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Is the Sun a binary?
- Joe Keller
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16 years 4 months ago #20218
by Joe Keller
Replied by Joe Keller on topic Reply from
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">["Nemesis", previous page] This leaves an object that is massive but emits very little electromagnetic radiation.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Dr. Van Flandern response: That is rather contradictory. Massive implies hot, and hot implies radiating abundantly.
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">["Nemesis"] Possible candidates could be a brown dwarf, or a collapsed object like a neutron star, a supernova remnant. I favor the latter possibility myself.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Dr. TVF: Doesn't that require that the Sun had a companion that went supernova? That would have wiped out the planets and changed the Sun drastically from a normal G-type star.
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">["Nemesis"] The best way to detect it may be through occultation of background stars. This latter method may be the only way to pick up a collapsed object, or maybe gravitational lensing of background objects.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Dr. TVF: The gravitational lensing should indeed be strong and evident. But the whole sky has been surveyed many times, which is how we get proper motions of stars. And region where gravitational lensing was going on would distort all the proper motions in that vicinity. No such region has been seen. So no dark companion with significant gravity exists. (par.) There is now yet another direct test for this, one that I also mentioned to Cruttenden. Pulsar timings allow us to detect any unknown accelerations of the Sun's motion through space, because they would displace the Earth a bit closer to pulsars in some direction, but farther away from pulsars in the opposite direction. So the arrival times of pulsar signals would be changed by a certain predictable pattern across the sky. This has long been known as a test for the possible existence of undiscovered planets of significant mass. No such displacement signal is seen, meaning the Sun is not undergoing any significant acceleration from an unknown cause. -|Tom|-
Joe Keller's comment:
A more detailed version of the following information, was posted piecemeal, subsequent to the above 2006 post by Dr. Van Flandern, by me on the "Requiem for Relativity" thread.
The last statement, about pulsar timing, especially refers to the Oct. 2005 article of Zakamska & Tremaine of Princeton, which to my knowledge has not been superseded in accuracy. They claimed only the ability to detect a Jupiter at 200 AU (or a solar mass at 200*sqrt(1000)=6000AU=0.1 light year). These authors mixed nonparametric and parametric statistics, which might have caused them to overestimate the sensitivity of their test. Also, my own investigation has revealed that millisecond pulsars (commonly a kiloparsec distant, and who knows what is really happening in the vast intervening space?) show a median Pdot/P which happens to equal the Hubble constant. This peculiar and unexplained coincidence of Pdot/P with the so-called "Hubble expansion", casts doubt on the simple model of acceleration which underlies Zakamska and Tremaine's conclusion.
Regarding gravitational lensing, Gaudi & Bloom, Astrophysical Journal 635:711+, Dec. 2005, state in their abstract:
"...Gaia (launch date 2011). A Jupiter-mass object at 2000 AU is detectable by Gaia over the whole sky above 5 sigma, with even stronger constraints if it lies near the ecliptic plane. ..."
Until now I've omitted microlensing from my Barbarossa discussion, because I saw this article. Here is a claim that sometime after 2011, a planned satellite better than Hipparcos *will be* able to detect a Jupiter at 2000AU. Surely Gaia will exceed Hipparcos not only in accuracy but in the number of stars observed; and Hipparcos exceeded ground-based astrometry in accuracy. I haven't yet found any article claiming that Hipparcos has ruled out a companion of any mass at any distance in any part of the sky (if anyone knows of one, please tell me!).
Good point about the supernova remnant, Dr. Van Flandern!
Regarding mass and temperature, the state of the art (1990s) calculation in the mainstream literature, is that a 4.6 billion yr old brown dwarf is roughly the same temperature whether it is slightly above or slightly below the critical mass for (brief) nuclear reaction ignition. The present temperature of the brown dwarf is very sensitive to the (very small) theoretical thermal conductivity of the degenerate matter. However, in 4.6 billion years, there's a lot that can go wrong with a theoretical model of bulk physical properties, untestable in the lab. Unexpected mechanisms of convection might occur; or, gravitational energy might be deposited mainly on the surface, not the interior, to begin with, depending on the mechanism of accretion.
Dr. Van Flandern, I'd like to work for Mr. Cruttenden!
Dr. Van Flandern response: That is rather contradictory. Massive implies hot, and hot implies radiating abundantly.
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">["Nemesis"] Possible candidates could be a brown dwarf, or a collapsed object like a neutron star, a supernova remnant. I favor the latter possibility myself.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Dr. TVF: Doesn't that require that the Sun had a companion that went supernova? That would have wiped out the planets and changed the Sun drastically from a normal G-type star.
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">["Nemesis"] The best way to detect it may be through occultation of background stars. This latter method may be the only way to pick up a collapsed object, or maybe gravitational lensing of background objects.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Dr. TVF: The gravitational lensing should indeed be strong and evident. But the whole sky has been surveyed many times, which is how we get proper motions of stars. And region where gravitational lensing was going on would distort all the proper motions in that vicinity. No such region has been seen. So no dark companion with significant gravity exists. (par.) There is now yet another direct test for this, one that I also mentioned to Cruttenden. Pulsar timings allow us to detect any unknown accelerations of the Sun's motion through space, because they would displace the Earth a bit closer to pulsars in some direction, but farther away from pulsars in the opposite direction. So the arrival times of pulsar signals would be changed by a certain predictable pattern across the sky. This has long been known as a test for the possible existence of undiscovered planets of significant mass. No such displacement signal is seen, meaning the Sun is not undergoing any significant acceleration from an unknown cause. -|Tom|-
Joe Keller's comment:
A more detailed version of the following information, was posted piecemeal, subsequent to the above 2006 post by Dr. Van Flandern, by me on the "Requiem for Relativity" thread.
The last statement, about pulsar timing, especially refers to the Oct. 2005 article of Zakamska & Tremaine of Princeton, which to my knowledge has not been superseded in accuracy. They claimed only the ability to detect a Jupiter at 200 AU (or a solar mass at 200*sqrt(1000)=6000AU=0.1 light year). These authors mixed nonparametric and parametric statistics, which might have caused them to overestimate the sensitivity of their test. Also, my own investigation has revealed that millisecond pulsars (commonly a kiloparsec distant, and who knows what is really happening in the vast intervening space?) show a median Pdot/P which happens to equal the Hubble constant. This peculiar and unexplained coincidence of Pdot/P with the so-called "Hubble expansion", casts doubt on the simple model of acceleration which underlies Zakamska and Tremaine's conclusion.
Regarding gravitational lensing, Gaudi & Bloom, Astrophysical Journal 635:711+, Dec. 2005, state in their abstract:
"...Gaia (launch date 2011). A Jupiter-mass object at 2000 AU is detectable by Gaia over the whole sky above 5 sigma, with even stronger constraints if it lies near the ecliptic plane. ..."
Until now I've omitted microlensing from my Barbarossa discussion, because I saw this article. Here is a claim that sometime after 2011, a planned satellite better than Hipparcos *will be* able to detect a Jupiter at 2000AU. Surely Gaia will exceed Hipparcos not only in accuracy but in the number of stars observed; and Hipparcos exceeded ground-based astrometry in accuracy. I haven't yet found any article claiming that Hipparcos has ruled out a companion of any mass at any distance in any part of the sky (if anyone knows of one, please tell me!).
Good point about the supernova remnant, Dr. Van Flandern!
Regarding mass and temperature, the state of the art (1990s) calculation in the mainstream literature, is that a 4.6 billion yr old brown dwarf is roughly the same temperature whether it is slightly above or slightly below the critical mass for (brief) nuclear reaction ignition. The present temperature of the brown dwarf is very sensitive to the (very small) theoretical thermal conductivity of the degenerate matter. However, in 4.6 billion years, there's a lot that can go wrong with a theoretical model of bulk physical properties, untestable in the lab. Unexpected mechanisms of convection might occur; or, gravitational energy might be deposited mainly on the surface, not the interior, to begin with, depending on the mechanism of accretion.
Dr. Van Flandern, I'd like to work for Mr. Cruttenden!
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16 years 3 months ago #20383
by Pluto
Replied by Pluto on topic Reply from
G'day from the land of ozzzzzzzz
I'd like an opinion on Prof Oliver Manuels work on the Origin of our solar system.
www.omatumr.com/PapersArxiv.html
arxiv.org/abs/astro-ph/0510001
Isotopes Tell Origin and Operation of the Sun
The Origin, Composition, and Energy Source for the Sun
arxiv.org/abs/astro-ph/0411255
Why the Model of a Hydrogen-Filled Sun Is Obsolete
arxiv.org/abs/astro-ph/0410569
Prof Oliver has brought up some interesting scientific issues on the origin of our solar system.
Smile and live another day
I'd like an opinion on Prof Oliver Manuels work on the Origin of our solar system.
www.omatumr.com/PapersArxiv.html
arxiv.org/abs/astro-ph/0510001
Isotopes Tell Origin and Operation of the Sun
The Origin, Composition, and Energy Source for the Sun
arxiv.org/abs/astro-ph/0411255
Why the Model of a Hydrogen-Filled Sun Is Obsolete
arxiv.org/abs/astro-ph/0410569
Prof Oliver has brought up some interesting scientific issues on the origin of our solar system.
Smile and live another day
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16 years 3 months ago #20137
by tvanflandern
Replied by tvanflandern on topic Reply from Tom Van Flandern
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Pluto</i>
<br />I'd like an opinion on Prof Oliver Manuels work on the Origin of our solar system.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">If you want discussion here, present the information you wish to discuss here. Don't force people to go to other web sites.
In general, Oliver's stuff is well-thought-out and documented. We featured one of his articles about the Sun in the Meta Research Bulletin a few years back. And he may be planning to attend the coming cosmology conference (CCC2) in Port Angeles, where he is listed as a co-author on a presentation. -|Tom|-
<br />I'd like an opinion on Prof Oliver Manuels work on the Origin of our solar system.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">If you want discussion here, present the information you wish to discuss here. Don't force people to go to other web sites.
In general, Oliver's stuff is well-thought-out and documented. We featured one of his articles about the Sun in the Meta Research Bulletin a few years back. And he may be planning to attend the coming cosmology conference (CCC2) in Port Angeles, where he is listed as a co-author on a presentation. -|Tom|-
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16 years 3 months ago #15372
by Pluto
Replied by Pluto on topic Reply from
G'day from the land of ozzzzz
Hello tvanflandern
I agree with you in reference to Prof Olivers work.
Lets pick one topic
The Origin, Composition, and Energy Source for the Sun
arxiv.org/abs/astro-ph/0411255
The Origin, Composition, and Energy Source for the Sun
Authors: O. Manuel, C. Bolon, M. Zhong, P. Jangam
(Submitted on 10 Nov 2004)
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Abstract: Heterogeneous supernova debris formed the solar system. Cores of inner planets formed in the central iron rich region. The Sun formed on the collapsed supernova core. Lighter elements and the lighter isotopes of each element are enriched at the solar surface. The most abundant nuclide in the Sun is Iron 56, the decay product of doubly magic Nickel 56. Doubly magic Oxygen 16 is next most abundant. The least abundant elements, Li, Be, and B, have loosely bound nucleons. Abundance is linked with nuclear stability, except for an over abundance of H from neutron emission and neutron decay near the core. The main elements in the Sun, Fe, Ni, O, Si, S, Mg, and Ca, comprise 99 percent of meteorites. Neutron emission from the SN core triggers a series of reactions that produce solar luminosity, solar neutrinos, excess H, and an annual outpouring of 2.7 E 43 Hydrogen atoms in the solar wind. <hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
I have noticed that many critics read the info out of context and assume that the sun has an Iron core.
Smile and live another day
Hello tvanflandern
I agree with you in reference to Prof Olivers work.
Lets pick one topic
The Origin, Composition, and Energy Source for the Sun
arxiv.org/abs/astro-ph/0411255
The Origin, Composition, and Energy Source for the Sun
Authors: O. Manuel, C. Bolon, M. Zhong, P. Jangam
(Submitted on 10 Nov 2004)
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Abstract: Heterogeneous supernova debris formed the solar system. Cores of inner planets formed in the central iron rich region. The Sun formed on the collapsed supernova core. Lighter elements and the lighter isotopes of each element are enriched at the solar surface. The most abundant nuclide in the Sun is Iron 56, the decay product of doubly magic Nickel 56. Doubly magic Oxygen 16 is next most abundant. The least abundant elements, Li, Be, and B, have loosely bound nucleons. Abundance is linked with nuclear stability, except for an over abundance of H from neutron emission and neutron decay near the core. The main elements in the Sun, Fe, Ni, O, Si, S, Mg, and Ca, comprise 99 percent of meteorites. Neutron emission from the SN core triggers a series of reactions that produce solar luminosity, solar neutrinos, excess H, and an annual outpouring of 2.7 E 43 Hydrogen atoms in the solar wind. <hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
I have noticed that many critics read the info out of context and assume that the sun has an Iron core.
Smile and live another day
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16 years 3 months ago #20937
by tvanflandern
Replied by tvanflandern on topic Reply from Tom Van Flandern
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Pluto</i>
<br />from Oliver Manuel<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">The main elements in the Sun, Fe, Ni, O, Si, S, Mg, and Ca, comprise 99 percent of meteorites.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote"><hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">The only reason the light elements are not abundant in meteorites is that they do not have sufficient gravity to hold them. The lighter the element, the faster is its average molecular speed. And those speeds for most light elements are in excess of escape velocity from small bodies. Only the gas giant planets have enough gravity to retain hydrogen, the lightest element. And as expected, those planets do contain abundant hydrogen.
So while Manuel may be right that the role of heavy elements in the Sun has been underestimated, it does not seem reasonable to me to suggest that the light elements have such a minor role -- especially if meteorites are used to suggest a standard of comparison. -|Tom|-
<br />from Oliver Manuel<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">The main elements in the Sun, Fe, Ni, O, Si, S, Mg, and Ca, comprise 99 percent of meteorites.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote"><hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">The only reason the light elements are not abundant in meteorites is that they do not have sufficient gravity to hold them. The lighter the element, the faster is its average molecular speed. And those speeds for most light elements are in excess of escape velocity from small bodies. Only the gas giant planets have enough gravity to retain hydrogen, the lightest element. And as expected, those planets do contain abundant hydrogen.
So while Manuel may be right that the role of heavy elements in the Sun has been underestimated, it does not seem reasonable to me to suggest that the light elements have such a minor role -- especially if meteorites are used to suggest a standard of comparison. -|Tom|-
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16 years 3 months ago #20138
by Jim
Replied by Jim on topic Reply from
If heavy elements are made in SN events would those elements be found in meteors that came from a source other than a SN? You say meteors exist but not where they came from.
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