sun, are observed to be in the disk."

 

Questions:

1. Black hole - In this explanation there is not even one word about the supper massive black hole – When and how it had been created?
2. Spinning – In the Milky Way there are about 400 Billion stars. Even if we put them together, it is clear that each one might have a different velocity, phase & direction. How come that the mass of those stars can suddenly triggered them all spinning in one direction and at high velocity???
3. Escape – Actually, if the stars will start spinning, we would expect that most of them would be thrown out of the stellar halo galaxy. Do you agree?
4. The mass of the black hole – Scientists claim that the mass of the supper massive black hole is too small compared to its housing spiral galaxy. So how it could even start the momentum?
5. Disk shape & spiral arms – There is no glue between the stars, so how the conservation of angular momentum could set the disk shape and the spiral arms without the requested power which is needed to hold them together?

[EdEarl]

The Milky Way article in Wikipedia does discuss the super massive black hole at the center of our galaxy. It also discusses that dark matter may explain why the rotation of stars around the galaxy contradict Keplerian dynamics. Thus, the article does address your five questions. On the other hand, very little is know about DM, and for that reason it is little more than a euphemism instead of a complete and accurate description of what holds galaxies together. That is not a criticism of science or scientists, it is an assessment of the knowledge about DM, an incredibly elusive phenomenon.

[J.C.MacSwell]

By Wiki: "The Milky Way began as one or several small overdensities in the mass distribution in the Universe shortly after the Big Bang. Some of these overdensities were the seeds of globular clusters in which the oldest remaining stars in what is now the Milky Way formed. These stars and clusters now comprise the stellar halo of the Galaxy. Within a few billion years of the birth of the first stars, the mass of the Milky Way was large enough so that it was spinning relatively quickly. Due to conservation of angular momentum, this led the gaseous interstellar medium to collapse from a roughly spheroidal shape to a disk. Therefore, later generations of stars formed in this spiral disk. Most younger stars, including the Sun, are observed to be in the disk."

 

Questions:

1. Black hole - In this explanation there is not even one word about the supper massive black hole – When and how it had been created?
2. Spinning – In the Milky Way there are about 400 Billion stars. Even if we put them together, it is clear that each one might have a different velocity, phase & direction. How come that the mass of those stars can suddenly triggered them all spinning in one direction and at high velocity???
3. Escape – Actually, if the stars will start spinning, we would expect that most of them would be thrown out of the stellar halo galaxy. Do you agree?
4. The mass of the black hole – Scientists claim that the mass of the supper massive black hole is too small compared to its housing spiral galaxy. So how it could even start the momentum?
5. Disk shape & spiral arms – There is no glue between the stars, so how the conservation of angular momentum could set the disk shape and the spiral arms without the requested power which is needed to hold them together?

 

 

 

1. Short but incomplete answer is that there was gravitational accretion of enough mass in a sufficiently small area to create it. The potential had to be there.

 

2. There had to be the same net angular momentum prior. The velocity would have to increase to maintain it, with the energy for the increased velocities coming from the gravitational potential and subsequent accretion

 

3. No. Stars moving too fast would move outward, slowing them down. The general trend would be gravitational accretion, but faster moving stars would not join in, until slowed by the system, their kinetic energy taken in part by other stars. A few might escape by randomly bucking the general trend, but most would only move outward temporarily.

 

4. Not sure where the extra mass that is required is, but I don't believe a Super massive Black Hole was necessary to start the process. It probably came about as part of it.

 

5. I think the "glue" is gravity. The stars are close enough in each arm to be gravitationally bound and not orbit the galaxy independently, yet not so gravitationally bound or so close together that they form a separate orbital system.

Edited June 29, 2013 by J.C.MacSwell

[David Levy]

Hi EdEarl

 

There is no explanation how a supper massive black hole had been created!!!

Just by putting together billion stars would not create a black hole. Without a real supper massive black hole there is no existence for a spiral galaxy!

In order to set a spiral galaxy a full Coordination between the size of galaxy, the mass of the black hole and the velocity of the spinning is needed.

If a black hole had been created by some sort of magic power while the spinning velocity is too low, then it would probably eliminate all the stars which might be in the aria of its gravity force.

if the black hole had been created while the spinning velocity is too high, then the stars would probably drift out of the clusters before setting the spiral galaxy.

Therefore, the chance to set spiral galaxy out of clusters of 400 billion stars is virtually zero!!!

Edited June 29, 2013 by David Levy

[EdEarl]

There is no explanation how a supper massive black hole had been created!!!

No one is sure how super massive black holes are created.

[D H]

Therefore, the chance to set spiral galaxy out of clusters of 400 billion stars is virtually zero!!!

 

Anywhere you look you'll see spiral galaxies. Lots and lots and lots of them. Therefore, the chance that your logic is correct is virtually zero!!!

 

So let's look at this logic.

 

 

Questions:

• Black hole - In this explanation there is not even one word about the supper massive black hole – When and how it had been created?
• Spinning – In the Milky Way there are about 400 Billion stars. Even if we put them together, it is clear that each one might have a different velocity, phase & direction. How come that the mass of those stars can suddenly triggered them all spinning in one direction and at high velocity???
• Escape – Actually, if the stars will start spinning, we would expect that most of them would be thrown out of the stellar halo galaxy. Do you agree?
• The mass of the black hole – Scientists claim that the mass of the supper massive black hole is too small compared to its housing spiral galaxy. So how it could even start the momentum?
• Disk shape & spiral arms – There is no glue between the stars, so how the conservation of angular momentum could set the disk shape and the spiral arms without the requested power which is needed to hold them together?

 

1. Astronomers and cosmologists don't know which came first, supermassive black holes, galaxies, or stars. A couple of things are certain. One is that those supermassive black holes were present very shortly after galaxies first started forming, and they might have been present before then. The other is that those supermassive black holes played a key role in the formation and evolution of galaxies.

 

2. Spinning - The fact that you are using "spinning" rather than orbiting is a dead giveaway that you don't know what you're talking about. You also apparently don't know what angular momentum is.

 

3. Escape - You apparently don't know what energy is, either.

 

4. What are you talking about? What scientists? Citation needed, please.

 

5. There is no glue between the stars? Really? Of course there is. It's called gravity.

[David Levy]

Hello D H

D H: "Astronomers and cosmologists don't know which came first, supermassive black holes, galaxies, or stars." If they don't know which came first, how do they know how a spiral galaxy had been created?

D M: "A couple of things are certain. One is that those supermassive black holes were present very shortly after galaxies first started forming, and they might have been present before then." Again, the science has no clue how, why and when the black hole had been created… Please be aware that it's mass is huge. By Wiki: " A supermassive black hole (SMBH) is the largest type of black hole, on the order of hundreds of thousands to billions of solar masses."

Therefore, by definition this mass might be much bigger than any expected early global clusters & stars. Hence, there is no logical way that a stellar halo can support the requested mass for the suppermassive black hole as well as all the stars in the spiral galaxy as a milky way and Andromeda.

Please also be aware that t is also a rotational black hole. Its high rotational movement creates the famous bar shape as well as the spiral arms. Therefore, all the stars in the spiral arms actually follow the spin power which is generated by the black hole – and not vice versa.

Hence, the Idea that angular momentum could generate this kind of momentum in the black hole is not so logical.

D M: "The other is that those supermassive black holes played a key role in the formation and evolution of galaxies". Yes, sure. But again it might be an impossible mission to create this kind of object out of the available mass and star in the halo.

D M : "4. What are you talking about? What scientists? Citation needed, please." Please see the message from Spyman: " Also even though supermassive black holes holds a impressive amount of mass/energy they are still very small compared to their housing galaxy". http://www.scienceforums.net/topic/77126-how-thick-is-our-spiral-arm/

Two more issues to consider:

1. If it happened in the past, we would expect that it should happen again. There are billions over billions global clusters and staler halo in the space. Unfortunately for this illogical theory… the science couldn't find even one that is in a transient phase of converting to spiral galaxy. Why the "angular momentum" is not working anymore???
2. Spiral arms: The science still wonders how the spiral arms had been created. " Some recent studies have explored the likelihood that spiral galaxies with a close neighbor (a nearby dwarf galaxy, for example) get their arms as gravity from the satellite galaxy pulls on the disk of its neighbor." Just think what could be the results for a spiral galaxy without at spiral arms. The Angular Momentum can't give any real explanation how the spiral arms had been created. Without the spiral arms – there is no existence for a spiral galaxy.

Therefore, currently, the science has no solid theory for spiral galaxy formation.

The atom creation Theory is the ultimate answer for what we see in space!!!

[D H]

Hello D H

D H: "Astronomers and cosmologists don't know which came first, supermassive black holes, galaxies, or stars."

Learn to use the quote button.

 

 

If they don't know which came first, how do they know how a spiral galaxy had been created?

 

Huh? That's a non sequitur. Nope. It's not even a non sequitur. Calling this a non sequitur would imply that you have some kind of logic, just badly done. You don't. It's not a sequitur at all.

 

 

Astronomy is first and foremost an observational science. Astronomers classify galaxies as spiral, elliptical, or irregular based on what they observe. For any given galaxy they have but one observation of that galaxy, what they see now. Astronomers cannot see how or when a specific galaxy was created, nor can they see how it evolved.

 

You appear to be under the assumption that a galaxy that is currently observed to be a spiral galaxy was always a spiral galaxy. That apparently is not the case. Over 2/3 of the close-by galaxies are spiral galaxies. Look further away (look further into the past) and the fraction of galaxies that are spiral galaxies drops. Look very far away, for example the Hubble deep field, and the fraction drops to less than 1/3. See R. Delgado-Serrano, et al, 2010, How was the Hubble Sequence, 6 Giga-years ago?, Astronomy & Astrophysics, 509, A78. Arxiv preprint: http://arxiv.org/abs/0906.2805.

 

So how to explain this change? One simple solution is that spiral galaxies are the consequence of galactic mergers. See F. Hammer et al., 2009, The Hubble Sequence: just a vestige of merger events?, Astronomy & Astrophysics, 507, 1313. Arxiv preprint: http://arxiv.org/abs/0903.3962.

 

 

Therefore, by definition this mass might be much bigger than any expected early global clusters & stars. Hence, there is no logical way that a stellar halo can support the requested mass for the suppermassive black hole as well as all the stars in the spiral galaxy as a milky way and Andromeda.

 

That's another not even a non sequitur. I suggest you stop using your non-logic and start using mathematics.

 

Another thing I suggest you stop doing is looking for root causes. There are two big unknowns in astronomy: Dark mass and dark energy. Dark energy isn't a big concern for galaxies; it rears it's ugly head only for very large scale structures.

 

Dark mass is a huge concern with regard to galaxies. Scientists don't know what dark mass is. They don't even whether it truly exists; a small minority of scientists still advocate that some modification to how gravity works at galactic scale is the solution to the dark mass problem. Until the dark mass problem is resolved, it's a bit tough to develop models for how galaxies were created.

 

There's nothing wrong in science with saying "we don't know". You appear to be of the mindset that "we don't know" means "wrong". That's wrong. "We don't know" means (1) scientists don't know (so stop asking), and (2) scientists would love to find out. Scientists love those "we don't know" problems. It's their bread and butter.

 

 

Please also be aware that t is also a rotational black hole. Its high rotational movement creates the famous bar shape as well as the spiral arms. Therefore, all the stars in the spiral arms actually follow the spin power which is generated by the black hole – and not vice versa.

Hence, the Idea that angular momentum could generate this kind of momentum in the black hole is not so logical.

 

Nonsense. The rotation of the central black hole is not responsible for the bar in barred spiral galaxies. You started with a falsehood, then made a conjecture that does not follow from that falsehood, and then compounded these errors by coming up with more nonsense.

 

Here's some science on barred spiral galaxies: R. G. Abraham et al., 1999, The evolution of barred spiral galaxies in the Hubble Deep Fields North and South, MNRAS 308:2 569-576. Arxiv preprint: http://arxiv.org/abs/astro-ph/9811476.

 

Therefore, currently, the science has no solid theory for spiral galaxy formation.

Nonsense.

 

The atom creation Theory is the ultimate answer for what we see in space!!!

This is even more nonsense, and it is also a hijack of your own thread. Please post your nonsense in the appropriate forum.

[David Levy]

Hi D M

In one hand you claim that there is no logic in my message. But in the other hand you gave some thought to this reply and you didn't even eliminate it.

Therefore, I want to thank you…

I hope that you are still ready for some more none logical updates…

[ACG52]

This belongs in Speculations, not in a mainstream science thread.

[David Levy]

Dear Friends

It seems that your logical limits starts and ends at the border of the mainstream concept.

There is no logical way for you to look behind this mainstream black box.

You claim that you would love to find the answer to the issues which you don't know:

""We don't know" means (1) scientists don't know (so stop asking), and (2) scientists would love to find out. Scientists love those "we don't know" problems. It's their bread and butter."

 

But, in reality, your "bread and butter" main concern is protecting the mainstream concept.

Hence, the science can't tolerate any attempt to look behind the mainstream black box borders.

My message is very clear and logical. I show you the way for the living water…But you don't even consider it.

Unfortunately, the science rejects any message which might negatively effects the mainstream concept.

Therefore, the science will continue to look for answers at this mainstream black box, but without any success!!!

One day you will have to open your Eyes!!!

On that day, you might ask my forgiveness!!!

 

Good Luck!

Edited July 3, 2013 by David Levy

[D H]

This belongs in Speculations, not in a mainstream science thread.

I suspected a crackpot setup from the onset. Since he won't say what he's ranting about, this doesn't even belong in Speculations. This belongs in the Circular File forum.

[imatfaal]

!

Moderator Note

 

David Levy

 

Please stop criticising other posters and negatively characterising their mental faculties. You have put forward some ideas - they have been refuted; the situation stands that you either continue to argue your point with evidence, or you concede the failure of your ideas. Do not move to questioning the ability of other members to accept new ideas and painting them as dogmatic. Do not respond to this moderation - if you feel it is unjust report the post.

 

[Airbrush]

"....More recent theories include the clustering of dark matter halos in the bottom-up process. Essentially early on in the universe galaxies were composed mostly of gas and dark matter, and thus, there were fewer stars. As a galaxy gained mass (by accreting smaller galaxies) the dark matter stays mostly on the outer parts of the galaxy. This is because the dark matter can only interact gravitationally, and thus will not dissipate. The gas, however, can quickly contract, and as it does so it rotates faster, until the final result is a very thin, very rapidly rotating disk...."

 

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

 

It seems that spiral galaxies formed very early in the universe. Then collisions between spiral galaxies created the larger eliptical galaxies. I think supermassive black holes fomed long before any stars formed, shortly after the big bang when enough matter was close enough together that such large black holes could form and combine with other large black holes.

[David Levy]

Dear Airbrush

 

Thanks for your message.

Airbrush: "It seems that spiral galaxies formed very early in the universe."

Why??? Why there is no more new spiral galaxy forming process???

Airbrush: " The gas, however, can quickly contract, and as it does so it rotates faster, until the final result is a very thin, very rapidly rotating disk...."

In order for understanding how difficult it is to form a spiral galaxy, let's look at a very simple system:

The Earth and the moon.

As we all know the moon orbits around the Earth. The gravity force is based on the size and distance between those to objects in space.

Let's try to verify what could be the outcome of the distance between the Earth and the moon if the moon will change its rotation velocity???

Assuming that the moon will slow down – It's quite clear that the gravity will force it to come closer and eventually it will collide with Earth.

If the moon will increase its velocity, it will drift further from the Earth and eventually it will escape to space.

Hence, in order to maintain the orbit cycle, there must be a very critical balance between the gravity force and the rotation velocity.

Therefore, the Idea that an object can increase it's velocity and keep its orbit track is none realistic!!!

Now let's think about any gas or stars which started to spin around the supper massive black hole:

In order for setting an orbit track, there must be some sort of gravity force with the supper massive black hole.

If its far away - The gravity force between the supermassive black hole and the star which is located at the far end of the spiral galaxy is almost zero. (As the distance is about 50,000 light years). Actually even the solar system is located far away from the black hole (Hence, no real gravity force). Therefore, assuming that it started to spin before setting the spiral arm, it will surly escape into space.

If it's close enough to have some sort of gravity force, than, it might collide with the black hole before gaining any spin velocity.

Therefore, the current concept of the spiral galaxy forming process must be wrong.

Edited July 3, 2013 by David Levy

[ACG52]

All that post has accomplished is to demonstrate that you don't know anything about orbital mechanics or gravity. You make assumptions based on your ignorance coupled with your own ideas and proclaim them to be fact.

 

There are stars in stable orbits around the supermassive BH in the Milky Way as close as 15 light hours. That's the distance from the sun to Pluto.

 

Furthermore, objects in a lower orbit move faster than objects orbiting further out. The orbital velocity of Venus is 47.9 km/s while the orbital velocity of earth is 29.7 km/s. This is the exact opposite of your assumptions.

Edited July 3, 2013 by ACG52

[David Levy]

Hello ACG52

ACG52: " All that post has accomplished is to demonstrate that you don't know anything about orbital mechanics or gravity. You make assumptions based on your ignorance coupled with your own ideas and proclaim them to be fact. There are stars in stable orbits around the supermassive BH in the Milky Way as close as 15 light hours."

Why you do not read carefully my message??? Why your understanding is so limited??? This has nothing with the mainstream concept. It seems that you are still locked in the same black box!!!

Why can't you understand the following simple message: " Hence, in order to maintain the orbit cycle, there must be a very critical balance between the gravity force and the rotation velocity."

ACG52: " This is the exact opposite of your assumptions."

Why???

Try to read it again and let me know which kind of help do you need.

With pleasure!!!

[D H]

It seems that spiral galaxies formed very early in the universe. Then collisions between spiral galaxies created the larger eliptical galaxies. I think supermassive black holes fomed long before any stars formed, shortly after the big bang when enough matter was close enough together that such large black holes could form and combine with other large black holes.

That wikipedia article that you referenced is exemplary of the problems with wikipedia. It is misleading at best. Right now, theory does not agree with reality. If spiral galaxies formed early but collisions led to elliptical galaxies we should see more spiral galaxies in the Hubble Deep Field than we see now. That's exactly the opposite of what we do see. Galaxy formation is still a challenge.

 

That does not mean we should throw out everything for some nonsense non-theory that explains nothing. It means, hmmm, that's funny. Those two words are music to a scientist's ears.

 

 

In order for understanding how difficult it is to form a spiral galaxy, let's look at a very simple system: The Earth and the moon.

As we all know the moon orbits around the Earth. The gravity force is based on the size and distance between those to objects in space. Let's try to verify what could be the outcome of the distance between the Earth and the moon if the moon will change its rotation velocity??? Assuming that the moon will slow down – It's quite clear that the gravity will force it to come closer and eventually it will collide with Earth. If the moon will increase its velocity, it will drift further from the Earth and eventually it will escape to space. Hence, in order to maintain the orbit cycle, there must be a very critical balance between the gravity force and the rotation velocity.

 

Therefore, the Idea that an object can increase it's velocity and keep its orbit track is none realistic!!!

Go back to square one, David. What you wrote is completely wrong. You apparently don't even understand the two body problem, let alone galaxies.

[David Levy]

Hello D M

 

D M: "Go back to square one, David. What you wrote is completely wrong. You apparently don't even understand the two body problem, let alone galaxies"

 

You just say that I'm wrong. But you can't give even one issue which supports your message.

So let me reuse your message: Please go back to square one!

Please try to be more specific.

After getting your reply, I start to appreciate the message from ACG52. At least he tried to find something… foolish, but something…

[ACG52]

 

 

This has nothing with the mainstream concept.

By which you mean that what you are writing contradicts all actual observation and physics.

 

 

 

Why can't you understand the following simple message: " Hence, in order to maintain the orbit cycle, there must be a very critical balance between the gravity force and the rotation velocity."

I'll assume you mean orbital velocity, not rotation velocity, which has no effect on orbits.

 

 

Why???

Try to read it again and let me know which kind of help do you need.

You explicitly stated that as an orbiting body moves away from it's orbital center it moves faster. That's completely wrong. The help you need is a bsic class on physics and orbital dynamics.

 

And learn how to use the quote function, or is that too mainstream for you?

Edited July 3, 2013 by ACG52

[D H]

Hello D M

 

Learn to use the quote button, and sans that learn to use my correct user name.

 

You just say that I'm wrong. But you can't give even one issue which supports your message.

So let me reuse your message: Please go back to square one!

Please try to be more specific.

Okay. I'll be more specific.

 

 

Assuming that the moon will slow down – It's quite clear that the gravity will force it to come closer and eventually it will collide with Earth.

Nonsense.

 

If the moon will increase its velocity, it will drift further from the Earth and eventually it will escape to space.

Nonsense.

 

Hence, in order to maintain the orbit cycle, there must be a very critical balance between the gravity force and the rotation velocity.

Nonsense.

 

Therefore, the Idea that an object can increase it's velocity and keep its orbit track is none realistic!!!

Huh?

 

 

That probably wasn't specific enough for you. I'll be very specific. Suppose every last joule of energy consumed by humanity was somehow diverted to changing the Moon's velocity. How long would it take to:

• Change the Moon's average orbital velocity by 1%?
• Make the Moon collide with the Earth?
• Make the Moon escape Earth orbit?

Edited July 3, 2013 by D H

[David Levy]

Hello ACG52

ACG52: " You explicitly stated that as an orbiting body moves away from it's orbital center it moves faster."

Really??? I have never used this kind of nonsense. Where did you find it? You have to apologize!

ACG52: "I'll assume you mean orbital velocity, not rotation velocity, which has no effect on orbits."

Yes, sure. Thanks. It seems that you have the ability to understand my message if you wish…

ACG52: " By which you mean that what you are writing contradicts all actual observation and physics."

In my threads I have never contradicted any actual observation or physics. The main issue is that the science is doing whatever it takes to fit those observations into the mainstream black box. Unfortunately for the mainstream concept, it doesn't fit. There are so many problems in this process that the outcome of the science is – "We don't know!!!".

Therefore, the science came with so many supportive theories, but it still doesn't fit!!!

I try to show you that the answer stays just at the edge of our nose. If you just raise your eyes above the mainstream concept you could see the answer. So clear and easy!

I personally appreciate your knowledge is science. It's clear that you are an expert!!! Unfortunately, you are locked by the mainstream concept. Please try to look behind the black box border and you will get to the same conclusions as I did.

[ACG52]

 

ACG52: " You explicitly stated that as an orbiting body moves away from it's orbital center it moves faster."

Really??? I have never used this kind of nonsense. Where did you find it? You have to apologize!

 

That's exactly what this says.

 

 

Let's try to verify what could be the outcome of the distance between the Earth and the moon if the moon will change its rotation velocity???

Assuming that the moon will slow down – It's quite clear that the gravity will force it to come closer and eventually it will collide with Earth.

If the moon will increase its velocity, it will drift further from the Earth and eventually it will escape to space.

Hence, in order to maintain the orbit cycle, there must be a very critical balance between the gravity force and the rotation velocity.

 

 

 

In my threads I have never contradicted any actual observation or physics

The only way you can say this is because you don't know physics and have no clue as to what actual observations are. Just about EVERYTHING you post contradicts real physics.

 

 

 

The main issue is that the science is doing whatever it takes to fit those observations into the mainstream black box. Unfortunately for the mainstream concept, it doesn't fit.

This simply further demonstrates that you don't know any physics. So you resort to making crap up and calling it 'out of the box'.

[David Levy]

Hi D M & ACG52

As you don't agree with the following statement: "Assuming that the moon will slow down – It's quite clear that the gravity will force it to come closer and eventually it will collide with Earth."

Let's see the following info By Wiki: "The Moon completes its orbit around the Earth in approximately 27.5 days (a sidereal month)….With a mean orbital velocity of 1,023 m/s."

Hence, assuming that the orbital velocity decreases suddenly to 100 m/s, what would be the outcome based on your deep knoladge??? Do you need further help???

[D H]

Come off it. A 99% reduction in the Moon's kinetic energy is not representative of your "very critical balance between the gravity force and the rotation velocity." That energy change, by the way, would take humanity about 69 million years to accomplish if every single joule of our current energy consumption was applied to making that change.

 

What outcome would you expect if the Moon's orbital velocity suddenly decreased to 200 meters/second? That's still a 96% reduction in kinetic energy. 150 meters/second? What exactly constitutes a critical balance in your mind?