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Re: [stereohunter] Re: Phaethon showed cometary activity?

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  • Alan Watson
    Gidday Diitry , some further info for you. ... Some positions in Stereo Hi1B, too hard to detect after these. (0,0) Upleft image pixvalue x y slie 17
    Message 1 of 16 , Jul 4, 2009
      Gidday Diitry ,
      some further info for you.
      >Simultaneous observations from both STEREO spacecraft may help us to know is this brightness caused by phase effect (asteroid behavior) or not (comet behavior).
      Some positions in Stereo Hi1B, too hard to detect after these.
      (0,0) Upleft image   pixvalue  x  y  slie
      17 200906:20090621_020901_s4h1B 117.0299 9 566 4
      18 200906:20090621_040901_s4h1B 112.6499 21 560 7
      19 200906:20090621_080901_s4h1B 81.1234 50 548 13
      20 200906:20090621_104901_s4h1B 65.6277 68 541 17
      21 200906:20090621_124901_s4h1B 56.2850 80 535 20
      22 200906:20090621_140901_s4h1B 53.6190 88 531 22
      23 200906:20090621_152901_s4h1B 35.5949 98 526 24
      24 200906:20090621_212901_s4h1B 31.3209 135 510 33
      25 200906:20090621_232901_s4h1B 17.8045 146 505 36
       
      Also,
      >I also found one more visibility period of Phaethon near perihelion. It
      was on 2007 Dec. 28 - 2008 Jan. 14 (STEREO-B satellite).
      I have looked around this period in the STEREO A and STEREO B images for a similar fast moving object , but cannot detect it. 
       
      I don't know how to do correct photmetry on these images , but can measure the values of each position that result form how I have processed the images.
      Would you like that information?
       
      kind regards, Alan Watson
       
    • Alan Watson
      sorry Dimitry ...m.....ummmmm rgds al ... From: Alan Watson To: stereohunter@yahoogroups.com Sent: Saturday, July 04, 2009 5:54 PM Subject: Re:
      Message 2 of 16 , Jul 4, 2009
        sorry "Dimitry" ...m.....ummmmm  rgds al
        ----- Original Message -----
        Sent: Saturday, July 04, 2009 5:54 PM
        Subject: Re: [stereohunter] Re: Phaethon showed cometary activity?

        Gidday Diitry ,
        some further info for you.
        >Simultaneous observations from both STEREO spacecraft may help us to know is this brightness caused by phase effect (asteroid behavior) or not (comet behavior).
        Some positions in Stereo Hi1B, too hard to detect after these.
        (0,0) Upleft image   pixvalue  x  y  slie
        17 200906:20090621_ 020901_s4h1B 117.0299 9 566 4
        18 200906:20090621_ 040901_s4h1B 112.6499 21 560 7
        19 200906:20090621_ 080901_s4h1B 81.1234 50 548 13
        20 200906:20090621_ 104901_s4h1B 65.6277 68 541 17
        21 200906:20090621_ 124901_s4h1B 56.2850 80 535 20
        22 200906:20090621_ 140901_s4h1B 53.6190 88 531 22
        23 200906:20090621_ 152901_s4h1B 35.5949 98 526 24
        24 200906:20090621_ 212901_s4h1B 31.3209 135 510 33
        25 200906:20090621_ 232901_s4h1B 17.8045 146 505 36
         
        Also,
        >I also found one more visibility period of Phaethon near perihelion. It was on 2007 Dec. 28 - 2008 Jan. 14 (STEREO-B satellite).
        I have looked around this period in the STEREO A and STEREO B images for a similar fast moving object , but cannot detect it. 
         
        I don't know how to do correct photmetry on these images , but can measure the values of each position that result form how I have processed the images.
        Would you like that information?
         
        kind regards, Alan Watson
         

      • Ian Musgrave & Peta O'Donohue
        G Day All ... In the H1A images Phaeton is deep within coronal ejections. I m not sure how it s possible to do photometery under these circumstances (even if I
        Message 3 of 16 , Jul 4, 2009
          G'Day All

          At 05:24 PM 4/07/2009, Alan wrote:
          >[snip]
          >I don't know how to do correct photmetry on these images , but can
          >measure the values of each position that result form how I have
          >processed the images.
          >Would you like that information?

          In the H1A images Phaeton is deep within coronal ejections. I'm not
          sure how it's possible to do photometery under these circumstances
          (even if I *did* know how to do photometery)

          Cheers! Ian

          ======================================================
          Ian Musgrave Peta O'Donohue, Jack Francis, Michael James and Andrew
          Thomas Musgrave
          reynella@... http://home.mira.net/~reynella/
          Southern Sky Watch http://www.abc.net.au/science/space/default.htm
          (scroll down right hand menu)
          AstroBlogg http://astroblogger.blogspot.com/
          Contributing Editor, Sky & Space
          http://www.skyandspace.com.au/public/home.ehtml
        • Ian Musgrave & Peta O'Donohue
          G Day All ... It may be am illusion, but Paeton seems a bit more extended than I would expect for its supposed brightness. Hint of a tail or just smeared
          Message 4 of 16 , Jul 4, 2009
            G'Day All

            At 06:10 PM 4/07/2009, you wrote:
            >G'Day All
            >
            >At 05:24 PM 4/07/2009, Alan wrote:
            > >[snip]
            > >I don't know how to do correct photmetry on these images , but can
            > >measure the values of each position that result form how I have
            > >processed the images.
            > >Would you like that information?
            >
            >In the H1A images Phaeton is deep within coronal ejections. I'm not
            >sure how it's possible to do photometery under these circumstances
            >(even if I *did* know how to do photometery)

            It may be am illusion, but Paeton seems a bit more extended than I
            would expect for its supposed brightness. Hint of a tail or just
            smeared pixels?

            Cheers! Ian

            ======================================================
            Ian Musgrave Peta O'Donohue, Jack Francis, Michael James and Andrew
            Thomas Musgrave
            reynella@... http://home.mira.net/~reynella/
            Southern Sky Watch http://www.abc.net.au/science/space/default.htm
            (scroll down right hand menu)
            AstroBlogg http://astroblogger.blogspot.com/
            Contributing Editor, Sky & Space
            http://www.skyandspace.com.au/public/home.ehtml
          • Dimitry Chestnov
            ... In IAUC 9054, Karl noted a very short radial elongation (perpendicular to the direction of motion) that was possibly a line-of-sight effect related to its
            Message 5 of 16 , Jul 4, 2009
              --- In stereohunter@yahoogroups.com, "Alan Watson" <awat4309@...> wrote:
              >
              >
              > I don't know how to do correct photmetry on these images , but can measure the values of each position that result form how I have processed the images.
              > Would you like that information?
              >


              --- In stereohunter@yahoogroups.com, Ian Musgrave & Peta O'Donohue <reynella@...> wrote:
              >
              >
              > It may be an illusion, but Paeton seems a bit more extended than I
              > would expect for its supposed brightness. Hint of a tail or just
              > smeared pixels?
              >

              In IAUC 9054, Karl noted "a very short radial elongation (perpendicular to the direction of motion) that was possibly a line-of-sight effect related to its passage through a reasonably dense, higher-speed solar outflow stream", "the apparent brightness increased significantly (about 2 mag or more)" and "more formal photometry will be performed later".

              Regards,
              Dimirty
            • Ian Musgrave & Peta O'Donohue
              G Day All ... Meh! I ve been banging my head against photometry for this thing and I just cant do it, the image brightness is to variable, even my comparison
              Message 6 of 16 , Jul 5, 2009
                G'Day All

                At 06:56 PM 4/07/2009, Dimirty wrote:
                >--- In stereohunter@yahoogroups.com, "Alan Watson" <awat4309@...> wrote:
                >
                > > I don't know how to do correct photmetry on these images , but
                > can measure the values of each position that result form how I have
                > processed the images.
                > > Would you like that information?
                >--- In stereohunter@yahoogroups.com, Ian Musgrave & Peta O'Donohue
                ><reynella@...> wrote:
                > >
                > >
                > > It may be an illusion, but Paeton seems a bit more extended than I
                > > would expect for its supposed brightness. Hint of a tail or just
                > > smeared pixels?
                > >
                >
                >In IAUC 9054, Karl noted "a very short radial elongation
                >(perpendicular to the direction of motion) that was possibly a
                >line-of-sight effect related to its passage through a reasonably
                >dense, higher-speed solar outflow stream", "the apparent brightness
                >increased significantly (about 2 mag or more)" and "more formal
                >photometry will be performed later".

                Meh! I've been banging my head against photometry for this thing and
                I just cant do it, the image brightness is to variable, even my
                comparison stars are jumping about in brightness. Still, Phaeton is
                near invisible in the images from the 19th, very visible in the 20th
                and fades rapidly in the 21st. And I'm certain that the image is
                extended. Still without accurate photometry it's going to be hard to
                say anything.

                Cheers! Ian

                ======================================================
                Ian Musgrave Peta O'Donohue, Jack Francis, Michael James and Andrew
                Thomas Musgrave
                reynella@... http://home.mira.net/~reynella/
                Southern Sky Watch http://www.abc.net.au/science/space/default.htm
                (scroll down right hand menu)
                AstroBlogg http://astroblogger.blogspot.com/
                Contributing Editor, Sky & Space
                http://www.skyandspace.com.au/public/home.ehtml
              • algwat
                Gidday all, My view of Phaethon passing through perihelion. kind regards, Alan Just follow this link to see the video:
                Message 7 of 16 , Jul 9, 2009
                  Gidday all,
                  My view of Phaethon passing through perihelion.
                  kind regards, Alan

                  Just follow this link to see the video:
                  http://www.flickr.com/photos/40303621@N03/3705787107/

                  (If the link doesn't work, try copying and pasting it from this email into your browser's address bar.)
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