Sagittarius Triplet (APOD 14Jun06)

orin stepanek · Post by **orin stepanek** » Thu Jun 15, 2006 12:20 am

http://antwrp.gsfc.nasa.gov/apod/ap060614.html

An awesome sight. My question is this; how dense is the gas and dust that make up the clouds surrounding the triplet? If a space traveler were going through would he be aware of the cosmic dust and gas surrounding him?

Orin

harry · Post by **harry** » Thu Jun 15, 2006 5:05 am

hello Orin

This may help

http://www.aao.gov.au/images/general/emission.html

and yes it is a fantastic image.

Makes me want to build a rocket. Missing the starter motor.

and more nebula
http://www.spacetelescope.org/images/ar ... c/nebula//

Qev · Post by **Qev** » Thu Jun 15, 2006 5:56 am

A molecular gas cloud is considered 'dense' if it has a particle density higher than 100 particles per cubic centimeter. At sea level, Earth's atmosphere has roughly 10^18 particles per cubic centimeter. So even a 'very dense' molecular cloud is tenuous at best, compared to what humans are used to.

orin stepanek · Post by **orin stepanek** » Thu Jun 15, 2006 3:03 pm

Thanks Qev; but how can this be measured? Most of these actually block out starlight from behind them. Nice link Harry.
Orin

harry · Post by **harry** » Fri Jun 16, 2006 12:39 pm

Hello All

In these images you can even see the dust and matter.

NGC 7293: The Helix Nebula
http://antwrp.gsfc.nasa.gov/apod/ap960417.html

Cometary Knots in the Helix Nebula
http://antwrp.gsfc.nasa.gov/apod/ap960416.html

At the Edge of the Helix
http://antwrp.gsfc.nasa.gov/apod/ap960422.html

------------------------------------------------------------------------------
I want to build a rocket and go where no man has gone before and trek across space.

That is how I feel every time I see images.

Qev · Post by **Qev** » Fri Jun 16, 2006 8:58 pm

orin stepanek wrote:Thanks Qev; but how can this be measured? Most of these actually block out starlight from behind them. Nice link Harry.
Orin

Honestly I'm not certain how the density of such clouds is measured. If I had to guess, I'd say probably by how transparent the clouds are to various wavelengths of light (including infrared and radio).

The clouds may be very diffuse from our point of view, but bear in mind that they are several light-years across: even at 100 particles per cubic centimeter, that adds up to a lot of gas.

randall cameron · Post by **randall cameron** » Sat Jun 17, 2006 9:51 am

I don't know either, but I guess they estimate it crudely based on either optical density (how much light gets blocked from objects behind), or by estimating the cloud mass due to its gravitational effect on nearby objects or gravitational lensing of objects behind, and possibly subtracting the mass of identified stars within (easily determined for binaries or from spectral type). Once you have an idea of the mass, average density may be estimated from the (visually) apparent volume.

However, that would be both crudely estimated and an average. Density could vary tremendously from one part of a cloud to another -- higher in star forming regions, lower far from any stars.

orin stepanek · Post by **orin stepanek** » Sun Jun 18, 2006 3:32 am

How can stars form from such rarefied conditions? I would suspect that enough stellar mater would be needed for gravitational attraction to coalesce these gasses into blazing stars. I would suspect these gasses and dust to be of higher particle count. Realizing of course that through the vast voids that a lot of gas would be present even at these rarefied conditions.
Orin

harry · Post by **harry** » Sun Jun 18, 2006 4:09 am

Hello

Star formation in many cases starts the same time the star goes into supernova. The compact core is formed in a very short time and the rest of the matter is sucked back in if not becomes part of the solar system or nebula that shares its matter with other sun cores and rejuvinates them.

See link blok
http://articles.adsabs.harvard.edu//ful ... 3.000.html

http://dsnra.jpl.nasa.gov/origins/nyt.html
http://www-astronomy.mps.ohio-state.edu ... imass.html
http://www-astronomy.mps.ohio-state.edu ... rnova.html
http://cfa-www.harvard.edu/swas/science1.html
http://fire.biol.wwu.edu/trent/alles/Star_Formation.pdf

The above would give you some reading on the density of the dust clouds and the seeding of the stars.

Qev · Post by **Qev** » Sun Jun 18, 2006 7:30 pm

orin stepanek wrote:How can stars form from such rarefied conditions? I would suspect that enough stellar mater would be needed for gravitational attraction to coalesce these gasses into blazing stars. I would suspect these gasses and dust to be of higher particle count. Realizing of course that through the vast voids that a lot of gas would be present even at these rarefied conditions.
Orin

I daresay in actual star-forming areas of these clouds, the densities increase greatly as gravitational attraction pulls the surrounding gases in. The 100 particles/cc number was basically just the line above which most astronomers consider a gas cloud 'dense'; they can obviously be denser than this! But outside of the regions where stars or other bodies are actually forming, the gas density is going to be extremely low compared to Earth's atmosphere.

Regarding star formation itself, supernova explosions enrich the stellar medium with heavier elements, and the shockwaves caused by such explosions can trigger cloud collapse and new stars to form, but no hydrogen-burning star is going to form around a neutron star 'core'. It just can't happen. oO;

harry · Post by **harry** » Mon Jun 19, 2006 4:51 am

Hello Qev

Our sun's origin was a neutron star. I could be wrong.

The point is this it still has a form of degerated matter in the inner core.

As for the Origin of our sun and the solar system

Ther are many links, But ! I like the logic of the following link

see link
http://web.umr.edu/~om/report_to_fcr/report_to_fcr1.htm

The Sun’s radiant energy and protons in the solar wind (SW) come from the collapsed supernova core, a neutron star (NS), on which the Sun formed. The cradle (Figs. 9-12) indicates that the energy of each neutron in the Sun’s central NS exceeds that of a free neutron by @ 10-22 MeV (Figs. 13-15) Solar luminosity and the flux of solar-wind protons are generated by a series of reactions (Fig. 16): a) escape of neutrons from the central NS, b) decay of free neutrons or their capture by other nuclides, c) fusion and upward migration of H+ through material that accreted on the NS, and d) escape of H+ in the SW. An example might be:

a) The escape of neutrons from the NS, <1n> –> 1n + 10-22 MeV

b) The decay of free neutrons, 1n –> 1H+ + e- + nanti + 0.78 MeV

c) Fusion of hydrogen, 4 1H+ + 2 e- –> 4He++ + 2 n + 26.73 MeV

d) Some H+ reaches the surface and departs in the solar wind

Reactions like a) and b) produce part of the Sun’s radiant energy and perhaps the luminosity of isolated neutron stars25. Note that reaction a) alone may release more energy per nucleon than is released by the sum of reactions b) and c), the decay or capture of neutrons plus H-fusion. The well-established Solar Neutrino Puzzle26 confirms that reaction c) generates only part of the Sun’s total luminosity. Most 1H+ from b) is consumed by H-fusion, but the anomalous abundance of H (See Fig.
shows that 1H+ also leaks from the interior, selectively carrying lighter nuclides to the solar surface (See Fig. 6) before departing in the solar wind at an emission rate of about 2.7 x 1043 1H/yr. Homochirality in living creatures26 was likely initiated by circularly polarized light (CPL) from the Sun’s early NS. Their fate and climate changes of planets27 may depend on the half-life of this massive nucleus at the Sun’s core.

Two of the problems of not having a high density core is the control of heat from the core and keeping the sun from expanding out.

Qev · Post by **Qev** » Mon Jun 19, 2006 9:09 pm

While the core of the Sun may be dense, it's not composed of degenerate matter, at least not as far as I'm aware; the radiation pressure produced by fusion counteracts the tendancy to collapse under gravity, and keeps the core density from increasing beyond a certain point. This balancing act also is what maintains the size and structure of the Sun.

The other problem with this theory is that there is no Solar Neutrino Puzzle/Problem anymore. We've accounted for the 'missing' neutrinoes, which shows that the majority of the Sun's power generation comes from fusion energy.

harry · Post by **harry** » Mon Jun 19, 2006 11:31 pm

Hello Qev

Smile,,,,,,,,,,,,,its not as simple as that.

I have given this problem to some high scientists and I hope they come back with some answers.

I don't think that the main energy comes from fusion but! from the Inner core.
For that energy to be released it needs to come from a neutron core or similar, releasing neutrons and in so doing releasing energy during the process.

Smile, mosts scientists do not agree with me.

Thats my thoughts until we get more info.

Qev · Post by **Qev** » Tue Jun 20, 2006 6:18 am

Sorry Harry, I'm just not gonna buy this theory.

An object like what you're describing would have a very hard time forming, if it's even possible for it to form. Any quantity of fusable matter falling onto the surface of a neutron star is going to fuse in very short order. There's no way an amount of hydrogen gas like what makes up the Sun is going to accrete around a neutron star; as mass started to accumulate, runaway fusion occurs across the surface of the neutron star, and blasts the surrounding material away again. It's called a 'burster'.

And again, now that the Solar Neutrino Problem has been more-or-less solved, this theory doesn't account for the now-excessive amount of fusion-produced energy.

I think I'm gonna stick with the old-fashioned core-fusion theory for the time being.

harry · Post by **harry** » Tue Jun 20, 2006 9:56 am

Hello Qev

Smile its not for sale.

You should stick with the flow. 99% of scientists do.

But! if you know me by now,,,,,,,,,,,,I go out on a limb and rock the boat.

If we agreed with all, than we would not have a discussion.
If we were all "yes" men we would not be "no" men or something like that.

Have you read this link

http://web.umr.edu/~om/report_to_fcr/report_to_fcr1.htm

Pete · Post by **Pete** » Tue Jun 20, 2006 1:34 pm

One thing about that theory, Harry, is that neutron stars are more massive than the Sun... Also, just as Qev pointed out, a few neutron stars are observed to be trying to "follow in the Sun's footsteps" in accordance with your theory by accreting matter (from binary companions in most if not all cases), but they just produce X-ray bursters.

By the way, I get a permission denied error for the link you provided: http://web.umr.edu/~om/report_to_fcr/report_to_fcr1.htm

orin stepanek · Post by **orin stepanek** » Wed Jun 21, 2006 12:20 pm

http://web.umr.edu/~om/report_to_fcr/report_to_fcr1.htm

I also get a you are not authorised to use this link.

Orin

harry · Post by **harry** » Fri Jun 23, 2006 4:25 am

Hello Orin

Yes you are right.

Darn, it is nice research on the cutting edge.

Why did they restrict the link.

If you need notes on it I think I have a copy, but! there are graphs and figures and so on that you need to get into the link.

Anyway................I'm surfing the net for more reseach,,,,,,,,,,darn waves are big