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scordova
Joined: 19 Jun 2007
Posts: 321
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 Posted: Sun Aug 19, 2007 11:34 pm Post subject: Evidence for a Small Universe, van Maanen |
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Here is a picture of mysterious rings associated Supernova 1987A. It suggests there is maybe something we don't understand in terms of basic optics of what's happening in space.
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When the Hubble Space Telescope was pointed at the supernova remnant in 1994, however, curious rings were discovered. The origins of these rings still remains a mystery.
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All this to say, I'm not so sure we really know as much as we need to before making certain pronouncements about distance measurements. Anomalies like the above may suggest we may have difficulties in the way we perceive objects at very far distances....
Because the measurement of distance is so critical to theory, I thought it would be good to revisit the issue.
Distance inverse square law seems eminently reasonable, but there are issues with it. First off it assumes:
1. no unaccounted impediments of distant light to ourselves
2 nothing is weakening brightness in addition to the usual weakening with distance
Dr. Cheesman's objection to CDK regarding an inverse quartic (versus square) law might occur has been on the back of my mind. Thus CDK (if true) may suggest objects are much closer than they are. I have vacillated between saying the flux problem is compensated by increasing energy density (Setterfield's explanation) and the hypothesis of a MUCH smaller universe and that our distance and size measurements are totally wrong
The hypothesis of a much smaller universe is in principle testable if the astronomical community is willing to revisit measurements it presumed were a foregone conclusion. They became foregone conclusions as Big Bang cosmology took hold. But perhaps it is now worth revisiting issues that people have long taken for granted as undeniable fact. 
Adriaan van Maanen's Evidence for a Small Universe
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Adriaan van Maanen's monumental work on of spiral nebulae, as it stood in 1921, offers a long overlooked (read "rejected") solution to the flat rotational velocity curves for "galaxies." In the author's opinion, van Maanen's investigations have been wrongfully relegated to oblivion. Evidence will be presented below to hopefully help rectify the situation, and to commend van Maanen's findings as an already-accomplished solution to one half of the missing mass problem.
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And from On Spiral Nebulae, van Maanen et al.
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Jeans J. H., "Note on the Distances and Structure of the Spiral Nebulae," MNRAS, 85, 531-534 (1925) - NADS
Results recently published by Hubble and Shapley seem to establish the inaccuracy of estimates I made some time ago of the distances and other quantities associated with the spiral nebulae. Hubble estimates the distance of M 31 (the Andromeda nebula) as 950,000 light-years, as against my estimate of 5000 light-years.
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Jeans revised his estimate based on the fact Andromeda looked too faint. He reasoned if something looks faint it must be very far away. But as I pointed out, this may not be true. We simply don't know, but if we were to make some measurements of galactic rotation visually, we might have some clue.
If we can monitor if this galaxy rotates and then correlate the doppler velocities (assuming there is sufficient tilt to allow a doppler measurement), we can estimate distance. I pointed out however, this will not exactly accord in CDK since CDK predicts a discord between visual astrometric and spectroscopic doppler measurments. But this would still be a good start to measure the rotation of these "galaxies" astrometrically versus spectroscopically.
See M81 Internal Motions, van Maanen
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Readers are encouraged to see the Hubble Site 07 Feb 2002 release, Hubble Reveals 'Backwards' Spiral Galaxy". Future findings may invalidate the picture but, at present, astronomers suggest that "the galaxy called NGC 4622 appears to be rotating in the opposite direction to what they expected." The apparent direction of rotation is similar to that for van Maanen's measured internal motions for M81 shown above.
[Added 06 August 2003.]
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Last edited by scordova on Sun Sep 09, 2007 11:53 pm; edited 1 time in total |
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scordova
Joined: 19 Jun 2007
Posts: 321
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| Posted: Wed Aug 22, 2007 9:26 am Post subject: |
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Here is something suggesting that objects presumed to be billions of light years away could actually be in our own galaxy.
Proper motion of Quasars
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These three quasars and their respective proper motions (in arcsec/yr) are
PHL 1033 : 0.049±0.013
LB 8956 : 0.061±0.018
LB 8991 : 0.050±0.018
These values may be compared to the largest proper motion reported up to now for a planetary nebula, which is 0.040±0.003 arcsec/yr for NGC 7293 (believed to be the nearest planetary nebula). The distance of NGC 7293 is estimated to be 212 pc (Cudworth, 1974); from this is would be reasonable to estimate that the quasar PHL 1033, LB 8956 and LB 8991 lie within a few hundred parsecs from the sun. There are large uncertainties in the proper motions of quasars listed in table 1. However, within the limitations of these uncertainties, it would be fair to say that the results for the other 27 quasars are similar to those of planetary nebulae, except of course NGC 7293. We find that the proper motion evidence supports the hypothesis that we have advanced in the previous section.
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That means thousands of light years away, not billions. |
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Robert Fritzius
Joined: 21 Aug 2007
Posts: 5
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| Posted: Sun Sep 09, 2007 1:44 pm Post subject: Re: Evidence for a Small Universe, van Maanen |
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| scordova wrote: |
Here is a picture of mysterious rings associated Supernova 1987A. It suggests there is maybe something we don't understand in terms of basic optics of what's happening in space.
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When the Hubble Space Telescope was pointed at the supernova remnant in 1994, however, curious rings were discovered. The origins of these rings still remains a mystery.
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I put together a webpage that shows what I think is evidence that SN 1987a is very close to us, close enough that proper motion effects of a binary star can be seen. Those expanding ring-like structures, seen in the HST images of the SN, do NOT have common centers.
Please see: SN 1987a, as a Possible Ritzian System
http://www.shadetreephysics.com/sn1987a.htm
Bob Fritzius |
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SCheesman
Joined: 31 Dec 1969
Posts: 45
Location: Ontario, Canada
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| Posted: Thu Sep 13, 2007 4:11 pm Post subject: SN 1987A as a result of the merger of two binary stars |
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The following is a link to paper in Science published 23 February, 2007 explaining the rings as the result of the merger of two binary stars:
http://www.sciencemag.org/cgi/content/abstract/315/5815/1103
The abstract is as follows:
| Quote: | The Triple-Ring Nebula Around SN 1987A: Fingerprint of a Binary Merger
Thomas Morris1,2 and Philipp Podsiadlowski1*
Supernova 1987A, the first naked-eye supernova observed since Kepler's supernova in 1604, defies a number of theoretical expectations. Its anomalies have long been attributed to a merger between two massive stars that occurred some 20,000 years before the explosion, but so far there has been no conclusive proof that this merger took place. Here, we present three-dimensional hydrodynamical simulations of the mass ejection associated with such a merger and the subsequent evolution of the ejecta, and we show that this accurately reproduces the properties of the triple-ring nebula surrounding the supernova.
1 Department of Astrophysics, University of Oxford, Oxford OX1 3RH, UK.
2 Max-Planck Institut für Astrophysik, Garching 85741, Germany.
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The evolution of the ejected mass from SN 1987A is being observed and tracked yearly by the Hubble space telescope. There is little doubt, considering the direct measurment of the change in the system, the spectral measurements of the light from the rings, and observations of the nature of the stars in the neighbourhood of the star, that SN 1987A is at the distance observed, and that the rings are real. |
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SCheesman
Joined: 31 Dec 1969
Posts: 45
Location: Ontario, Canada
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| Posted: Thu Sep 13, 2007 4:21 pm Post subject: Cool diagram showing the form and origin of SN 1987A rings |
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Check out this cool illustration of the rings of SN 1987A and their formation, taken from the Hubble Site:
http://imgsrc.hubblesite.org/hu/db/2007/10/images/i/formats/pdf.pdf
It shows quite clearly why they are not concentric.
Here, also is a current description of SN 1987A, with reports on the rings:
http://www.citebase.org/abstract?id=oai%3AarXiv.org%3Aastro-ph%2F0612177
Here is the abstract from that paper:
| Quote: | SN 1987A at the end of its second decade
Authors: Kjaer, Karina; Groeningsson, Per; Kotak, Rubina; Fransson, Claes; Leibundgut, Bruno
After nearly two decades at least five emission mechanisms can be found in SN 1987A. The ejecta continue to glow as a result of the radioactive decay of long-lived nuclei (mostly 44Ti), but is fading continuously because of the expansion and the reduced opacity. The nearly stationary rings around SN 1987A are still fluorescing from the recombination of matter originally excited by the soft X-ray emission from the shock breakout at explosion. The supernova shock reached the inner circumstellar ring about ten years ago and the forward shock is moving through the inner ring and leaves shocked material behind. This material is excited and accelerated. The reverse shock illuminates the fast-moving supernova ejecta as it catches up. And, finally light echoes in nearby interstellar matter can still be observed. We present here high resolution spectroscopy in the optical and integral-field spectroscopy in the near infrared of SN 1987A and its rings.
Comment: 8 pages, 6 figures, to be published in The Multicoloured Landscape of Compact Objects and their Explosive Origins, Proceedings of the Cefalu conference |
Finally, one last link showing the binary-merger theory as a poster, also on the Hubble site:
http://www.spacetelescope.org/images/html/heic0704j.html |
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Robert Fritzius
Joined: 21 Aug 2007
Posts: 5
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| Posted: Tue Jan 08, 2008 1:44 am Post subject: Re: Cool diagram showing the form and origin of SN 1987A rin |
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On my computer that pdf source seems to load about ten images but only one ever shows up. The diagram that does appear makes it look like the rings are a time-wise progression of conical sections. The sequence seems to be wrong in that the brightest, most recent ring is the central member of the conical sequence.
| Quote: | SN 1987A at the end of its second decade
See previous post for abstract.
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This abstract describes concentric circumplanar events which, to me, are not consistent with the obviously non-concentric rings associated with sn 1987a
Again, the images in this poster do not correspond to the non-concentric rings of sn 1987a. |
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SCheesman
Joined: 31 Dec 1969
Posts: 45
Location: Ontario, Canada
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| Posted: Tue Jan 08, 2008 9:14 am Post subject: Rings and cones. |
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Robert Fritzius: | Quote: | | Again, the images in this poster do not correspond to the non-concentric rings of sn 1987a. |
First, welcome back. It's getting too quiet around here. I've been meaning to post something on the origin of the moon just to stir things up.
The rings are axially concentric, but not coplanar; there is the bright central "equatorial" ring, which contains the majority of the energy, and two "polar" rings moving apart above and below the central ring. These two are the ones on the upper and lower "cones". The axis is tilted w.r.t. to our viewpoint (of course). Reflections not congruent with these three rings are due to interstellar nebulae.
I don't get 10 images, I think there is just one (big) image in the PDF; I expect the "10" in the URL is just for indexing. |
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SCheesman
Joined: 31 Dec 1969
Posts: 45
Location: Ontario, Canada
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| Posted: Tue Jan 08, 2008 11:55 am Post subject: More on the shape of the rings |
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The main text of the paper
http://www.citebase.org/fulltext?format=application%2Fpdf&identifier=oai%3AarXiv.org%3Aastro-ph%2F0612177
contains the following information about the shape and tilt of the (main) ring:
| Quote: | It is now possible to determine the rest frame velocity of the ring assuming that
the acceleration around the ring has been constant. This is clearly not the case, as
the flat-topped velocity distribution of Pab shows. There is a clear deviation from the
expected sine curve for a tilted ring. The reason is, of course, that the density of the
ring protrusions and the shock interaction are not the same around the ring. The eastern
part has had the first interaction and hence a higher shock velocity is expected in these
regions. Also, the ring is not simply inclined perpendicular to the line of sight but also
rotated out of the plane of the sky with the eastern sector more distant than the western
part. We derive from the velocity curve a rotation angle of ∼ 10◦, consistent with the
offset seen in the major axis of the ring on the sky (Jakobsen et al. 1991, Panagia et al.
1991). Nevertheless assuming that the asymmetries average out over the complete ring,
we can find the systemic velocity of the ring, and presumably of SN 1987A itself. A
first, preliminary analysis yields vSN1987A = 283±8 km s−1, which is consistent with
the value derived from the high-resolution UVES spectroscopy, 286.7±0.1 km s−1. |
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