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Red/Blue shift due to Doppler effect = assumption?

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#51 russell23

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Posted 03 November 2012 - 01:51 PM

There are people over on the imaging forums who are perfectly capable of making very deep images of this galaxy to get a better view at least of the morphology.

Here's another very interesting case because there is little doubt that the two objects are adjacent - the star-forming knots are identical in size and shape:

http://en.wikipedia.org/wiki/NGC_1232

NED 1232
http://ned.ipac.calt...bjname=NGC 1232
Red shift distance 95 million LY

NED 1232A
http://ned.ipac.calt...jname=NGC 1232A
Red shift distance 390 million LY

-drl


And you can add to this analysis. The companion galaxy is NGC 1232A and is morphologically an SBm type dwarf spiral. There are 12 of these galaxies with either Cepheid distances or in the Virgo cluster and Ursa Major cluster and with measured B-band isophotal diameters. The 12 SBm galaxies in question have a typical linear diamter of 6.8 +/- 3.5 kiloparsecs (kpc) with a range of 2.7kpc to 13.1kpc.

NGC 1232A would have a linear diamter of 23.3 kpc at its Hubble distance which then is 4.7 standard deviations above the mean. NGC 1232 has a distance of 17.4 Mpc from the Tully-Fisher relation. At this distance NGC 1232A would have a diameter of 4.4 kpc which falls nicely in the range of diameters for local SBm galaxies.

The same argument can be applied to the absolute magnitude of this galaxy. At the Hubble distance the absolute magnitude of NGC 1232A is -19.72 (B-band magnitude) - which is what is expected for a moderate sized spiral of Sa, Sb, and Sc types and is much too luminous for an SBm type spiral. A the NGC 1232 Tully-Fisher distance NGC 1232A would have an absolute magnitude of -16.10 which is in the normal range for dwarf galaxies such as SBm spirals.

Dave

#52 Neutrino?

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Posted 03 November 2012 - 08:27 PM

Between work and other survival activities, I work on just this, and will publish when it's time :) The equations are beastly hard to solve and make GR look like freshman physics. But there are solutions! which is good to know.

The key problem is to set the scale of EM vs gravity from observation of the CMB. That will enable a prediction of what happens in a condensed object. That's my goal.

-drl


Where's the psuedo-Dirac eq paper? It's not available.

#53 deSitter

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Posted 03 November 2012 - 11:29 PM

It had an argument that I realized was wrong. Repairs in progress.

-drl

#54 deSitter

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Posted 04 November 2012 - 09:08 AM

There are people over on the imaging forums who are perfectly capable of making very deep images of this galaxy to get a better view at least of the morphology.

Here's another very interesting case because there is little doubt that the two objects are adjacent - the star-forming knots are identical in size and shape:

http://en.wikipedia.org/wiki/NGC_1232

NED 1232
http://ned.ipac.calt...bjname=NGC 1232
Red shift distance 95 million LY

NED 1232A
http://ned.ipac.calt...jname=NGC 1232A
Red shift distance 390 million LY

-drl


And you can add to this analysis. The companion galaxy is NGC 1232A and is morphologically an SBm type dwarf spiral. There are 12 of these galaxies with either Cepheid distances or in the Virgo cluster and Ursa Major cluster and with measured B-band isophotal diameters. The 12 SBm galaxies in question have a typical linear diamter of 6.8 +/- 3.5 kiloparsecs (kpc) with a range of 2.7kpc to 13.1kpc.

NGC 1232A would have a linear diamter of 23.3 kpc at its Hubble distance which then is 4.7 standard deviations above the mean. NGC 1232 has a distance of 17.4 Mpc from the Tully-Fisher relation. At this distance NGC 1232A would have a diameter of 4.4 kpc which falls nicely in the range of diameters for local SBm galaxies.

The same argument can be applied to the absolute magnitude of this galaxy. At the Hubble distance the absolute magnitude of NGC 1232A is -19.72 (B-band magnitude) - which is what is expected for a moderate sized spiral of Sa, Sb, and Sc types and is much too luminous for an SBm type spiral. A the NGC 1232 Tully-Fisher distance NGC 1232A would have an absolute magnitude of -16.10 which is in the normal range for dwarf galaxies such as SBm spirals.

Dave


Yes, very excellent point.

Here's a larger image - look below the galaxy - there are strange red spindles everywhere, some well defined, some just emerging. There is one embedded in the galaxy itself at about the 2-o'clock position, coincident with a thick dust lane. There are several dwarfs to the left which are of the spindle type with one small tendril emerging from either end. One always sees these spindles in the vicinity of active galaxies.

http://www.robgendle...ubaru-ESO-L.jpg

-drl

#55 BillFerris

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Posted 04 November 2012 - 10:45 AM

As points of reference, in his 1988 publication, Nearby Galaxies Catalog, Tully includes distances of 20.0 megaparsecs (Mpc) and 21.1 megasparsecs, respectively, for NGC 1232 and NGC 1232A. The respective distance modulus data for these galaxies are 31.50 Mpc (N1232) and 31.62 Mpc (N1232A).

Bill in Flag






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