220p 20260820 dbartlett

The Dust Tail has Expanded to the Diameter of The Full Moon , Comet 220P/ McNaught on August 18th 2026
 

 
 

ASTROBIN-Full Resolution, animation and other Goodies:
 

https://app.astrobin.com/i/nnq6cy?r=0
 

 
 

Project Notes:
 

    Comet 220P/ McNaught continues to lengthen while the green coma continues to shrink. 
    Tail measured at 37.5arc minutes and brightness of the comet measured at magnitude of 8.6. 
    Considerable dust / IFN in the FOV. 
    With 3.5 hours of integration time the dusty tail appears less transparent and more opague. 
    I've over indulged the saturation of stars and comet. 

 

 
 

 
 

Observational details:
 

    Backyard setup 
    2xscopes Tandem: RASA11 D = 279mm; fl =620mm; F# 2.2 
    camera: asi6200mmP and asi6200mcP 
    Seeing: 3.5/5  
    Transparency: 8/10  
    Observer: DEBartlett 
    Location: June Lake, California, USA 

 

 
 

Image Info:
 

(All images processed solely using PixInsight and Comet Photometry Tycho-Tracker)
 

    Resampled 2x2 
    Acquisition...............94x180sec total 
    Resolution ............... 2.501 arcsec/px 
    Rotation ................. -2.390 deg 

 

 
 

Wide Field
 

    Field of view ............ 3d 9' 58.8" x 1d 51' 36.2" 
    Image center ............. RA: 2 57 37.272 Dec: +9 21 43.29 

 

 
 

Cropped
 

    Field of view ............ 1d 51' 47.9" x 1d 4' 39.2" 
    Image center ............. RA: 2 59 21.277 Dec: +9 19 51.17 

 

 
 

220P (McNaught)
 

ICQ line:
 

IIIYYYYMnL YYYY MM DD.DD eM/mm.m:r AAA.ATF/xxxx /dd.ddnDC /t.ttmANG ICQ XX*OBSxxf InT APERTURcamchip SFW C ## u.uu xx.x PIXELSIZE
 

220 2026 08 18.44 C 8.6 AR 28.0T 2H820 5.1 37.5m250 ICQ XX BARaeI a900C 5.09mZCP IMX TYT 0 U9*0.09 9.7 2.5s 2.5 Location: June Lake Overlook (MPC U66); Comment: Comet Alt. 44.3
 

 
 

COD U66
 

OBS
 

CATALOG: ATLAS2 - BAND: r (Sun Mag=-26.93)
 

 
 

 10x10 20x20 30x30 40x40 50x50 60x60 RSR FC COD
 

COMET UTC +/- +/- +/- +/- +/- +/- N FWHM CAT
 

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

220P 18/08/2026 10:32:03 12.42 11.52 11.05 10.70 10.46 10.27 92.4 18.4 U66
 

220P 18/08/2026 10:32:03* 0.08 0.08 0.08 0.08 0.08 0.08 49 31.1 ATL
 

 
 

 AFRHO LOG
 

COMET UTC DELTA r AP " MAG RSR CM +/- AFRHO OBS
 

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

220P 18/08/2026 10:32:03 1.18 1.68 23.31 11.33 92 1756 261 3.244 U66