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Re: [comets-ml] Tail still long (and will get longer!)

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  • jbortle@aol.com
    By physical necessity and as I ve pointed out previously, the dust tail of 2011 W3 SHOULD be continuing to lengthen...at least until the surface brightness of
    Message 1 of 4 , Jan 1, 2012
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      By physical necessity and as I've pointed out previously, the dust tail of
      2011 W3 SHOULD be continuing to lengthen...at least until the surface
      brightness of the outermost portions drop completely below the detection limits
      of the method being employed. For the unaided eye I'm afraid that this will
      occur fairly soon. However, for appropriately long exposed, highly
      processed, fairly small-scale images this interval should be considerably
      extended.

      If astro-imagers familiar with the sorts of image processing done to bring
      out the absolute threshold details in such objects as galaxies apply their
      techniques to appropriate images of the comet I see no reason for the
      ultimate length of the tail not turning out to be something in the order of
      50-60 degrees by mid January. I know that years ago when I dabbled in this area
      I could bring out details far beyond what I ever imagined were in the
      original images (although the pictures no longer were very pretty to look at!)

      J.Bortle




      In a message dated 1/1/2012 12:22:53 A.M. Eastern Standard Time,
      seargent@... writes:


      Hi Rob and all,
      Yes, I did put down a couple of wrong numbers (lack of sleep I guess).
      Still, it does not make a very great difference. The revised length comes out
      at 39 degrees ... and this time I checked the numbers! The end appeared to
      be near Theta Carinae, visible with averted vision only in "flashes".
      Perhaps it was averted imagination, but I think it was real.
      Cheers,
      David




      To: comets-ml@yahoogroups.com
      From: rmn@...
      Date: Sun, 1 Jan 2012 14:09:35 +1100
      Subject: Re: [comets-ml] Tail still long






      On Sun, 1 Jan 2012, David Seargent wrote:

      > The tail has cleared the brightest part of the MW and this morning
      > (Dec. 31. 1600 UT) I'm sure that I could trace it with averted vision
      > into Carina; a length of (wait for it!) 45 degrees! The sky was very
      > clear with a limiting naked-eye magnitude of around 6.5 or better.

      Hi David,
      I'd doubt this will be correct. My photos show the tail much more
      clearly than to the naked eye, up to 33 deg, just into Carina,
      but I can't trace it crossing the dark zone to the SE of eta Carinae.
      45 deg would take it over theta Carinae. Calculation error?

      Check my fish-eye shot from this morning at

      http://msowww.anu.edu.au/~rmn/C2011W3.htm

      I'll reorganise this page in the next few days.

      Cheers, Rob





      [Non-text portions of this message have been removed]



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

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      NOTICE: Material quoted or re-posted from the Comets Mailing List should
      be indicated by:

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      [Non-text portions of this message have been removed]
    • Rob
      Lester Barnes of South Australia has continued to produce a great series of widefield images of the comet night by night and with his permission I m posting a
      Message 2 of 4 , Jan 1, 2012
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        Lester Barnes of South Australia has continued to produce a great series of widefield images of the comet night by night and with his permission I'm posting a small animated gif of his shots from the last two mornings. Also a small gif of my images, quality not good especially this morning. Not conclusive by any means, but they appear to show the faint tail extending well out. In mine maybe at least 37-deg to IC 2602 (Southern Pleiades) and Lester's maybe out to the top of the frame (about 42-deg). Don't have exact times for Lester's - probably around 16:00 UT each morning.
        http://i727.photobucket.com/albums/ww271/Rob_Kau/Lestergifanim31Dec-01JanUT.gif
        http://i727.photobucket.com/albums/ww271/Rob_Kau/gifanim31Dec11-01Jan12.gif

        I observed the comet naked-eye last night (14:30, 01 Jan 2012 UT) and could see the tail with averted vision extending as far as Delta Muscae (~ 22 deg). The first degree or two from the head were not visible to me. Surface brightness was considerably less than the SMC.

        Cheers -

        Rob Kaufman
        Bright, Victoria, Australia


        --- In comets-ml@yahoogroups.com, jbortle@... wrote:
        >
        > By physical necessity and as I've pointed out previously, the dust tail of
        > 2011 W3 SHOULD be continuing to lengthen...at least until the surface
        > brightness of the outermost portions drop completely below the detection limits
        > of the method being employed. For the unaided eye I'm afraid that this will
        > occur fairly soon. However, for appropriately long exposed, highly
        > processed, fairly small-scale images this interval should be considerably
        > extended.
        >
        > If astro-imagers familiar with the sorts of image processing done to bring
        > out the absolute threshold details in such objects as galaxies apply their
        > techniques to appropriate images of the comet I see no reason for the
        > ultimate length of the tail not turning out to be something in the order of
        > 50-60 degrees by mid January. I know that years ago when I dabbled in this area
        > I could bring out details far beyond what I ever imagined were in the
        > original images (although the pictures no longer were very pretty to look at!)
        >
        > J.Bortle
        >
        >
        >
        >
        > In a message dated 1/1/2012 12:22:53 A.M. Eastern Standard Time,
        > seargent@... writes:
        >
        >
        > Hi Rob and all,
        > Yes, I did put down a couple of wrong numbers (lack of sleep I guess).
        > Still, it does not make a very great difference. The revised length comes out
        > at 39 degrees ... and this time I checked the numbers! The end appeared to
        > be near Theta Carinae, visible with averted vision only in "flashes".
        > Perhaps it was averted imagination, but I think it was real.
        > Cheers,
        > David
        >
        >
        >
        >
        > To: comets-ml@yahoogroups.com
        > From: rmn@...
        > Date: Sun, 1 Jan 2012 14:09:35 +1100
        > Subject: Re: [comets-ml] Tail still long
        >
        >
        >
        >
        >
        >
        > On Sun, 1 Jan 2012, David Seargent wrote:
        >
        > > The tail has cleared the brightest part of the MW and this morning
        > > (Dec. 31. 1600 UT) I'm sure that I could trace it with averted vision
        > > into Carina; a length of (wait for it!) 45 degrees! The sky was very
        > > clear with a limiting naked-eye magnitude of around 6.5 or better.
        >
        > Hi David,
        > I'd doubt this will be correct. My photos show the tail much more
        > clearly than to the naked eye, up to 33 deg, just into Carina,
        > but I can't trace it crossing the dark zone to the SE of eta Carinae.
        > 45 deg would take it over theta Carinae. Calculation error?
        >
        > Check my fish-eye shot from this morning at
        >
        > http://msowww.anu.edu.au/~rmn/C2011W3.htm
        >
        > I'll reorganise this page in the next few days.
        >
        > Cheers, Rob
        >
        >
        >
        >
        >
        > [Non-text portions of this message have been removed]
        >
        >
        >
        > ------------------------------------
        >
        > Comet Observations List: http://groups.yahoo.com/group/CometObs/
        > Comet Images List: http://groups.yahoo.com/group/Comet-Images/
        >
        > NOTICE: Material quoted or re-posted from the Comets Mailing List should
        > be indicated by:
        >
        > Comets Mailing List [date]
        > http://www.yahoogroups.com/group/comets-ml
        > Yahoo! Groups Links
        >
        >
        >
        >
        >
        >
        > [Non-text portions of this message have been removed]
        >
      • JS & EJ Gifford
        Congratulations, Rob. I got my first clear night for several days but was not able to pick the tail naked eye, after moonset in a dark sky, probably part due
        Message 3 of 4 , Jan 1, 2012
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          Congratulations, Rob. I got my first clear night for several days but was
          not able to pick the tail naked eye, after moonset in a dark sky, probably
          part due to old eyes. Even on the photos I took I could only see it as far
          as Gamma Muscae, so about 24 degrees. The photos show the head as pretty
          much gone, with the tail fading out to a point with decreasing brightness
          where the comet should be. We have had a good run, Thanks, Terry.

          Regards, Jim Gifford.



          _____

          From: comets-ml@yahoogroups.com [mailto:comets-ml@yahoogroups.com] On Behalf
          Of Rob
          Sent: Monday, 2 January 2012 8:38 AM
          To: comets-ml@yahoogroups.com
          Subject: [comets-ml] Re: Tail still long (and will get longer!)





          Lester Barnes of South Australia has continued to produce a great series of
          widefield images of the comet night by night and with his permission I'm
          posting a small animated gif of his shots from the last two mornings. Also a
          small gif of my images, quality not good especially this morning. Not
          conclusive by any means, but they appear to show the faint tail extending
          well out. In mine maybe at least 37-deg to IC 2602 (Southern Pleiades) and
          Lester's maybe out to the top of the frame (about 42-deg). Don't have exact
          times for Lester's - probably around 16:00 UT each morning.
          http://i727.photobucket.com/albums/ww271/Rob_Kau/Lestergifanim31Dec-01JanUT.
          gif
          http://i727.photobucket.com/albums/ww271/Rob_Kau/gifanim31Dec11-01Jan12.gif

          I observed the comet naked-eye last night (14:30, 01 Jan 2012 UT) and could
          see the tail with averted vision extending as far as Delta Muscae (~ 22
          deg). The first degree or two from the head were not visible to me. Surface
          brightness was considerably less than the SMC.

          Cheers -

          Rob Kaufman
          Bright, Victoria, Australia

          --- In comets-ml@yahoogroups.com <mailto:comets-ml%40yahoogroups.com> ,
          jbortle@... wrote:
          >
          > By physical necessity and as I've pointed out previously, the dust tail of

          > 2011 W3 SHOULD be continuing to lengthen...at least until the surface
          > brightness of the outermost portions drop completely below the detection
          limits
          > of the method being employed. For the unaided eye I'm afraid that this
          will
          > occur fairly soon. However, for appropriately long exposed, highly
          > processed, fairly small-scale images this interval should be considerably
          > extended.
          >
          > If astro-imagers familiar with the sorts of image processing done to bring

          > out the absolute threshold details in such objects as galaxies apply their

          > techniques to appropriate images of the comet I see no reason for the
          > ultimate length of the tail not turning out to be something in the order
          of
          > 50-60 degrees by mid January. I know that years ago when I dabbled in this
          area
          > I could bring out details far beyond what I ever imagined were in the
          > original images (although the pictures no longer were very pretty to look
          at!)
          >
          > J.Bortle
          >
          >
          >
          >
          > In a message dated 1/1/2012 12:22:53 A.M. Eastern Standard Time,
          > seargent@... writes:
          >
          >
          > Hi Rob and all,
          > Yes, I did put down a couple of wrong numbers (lack of sleep I guess).
          > Still, it does not make a very great difference. The revised length comes
          out
          > at 39 degrees ... and this time I checked the numbers! The end appeared to

          > be near Theta Carinae, visible with averted vision only in "flashes".
          > Perhaps it was averted imagination, but I think it was real.
          > Cheers,
          > David
          >
          >
          >
          >
          > To: comets-ml@yahoogroups.com <mailto:comets-ml%40yahoogroups.com>
          > From: rmn@...
          > Date: Sun, 1 Jan 2012 14:09:35 +1100
          > Subject: Re: [comets-ml] Tail still long
          >
          >
          >
          >
          >
          >
          > On Sun, 1 Jan 2012, David Seargent wrote:
          >
          > > The tail has cleared the brightest part of the MW and this morning
          > > (Dec. 31. 1600 UT) I'm sure that I could trace it with averted vision
          > > into Carina; a length of (wait for it!) 45 degrees! The sky was very
          > > clear with a limiting naked-eye magnitude of around 6.5 or better.
          >
          > Hi David,
          > I'd doubt this will be correct. My photos show the tail much more
          > clearly than to the naked eye, up to 33 deg, just into Carina,
          > but I can't trace it crossing the dark zone to the SE of eta Carinae.
          > 45 deg would take it over theta Carinae. Calculation error?
          >
          > Check my fish-eye shot from this morning at
          >
          > http://msowww.anu.edu.au/~rmn/C2011W3.htm
          >
          > I'll reorganise this page in the next few days.
          >
          > Cheers, Rob
          >
          >
          >
          >
          >
          > [Non-text portions of this message have been removed]
          >
          >
          >
          > ------------------------------------
          >
          > Comet Observations List: http://groups.yahoo.com/group/CometObs/
          > Comet Images List: http://groups.yahoo.com/group/Comet-Images/
          >
          > NOTICE: Material quoted or re-posted from the Comets Mailing List should
          > be indicated by:
          >
          > Comets Mailing List [date]
          > http://www.yahoogroups.com/group/comets-ml
          > Yahoo! Groups Links
          >
          >
          >
          >
          >
          >
          > [Non-text portions of this message have been removed]
          >





          [Non-text portions of this message have been removed]
        • Ian Musgrave & Peta O'Donohue
          G Day All Finally I can post again! Thanks for sharing Lester s Images Rob. I looked this morning (2Jan, 3:30 am AEDST) from the Western Victorian plains, sky
          Message 4 of 4 , Jan 2, 2012
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            G'Day All

            Finally I can post again! Thanks for sharing Lester's Images Rob.

            I looked this morning (2Jan, 3:30 am AEDST) from the Western Victorian
            plains, sky was fantastically clear but I couldn't see anything even with
            averted vision, probably due to rubbish eyesight. Have yet to analyse my
            photos to see if I picked anything up.

            Cheers! Ian

            Rob wrote:
            > Lester Barnes of South Australia has continued to produce a great series
            > of widefield images of the comet night by night and with his permission
            > I'm posting a small animated gif of his shots from the last two mornings.
            > Also a small gif of my images, quality not good especially this morning.
            > Not conclusive by any means, but they appear to show the faint tail
            > extending well out. In mine maybe at least 37-deg to IC 2602 (Southern
            > Pleiades) and Lester's maybe out to the top of the frame (about 42-deg).
            > Don't have exact times for Lester's - probably around 16:00 UT each
            > morning.
            > http://i727.photobucket.com/albums/ww271/Rob_Kau/Lestergifanim31Dec-01JanUT.gif
            > http://i727.photobucket.com/albums/ww271/Rob_Kau/gifanim31Dec11-01Jan12.gif
            >
            > I observed the comet naked-eye last night (14:30, 01 Jan 2012 UT) and
            > could see the tail with averted vision extending as far as Delta Muscae (~
            > 22 deg). The first degree or two from the head were not visible to me.
            > Surface brightness was considerably less than the SMC.
            >
            > Cheers -
            >
            > Rob Kaufman
            > Bright, Victoria, Australia
            >
            >
            > --- In comets-ml@yahoogroups.com, jbortle@... wrote:
            >>
            >> By physical necessity and as I've pointed out previously, the dust tail
            >> of
            >> 2011 W3 SHOULD be continuing to lengthen...at least until the surface
            >> brightness of the outermost portions drop completely below the detection
            >> limits
            >> of the method being employed. For the unaided eye I'm afraid that this
            >> will
            >> occur fairly soon. However, for appropriately long exposed, highly
            >> processed, fairly small-scale images this interval should be
            >> considerably
            >> extended.
            >>
            >> If astro-imagers familiar with the sorts of image processing done to
            >> bring
            >> out the absolute threshold details in such objects as galaxies apply
            >> their
            >> techniques to appropriate images of the comet I see no reason for the
            >> ultimate length of the tail not turning out to be something in the
            >> order of
            >> 50-60 degrees by mid January. I know that years ago when I dabbled in
            >> this area
            >> I could bring out details far beyond what I ever imagined were in the
            >> original images (although the pictures no longer were very pretty to
            >> look at!)
            >>
            >> J.Bortle
            >>
            >>
            >>
            >>
            >> In a message dated 1/1/2012 12:22:53 A.M. Eastern Standard Time,
            >> seargent@... writes:
            >>
            >>
            >> Hi Rob and all,
            >> Yes, I did put down a couple of wrong numbers (lack of sleep I guess).
            >> Still, it does not make a very great difference. The revised length
            >> comes out
            >> at 39 degrees ... and this time I checked the numbers! The end appeared
            >> to
            >> be near Theta Carinae, visible with averted vision only in "flashes".
            >> Perhaps it was averted imagination, but I think it was real.
            >> Cheers,
            >> David
            >>
            >>
            >>
            >>
            >> To: comets-ml@yahoogroups.com
            >> From: rmn@...
            >> Date: Sun, 1 Jan 2012 14:09:35 +1100
            >> Subject: Re: [comets-ml] Tail still long
            >>
            >>
            >>
            >>
            >>
            >>
            >> On Sun, 1 Jan 2012, David Seargent wrote:
            >>
            >> > The tail has cleared the brightest part of the MW and this morning
            >> > (Dec. 31. 1600 UT) I'm sure that I could trace it with averted vision
            >> > into Carina; a length of (wait for it!) 45 degrees! The sky was very
            >> > clear with a limiting naked-eye magnitude of around 6.5 or better.
            >>
            >> Hi David,
            >> I'd doubt this will be correct. My photos show the tail much more
            >> clearly than to the naked eye, up to 33 deg, just into Carina,
            >> but I can't trace it crossing the dark zone to the SE of eta Carinae.
            >> 45 deg would take it over theta Carinae. Calculation error?
            >>
            >> Check my fish-eye shot from this morning at
            >>
            >> http://msowww.anu.edu.au/~rmn/C2011W3.htm
            >>
            >> I'll reorganise this page in the next few days.
            >>
            >> Cheers, Rob
            >>
            >>
            >>
            >>
            >>
            >> [Non-text portions of this message have been removed]
            >>
            >>
            >>
            >> ------------------------------------
            >>
            >> Comet Observations List: http://groups.yahoo.com/group/CometObs/
            >> Comet Images List: http://groups.yahoo.com/group/Comet-Images/
            >>
            >> NOTICE: Material quoted or re-posted from the Comets Mailing List
            >> should
            >> be indicated by:
            >>
            >> Comets Mailing List [date]
            >> http://www.yahoogroups.com/group/comets-ml
            >> Yahoo! Groups Links
            >>
            >>
            >>
            >>
            >>
            >>
            >> [Non-text portions of this message have been removed]
            >>
            >
            >
            >
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