103P/Hartley + Eskimo Nebula 2023-Oct-12 Dan Bartlett

Eskimo Nebula has Flyby of Icy Comet, 103P/ Hartley, at Perihelion, 2023-10-12

Okay, this was a doozy. 416 x15 second exposures were taken with a C14 HyperStar under near ideal sky conditions. Initially I was planning on 60 seconds but reduced the exposure length to 45 seconds, then to 30 seconds and finally settled on 15 seconds. Why the adjustment? SGP showed the Eskimo nebula was overexposed on ALL accounts with 15 seconds showing the least amount of clipping in the un-stretched view on the computer screen.

When processing, I used a Game script mask to cover up the planetary nebula when stretching the rest of the image. That means the planetary nebula is still in its linear state - un-stretched.

Comet 103/ Hartley reached perihelion on this date and is projected to be around peak brightness for this time period. Really no comparison between comet and planetary nebula, however it is an interesting view at full scale/full resolution. Even more interesting is that NGC 2392 (The Eskimo Neb) holds up rather well at 2 x 1 magnification. Easy on the star shape comments, after all the scope is a SCT not a premium refractor.

Thanks!
Dan

ASTROBIN-Full resolution: https://astrob.in/w9mmyg/0/

Observational details:
Backyard setup
scope: C14 D = 356mm; fl =729mm; F# 2
camera: asi 2600mcP
exposure: 416 x15 sec
Seeing: 4/5 Transparency: 9/10
Observer: DEBartlett
Location: June Lake, California, USA


UnCropped Image details(Starless Version):
Projection ............... Gnomonic
Projection origin ........ [1920.683170 1080.338794] px -> [RA: 7 27 59.222 Dec: +21 04 48.52]
Resolution ............... 1.064 arcsec/px
Rotation ................. -2.975 deg
Reference system ......... ICRS
Observation start time ... 2023-10-12 11:34:30 UTC
Observation end time ..... 2023-10-12 11:34:45 UTC
Geodetic coordinates ..... 119 04 46 W 37 46 30 N 2357 m
Focal distance ........... 728.90 mm
Pixel size ............... 3.76 um
Field of view ............ 1d 8' 5.8" x 38' 18.2"
Image center ............. RA: 7 27 59.228 Dec: +21 04 48.56 ex: +0.120950 px ey: +0.262557 px
Image bounds:
top-left .............. RA: 7 30 20.962 Dec: +21 25 37.57 ex: -0.030686 px ey: -0.021209 px
top-right ............. RA: 7 25 28.826 Dec: +21 22 06.43 ex: +0.020644 px ey: -0.020959 px
bottom-left ........... RA: 7 30 28.750 Dec: +20 47 23.35 ex: -0.425858 px ey: +0.074182 px
bottom-right .......... RA: 7 25 38.000 Dec: +20 43 52.05 ex: +0.379520 px ey: +0.666260 px

ImageInfo CloseUp (Star Versions)
Resolution ............... 1.064 arcsec/px
Rotation ................. -2.955 deg
Focal distance ........... 728.80 mm
Pixel size ............... 3.76 um
Field of view ............ 45' 48.7" x 31' 58.7"
Image center ............. RA: 7 28 12.360 Dec: +21 05 50.68 ex: +0.069708 px ey: +0.027877 px
Image bounds:
top-left .............. RA: 7 29 47.082 Dec: +21 22 57.62 ex: +0.512363 px ey: -0.056317 px
top-right ............. RA: 7 26 30.506 Dec: +21 20 36.43 ex: -0.032788 px ey: -0.125826 px
bottom-left ........... RA: 7 29 53.735 Dec: +20 51 01.59 ex: +0.066117 px ey: -0.011703 px
bottom-right .......... RA: 7 26 37.976 Dec: +20 48 39.36 ex: +0.104351 px ey: -0.094174 px