2023a3 20241020 dbartlett

No moonlight at last, back in my backyard imaging Comet C/2023 A3 Tsuchinshan-ATLAS Oct 20 2024UT.  Overworked this comet data attempting to bring out fine tail structure, nuclear complexities and as much dust tail in this  RASA11 3 panel mosaic as I dare.  Not very pretty.  Skies were pristine with FWHM averaging better than 2.5 and sky transparency at its best in our mountain climate.  With the apparent speed of the comet exposures longer than 7 seconds would show cometary trailing of 1 arc second so I opted on 15 seconds or less.  Each panel had less than five minutes of total integration time. Hence the mess!
Dan
 
 
 
Full resolution link:
https://astrob.in/kmmu9w/0/
 

Observational Notes:
scope: RASA11  fl620mm F/2
exposures: Panel1 56 x 5 sec, panel2 29 x15sec, panel3 28 x 15 sec, 
Seeing: 4.5/5
Transparency: 9/10
Observer: DEBartlett
Place: JuneLake California USA (Altitude +2357m)
 
Image Info (all ):
(All images processed solely using PixInsight)
 
Panel1 (Right)
Projection ............... Gnomonic
Projection origin ........ [2376.048417 1542.978816] px -> [RA: 16 27 53.764  Dec:  +2 24 22.03]
Resolution ............... 2.506 arcsec/px
Rotation ................. 0 deg
Reference system ......... ICRS
Observation start time ... 2024-10-20 02:16:28 UTC
Observation end time ..... 2024-10-20 02:43:56 UTC
Geodetic coordinates ..... 119 04 46 W  37 46 30 N  2357 m
Focal distance ........... 618.90 mm
Pixel size ............... 7.52 um
Field of view ............ 3d 18' 29.7" x 2d 8' 54.3"
Image center ............. RA: 16 27 53.763  Dec:  +2 24 22.03  ex: -0.002219 px  ey: -0.001141 px
Image bounds:
   top-left .............. RA: 16 34 39.448  Dec:  +3 25 35.05  ex: -1.098051 px  ey: -1.103970 px
   top-right ............. RA: 16 21 24.535  Dec:  +3 31 47.28  ex: +1.099130 px  ey: -1.108508 px
   bottom-left ........... RA: 16 34 22.311  Dec:  +1 16 48.16  ex: -1.092013 px  ey: +0.430184 px
   bottom-right .......... RA: 16 21 08.505  Dec:  +1 22 57.99  ex: +2.156162 px  ey: +0.465197 px
===============================
 
Panel2 (middle):
Projection origin ........ [2394.080517 1597.109859] px -> [RA: 16 36 51.124  Dec:  +3 00 50.33]
Resolution ............... 2.506 arcsec/px
Rotation ................. 1.824 deg
Reference system ......... ICRS
Observation start time ... 2024-10-20 02:47:05 UTC
Observation end time ..... 2024-10-20 02:47:20 UTC
Geodetic coordinates ..... 119 04 46 W  37 46 30 N  2357 m
Focal distance ........... 618.93 mm
Pixel size ............... 7.52 um
Field of view ............ 3d 19' 59.2" x 2d 13' 24.5"
Image center ............. RA: 16 36 51.124  Dec:  +3 00 50.33  ex: -0.010632 px  ey: +0.001801 px
Image bounds:
   top-left .............. RA: 16 43 40.455  Dec:  +4 04 17.06  ex: -1.552863 px  ey: -1.109934 px
   top-right ............. RA: 16 30 18.614  Dec:  +4 10 32.24  ex: +0.129591 px  ey: -1.370848 px
   bottom-left ........... RA: 16 43 22.440  Dec:  +1 50 57.63  ex: -1.086544 px  ey: +0.009744 px
   bottom-right .......... RA: 16 30 02.115  Dec:  +1 57 09.78  ex: +0.109807 px  ey: +0.008781 px
 
===============================
 
Panel3 (left):
Projection ............... Gnomonic
Projection origin ........ [2394.011505 1596.874368] px -> [RA: 16 46 02.234  Dec:  +4 01 56.27]
Resolution ............... 2.507 arcsec/px
Rotation ................. 1.830 deg
Reference system ......... ICRS
Observation start time ... 2024-10-20 03:07:25 UTC
Observation end time ..... 2024-10-20 03:07:40 UTC
Geodetic coordinates ..... 119 04 46 W  37 46 30 N  2357 m
Focal distance ........... 618.77 mm
Pixel size ............... 7.52 um
Field of view ............ 3d 20' 2.4" x 2d 13' 26.6"
Image center ............. RA: 16 46 02.234  Dec:  +4 01 56.28  ex: -0.007401 px  ey: +0.000847 px
Image bounds:
   top-left .............. RA: 16 52 52.242  Dec:  +5 05 21.45  ex: -1.106154 px  ey: -1.048007 px
   top-right ............. RA: 16 39 29.094  Dec:  +5 11 35.71  ex: +0.124179 px  ey: -1.610258 px
   bottom-left ........... RA: 16 52 33.852  Dec:  +2 52 02.11  ex: -1.097724 px  ey: +0.007555 px
   bottom-right .......... RA: 16 39 12.733  Dec:  +2 58 12.58  ex: +0.110128 px  ey: +0.006286 px