The Pleiades Star Cluster (APOD 20 Jun 1995)

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harry
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The Pleiades Star Cluster (APOD 20 Jun 1995)

Post by harry » Mon Jul 28, 2008 5:32 am

G'day from the land of ozzz

The Pleiades Star Cluster June 20, 1995

Sorry for going back in time.

http://antwrp.gsfc.nasa.gov/apod/ap950620.html
Explanation: The Pleiades star cluster, M45, is one of the brightest star clusters visible in the northern hemisphere. It consists of many bright, hot stars that were all formed at the same time within a large cloud of interstellar dust and gas. The blue haze that accompanies them is due to very fine dust which still remains and preferentially reflects the blue light from the stars.
Its amazing to find that these stars formed at the same time.

How could this be so?
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Re: The Pleiades Star Cluster June 20, 1995

Post by neufer » Mon Jul 28, 2008 1:57 pm

harry wrote:Its amazing to find that these stars formed at the same time.
How could this be so?

Open (Galactic) Cluster stars are generally all born at the same time with the left over gases quickly being blown away by the new stars (so that the gas can't develop later into younger siblings). This litter of same age but different sized stars start out stretched along the main sequence line but then constantly evolves with the largest (most luminous) stars evolving the fastest.

NGC 2362 is a young un-evolved open star cluster;
whereas, M67 is an old highly evolved open star cluster
of same age but different sized stars:
Image
Last edited by neufer on Thu Jul 31, 2008 9:13 am, edited 3 times in total.
Art Neuendorffer

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Re: The Pleiades Star Cluster June 20, 1995

Post by Chris Peterson » Mon Jul 28, 2008 1:57 pm

harry wrote:G'day from the land of ozzz

The Pleiades Star Cluster June 20, 1995

Its amazing to find that these stars formed at the same time.

How could this be so?
It is actually normal and expected. Groups of stars (sometimes quite large) form together, in regions where the conditions are right. Eventually, the dust and gas is consumed in star formation and the remaining material dissipates. The Pleiades are so new that some of the nebular material is still present. In general, where you have regions containing new stars, they were formed together.
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Post by harry » Tue Jul 29, 2008 2:44 am

G'day from the land of ozz

Just a thought!!!!!

There are varies theories to the formation of stars and star clusters.

One theory is via ejection of compact matter from Black holes. These compact matter act as gravity sinks where solar envelopes form on.
Evolution of galaxies is dependent on the size and activity of the black hole.
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Post by Chris Peterson » Tue Jul 29, 2008 3:27 am

harry wrote:G'day from the land of ozz

Just a thought!!!!!

There are varies theories to the formation of stars and star clusters.

One theory is via ejection of compact matter from Black holes. These compact matter act as gravity sinks where solar envelopes form on.
Evolution of galaxies is dependent on the size and activity of the black hole.
I don't know where that "theory" came from, but I don't think you'll find many people taking it seriously. Stellar formation is reasonably well understood, at least in its broader points. Dust and gas (largely the product of one or more supernovas) coalesce due to self gravitation. Denser regions form, either from supernova shockwaves, collisions between nebulas, or tidal forces. These areas produce rapid condensation leading to star formation. We can see this going on in many places in our region of the galaxy, and also in other galaxies. No need to bring black holes into the discussion, or some mysterious "compact matter", whatever that might be.
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Post by harry » Tue Jul 29, 2008 4:44 am

G'day from the land of ozzzzzz

Its not a fantasy theory. I'm fully aware of the standard star formation theories and ssome of the alternative theories.

Do not limit yourself to what you know.
Google for
Compact matter and jet formation
Black holes and jet formation

Evidence that powerful radio jets have a profound influence on the evolution of galaxies
http://arxiv.org/abs/astro-ph/0409687
Authors: S. Rawlings, M. J. Jarvis
(Submitted on 28 Sep 2004)
Abstract: The relationships between supermassive black holes and the properties of their associated dark-matter halos imply that outflows from accreting black holes provide a feedback mechanism regulating galaxy formation. Accreting black holes with weak or undetectable radio jets (radio-quiet quasars) outnumber those with powerful jets (radio-loud quasars) by a factor ~10-100, so powerful-jet outflows are often neglected. However, whenever powerful jets are triggered, there is a dramatic (factor >100) step-function increase in the efficiency of feedback. We use a feedback model, together with the measured space density of flat-spectrum radio-loud quasars, to show that a powerful-jet episode probably occurred in every protocluster in the Universe. Before jet triggering, there was time for gravitational collapse to create many (~10-100) surrounding protogalaxies massive enough to host radio-quiet quasars. After triggering, the powerful jet pushes back and heats ionized gas so that it cannot fall onto these protogalaxies and cool. Once neutral/molecular gas reservoirs become exhausted, there is a synchronized shut down in both star-formation and black-hole activity throughout the protocluster. These considerations imply that radio-loud quasars have a profound influence on the evolution of all the galaxies seen in clusters today.

Using SKA to observe relativistic jets from X-ray binary systems
http://arxiv.org/abs/astro-ph/0409464
Authors: R. Fender (Amsterdam)
(Submitted on 20 Sep 2004)
Abstract: I briefly outline our current observational understanding of the relativistic jets observed from X-ray binary systems, and how their study may shed light on analogous phenomena in Active Galactic Nuclei and Gamma Ray Bursts. How SKA may impact on this field is sketched, including the routine tracking of relativistic ejections to large distances from the binaries, detecting and monitoring the radio counterparts to 'quiescent' black holes, and detecting the radio counterparts of the brightest X-ray binaries throughout the Local Group of galaxies.
At this moment I'm just learning how it works. It will take me a few more years to understand just a bit more.
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Post by Chris Peterson » Tue Jul 29, 2008 5:08 am

harry wrote:Its not a fantasy theory. I'm fully aware of the standard star formation theories and ssome of the alternative theories.

Do not limit yourself to what you know.
Google for
Compact matter and jet formation
Black holes and jet formation
Okay. I find very little. I would interpret "compact matter" to be the material making up neutron stars and black holes. Nothing in the papers you reference (or that I find with Google) makes any suggestion this (or any other) "compact matter" is ejected from black holes. Neither do your references in any way discuss stellar formation, or star cluster formation. The papers propose mechanisms whereby jets from the supermassive black holes in the center of protogalaxies may have influenced the evolution of galaxies and galaxy clusters. All very interesting, but nothing to do with the subject you seem to be relating them to.
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Post by harry » Thu Jul 31, 2008 2:20 am

G'day Chris

You can sit on the fence and wait for the info or you can research the information.

From your words it seems that you know very little of Neutron stars and compacted matter and Black holes.

So! read up on them.
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Post by Doum » Thu Jul 31, 2008 4:44 pm

On the contrary Harry. Giant Black Hole become a stoper of star formation with big galaxy. It seem to forbid it. Look:

http://www.msnbc.msn.com/id/24972045/

Chris is the one who is right. Your theory dont hold at all. It does'nt make sense.

Stop hiding behind the fence and dont go sit on it neither. Instead come over it on the same side we are. :wink:

Continue to smile also. :D

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Post by harry » Fri Aug 01, 2008 1:05 am

Hello Doum

Please use better science links to prove your point.

As for being right or wrong thats another isse.

Trying to understand the workings of compacted matter and the formation of jets, thats a big issue.

We know that most matter that enters the compacted core (BH) degenerates and that jets eject this degenrate matter and in its way will break apart stars, but the good thing is that it will allow stars to reform around gravity sinks. A part in the reforming of galaxies.

If you think that you "KNOW" and you are right than stop learning.
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Post by Chris Peterson » Fri Aug 01, 2008 1:36 am

harry wrote:We know that most matter that enters the compacted core (BH) degenerates and that jets eject this degenrate matter and in its way will break apart stars...
Citations?

Our understanding of jets around black holes is that they are ordinary matter that comes close to the event horizon, but does not fall into the BH. We have no theory to suggest what happens to matter that actually falls into a BH, but we are pretty darn sure it never comes out again.
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Post by harry » Fri Aug 01, 2008 9:37 am

G'day Chris

You said
Our understanding of jets around black holes is that they are ordinary matter that comes close to the event horizon, but does not fall into the BH. We have no theory to suggest what happens to matter that actually falls into a BH, but we are pretty darn sure it never comes out again.
Understanding of Black holes and jets is the issue.

I can leave this and agree that you are right.

That would be a mistake.

Are you willing to read further and learn about the so called theoretical black holes and jets. Or I'm just wasting my time.
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Post by Chris Peterson » Fri Aug 01, 2008 2:27 pm

harry wrote:Are you willing to read further and learn about the so called theoretical black holes and jets. Or I'm just wasting my time.
I consider myself well educated with respect to current theory on black holes and jet formation.

I'm not particularly interested in hearing about theories that haven't been at least minimally vetted through publication in mainstream scientific journals. I'd be eager to read any articles you can reference that propose jets streaming from black holes consist of compact matter, or that they consist of matter that originated inside the event horizon. If I understand you correctly, you are suggesting that both of these are the case.

If you can't provide some academic citations justifying your opinions here, then yes, you would just be wasting your time (and mine) discussing it further.
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Post by harry » Sat Aug 02, 2008 4:20 am

G'day Chris

This part of the Forum does not discuss topics.

Open a new topic in Cafe and we shall tango till the cows come home.

We are all well educated, that does not mean we know jack ,,,,,,,,.
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The Pleiades Star Cluster June 20, 1995

Post by starnut » Sun Aug 03, 2008 12:40 am

harry wrote:G'day Chris

This part of the Forum does not discuss topics.

Open a new topic in Cafe and we shall tango till the cows come home.

We are all well educated, that does not mean we know jack ,,,,,,,,.
:roll: Still as evasive as ever, aren't you, Harry? Why do you still refuse to give more than brief remarks and oodles of links to explain why you believe your assertions to be correct and the published findings of mainstream (read: real) scientists to be wrong? Many of the links you gave don't even support your statements, as Chris has found. If you are as well educated as you say, what about telling us your qualifications, i.e., university degrees and professional society memberships and fellowships?

Disclosure: I have just a bachelor's degree in physics and did not pursue postgraduate degrees due to needs to earn a living, but I retain lifelong interests in science, particularly in astronomy.

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Post by harry » Sun Aug 03, 2008 11:38 pm

G'day starnut

It seems you do not read my comments enough.

Making silly statements does not give a solution.

I have offered to discuss the topic elswhere.

As far as compact matter is concerned it is well covered by just google.

Degenerate matter
Neutron stars
Jet formation and experiments with the Z-pinch relating to astrophysics.

These are just general info.

I'm not here for that.


As far as my personal info. I keep it to my self.
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Post by Doum » Sun Aug 03, 2008 11:42 pm

Just a reminder for all to see what Harry think. So now you will all know with whom you are talking. Dont be mad Harry, now they know what you profoundly beleive. All that is base on a recyling universe. By the way Harry, is your model ready? :twisted:


--------------------------------------------------------------------------------

Quote
"harry
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Posted: Thu Aug 17, 2006 9:22 am Post subject:

--------------------------------------------------------------------------------
In two years time I'll put forward a model that incorporates.

The Big Bang theory
The string
The steady state
The recyclic
The plasma cosmology
The wave
Observations
and so on.

If I knew it was going to be so time consuming I would not have started.
But! now that I have started I cannot stop. "

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Post by harry » Mon Aug 04, 2008 4:33 am

G'day doum

Smile,,,,,,,,,,,not mad,,,,just crazy.

The amount of info is extra ordinary.

I'm reading through papers on

Degenerate matter and black holes
Compact matter and the formation of jets
Redshift
Plasma and the Z-pinch mechanism in the formation of Jets.

At this moment reading through this link
http://adsabs.harvard.edu/cgi-bin/nph-b ... &version=1

The model of a recyclic process is not new to cosmology, there are varies types and some include the theory of the Big Bang.


If you want a model that works, not existing yet.
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Post by Doum » Wed Aug 06, 2008 3:56 pm


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Post by harry » Thu Aug 07, 2008 9:22 am

G'day Doum

I read the link

What ever you feed a computer it will produce what you want.

The complex working parts of our universe have not been understood. So can we we feed the computer information that we do not have.

The only way to do this is to assume that the Big Bang is correct, knowing quite well that the foundations of the BBT are built from ad hoc ideas.

Thats ideas to make the model work.
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Post by Chris Peterson » Thu Aug 07, 2008 2:21 pm

harry wrote:What ever you feed a computer it will produce what you want.
The article in question makes no assumptions about the Big Bang. It describes a computer model that attempts to explain stellar formation in a simple gaseous environment.

Computer models are a powerful method of "experimenting" with things that cannot be repeated in a lab. Done properly, the model emulates only known physical laws, and produces a result matching actual observation. When that happens, it provides evidence (but never proof) that your initial conditions match reality.
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Post by starnut » Fri Aug 08, 2008 1:21 am

harry wrote:G'day Doum

I read the link

What ever you feed a computer it will produce what you want.

The complex working parts of our universe have not been understood. So can we we feed the computer information that we do not have.

The only way to do this is to assume that the Big Bang is correct, knowing quite well that the foundations of the BBT are built from ad hoc ideas.

Thats ideas to make the model work.
Harry,

You seem to doubt, if not outrightly reject, everything mainstream scientists reported. Why? What is your agenda?

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Post by harry » Fri Aug 08, 2008 2:33 am

Hello Starnut


My agenda is trying to learn and understand.

I'm reading upto date papers in varies subjects and they are maintream.

Somehow main stream is not links that do not rely on science.

I will be back

Got to go
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