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Re: [comets-ml] Moderator's absence

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  • Maik Meyer
    Jim, ... I wish I could! But since the company I work for has an agent in Australia I guess the prospects are not so good.. ;) Well, at least I had Hyakutake
    Message 1 of 15 , Jan 10, 2007
      Jim,

      > Can't you arrange some urgent business in Australia?

      I wish I could! But since the company I work for has an agent in
      Australia I guess the prospects are not so good.. ;)

      Well, at least I had Hyakutake at the zenith with a 65 deg tail. ;

      Cheers, Maik
      --
      If they give you ruled paper, write the other way. * Juan Ramon Jimenez
      ________________________________________________________________________
      maik@... http://www.comethunter.de
      German Comet Section http://www.fg-kometen.de
      http://groups.yahoo.com/group/comets-ml
    • cnj999
      Before this degenerates into an Yes it is, No it isn t situation, let me offer something of a guide to the visibility of comet-like objects in the daytime,
      Message 2 of 15 , Jan 10, 2007
        Before this degenerates into an "Yes it is, No it isn't" situation,
        let me offer something of a guide to the visibility of comet-like
        objects in the daytime, based on about half a dozen years of
        experimention on my part (and the basis for my near-sun article that
        appeared in the ICQ many years ago).

        At magnitude -1.5 : When the precise position is known, objects of
        this brightness are just visible with 80mm aperture, even within 5
        degrees of the Sun. They can be more easily detected with telescopes
        but are not "obvious".

        At magnitude -2.0 : Visible with larger, mounted binoculars, while
        easy with a modest telescope, even within 5 degrees of the Sun.

        At magnitude -2.5 : Easily seen in ordinary binoculars if mounted.
        Dramatically obvious with a modest telescope. Likely to show hints of
        the tail.

        At magnitude -3.0 : With ordinary binoculars, amazingly bright and
        almost equally as well seen as Venus in the daytime. Can simply be
        swept up with handheld 50mm binoculars and will likely show a short
        or rudimentary tail (Comet West in '76). Also can be detected with
        the unaided eye shortly before sunset (at the same time being very
        obvious in binoculars, complete with tail). Modest telescopes show
        considerable structure and significant tail with the Sun well above
        the horizon.

        At magnitude -4.0 : With careful attention, visible with the unaided
        eye throughout the day if more than 5 degrees from the Sun.
        Telescopes shows an almost uncomfortable degree of brightness (like
        that of Venus) to the nuclear region. The comet is visible in
        ordinary binoculars virtually right up to the Sun's limb.

        To me, the descriptions reported so far seem to equate to what I've
        personally seen with regard to objects of around -2.0 . Most
        unfortunately, it is cloudy at my location and I am unable to attempt
        any confirmatory observations myself.

        JBortle
      • gvnn64@libero.it
        ... John, the problem here is that the nice table you posted is based solely on visual impressions, i.e. very subjective, according to experience of the
        Message 3 of 15 , Jan 10, 2007
          > Before this degenerates into an "Yes it is, No it isn't" situation,
          > let me offer something of a guide to the visibility of comet-like
          > objects in the daytime

          John,
          the problem here is that the nice table you posted is based solely on visual impressions, i.e. very subjective, according to experience of the observer, the quality of the instruments used, the obsering conditions, etc. and I'm afraid that it will not provide any further useful insight on the matter under discussion, since the accuracy will still be in the order of ~magnitudes.

          It's clear that the main problem of C/2006 P1 is due to its extremely severe observing condition, and IMHO any kind of approach within the amateur's reach is currently unable to provide anything else than a "qualitative" indication of its brightness.

          Cheers,
          Giovanni


          ------------------------------------------------------
          Passa a Infostrada. ADSL e Telefono senza limiti e senza canone Telecom
          http://click.libero.it/infostrada10gen07
        • Greg Crinklaw
          ... Possible science aside, why do we need more than that? Greg -- Greg Crinklaw Astronomical Software Developer Cloudcroft, New Mexico, USA (33N, 106W, 2700m)
          Message 4 of 15 , Jan 10, 2007
            gvnn64@... wrote:
            > It's clear that the main problem of C/2006 P1 is due to its extremely
            > severe observing condition, and IMHO any kind of approach within the
            > amateur's reach is currently unable to provide anything else than a
            > "qualitative" indication of its brightness.

            Possible science aside, why do we need more than that?

            Greg

            --
            Greg Crinklaw
            Astronomical Software Developer
            Cloudcroft, New Mexico, USA (33N, 106W, 2700m)

            SkyTools Software for the Observer:
            http://www.skyhound.com/cs.html

            Skyhound Observing Pages:
            http://www.skyhound.com/sh/skyhound.html
          • gvnn64@libero.it
            ... Hi Greg, no problem from me: I was not the one blaming against the data scatter of current visual observations... Cheers, Giovanni ... Passa a Infostrada.
            Message 5 of 15 , Jan 10, 2007
              > Possible science aside, why do we need more than that?

              Hi Greg, no problem from me: I was not the one blaming against the data scatter of current visual observations...
              Cheers,
              Giovanni


              ------------------------------------------------------
              Passa a Infostrada. ADSL e Telefono senza limiti e senza canone Telecom
              http://click.libero.it/infostrada10gen07
            • P. Clay Sherrod
              Amen.....just as it has been for decades. There are going to be errors in reports and scattering of estimates. Clay ... Dr. P. Clay Sherrod Arkansas Sky
              Message 6 of 15 , Jan 10, 2007
                Amen.....just as it has been for decades. There are going to be errors in reports and
                scattering of estimates.

                Clay
                -------------
                Dr. P. Clay Sherrod
                Arkansas Sky Observatories
                Harvard MPC/ H43 (Conway)
                Harvard MPC/ H41 (Petit Jean Mountain)
                Harvard MPC/ H45 (Petit Jean Mtn. South)
                http://www.arksky.org/


                ----- Original Message -----
                From: "Greg Crinklaw" <crinklaw@...>
                To: <comets-ml@yahoogroups.com>
                Sent: Wednesday, January 10, 2007 10:23 AM
                Subject: Re: [comets-ml] Re: A word of caution to P1 observers


                > gvnn64@... wrote:
                >> It's clear that the main problem of C/2006 P1 is due to its extremely
                >> severe observing condition, and IMHO any kind of approach within the
                >> amateur's reach is currently unable to provide anything else than a
                >> "qualitative" indication of its brightness.
                >
                > Possible science aside, why do we need more than that?
                >
                > Greg
                >
                > --
                > Greg Crinklaw
                > Astronomical Software Developer
                > Cloudcroft, New Mexico, USA (33N, 106W, 2700m)
                >
                > SkyTools Software for the Observer:
                > http://www.skyhound.com/cs.html
                >
                > Skyhound Observing Pages:
                > http://www.skyhound.com/sh/skyhound.html
                >
                >
                > 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]
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                >
                > Yahoo! Groups Links
                >
                >
                >
              • David Nicholls
                ... Useful guidelines. I ve just come in from searching for P1 with a set of Oberwerk-style 45 degree 25x100 binoculars, alt-az tripod-mounted, without
                Message 7 of 15 , Jan 10, 2007
                  cnj999 wrote:

                  > At magnitude -1.5 : When the precise position is known, objects of
                  > this brightness are just visible with 80mm aperture, even within 5
                  > degrees of the Sun. They can be more easily detected with telescopes
                  > but are not "obvious".
                  >
                  > At magnitude -2.0 : Visible with larger, mounted binoculars, while
                  > easy with a modest telescope, even within 5 degrees of the Sun.
                  >
                  > At magnitude -2.5 : Easily seen in ordinary binoculars if mounted.
                  > Dramatically obvious with a modest telescope. Likely to show hints of
                  > the tail.

                  Useful guidelines. I've just come in from searching for P1 with a set
                  of "Oberwerk-style" 45 degree 25x100 binoculars, alt-az tripod-mounted,
                  without success. Noon time, Sun altitude about 75 deg. comet 65 deg.
                  (Canberra, lat. -35.3, good clear sky, and hot, too: 35 deg.C/95F). If
                  the comet were as bright as -2 or better, on the basis of these
                  guidelines, I would have hoped to see it.

                  DN
                  --
                  _________________________
                  David Nicholls
                  http://www.dcnicholls.com
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