161p 20261009 dbartlett

_161P_Hartley_IRAS_TandemRASA11s_asi6200mmP_asi6200mcP_80x45sec_20261009_215406_local_JuneLake_California_USA_DEBartlett
 

 
 

Comet 161P/Hartley-IRAS Hangs at Magnitude 11.7 on October 10th 2026
 

 
 

ASTROBIN-Full Resolution, animations and other Goodies:
 

https://app.astrobin.com/i/8cz3jw?r=0
 

 
 

Project Notes:
 

    Comet 161P/Hartley-IRAS has just past its closest approach to earth one week prior and is near maximum predicted brightness. 
    Very similar in shape and brightness to the newly reported comet P/2026 R2 Leonard, it is another greenish enveloping comet. 
    Comparisons are difficult thru visual scans since they differ in length of exposures/stacks caused by differing sky environments and apparent motions. 
    Widefield view has a number of interesting NGC and IC galaxies starting to show color and faint structure at the 620mm fl. 
    Slight tail extension to the 8 o'clock position. tail observed. 
    Color calibration was performed with PixInsight's SpectrophotometricColorCalibration process using a white balance of the spectral class of our sun as reference. 

 

 
 

Observational details:
 

    Backyard setup 
    2xscopes Tandem: RASA11 D = 279mm; fl =620mm; F# 2.2 
    camera: asi6200mmP and asi6200mcP 
    Seeing: 4/5  
    Transparency: 9/10 
    Observer: DEBartlett 
    Location: June Lake, California, USA 

 

 

Image Info:
 

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

    Bin1x1 
    WideField 
    Acquisition..............80x45sec total 
    Resolution ............... 1.249 arcsec/px 
    Rotation ................. 4.843 deg 
    Field of view ............ 2d 19' 56.7" x 1d 32' 23.2" 
    Image center ............. RA: 21 50 02.720 Dec: +2 26 31.98 

 

 
 

 
 

161P (Hartley-IRAS)
 

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
 

161 2026 10 10.22 C 11.7 AG 28.0T 2A845 3.7 1.7m103 ICQ XX BARaeI a 45C 3.66mZCP IMX TYT 0 U9*0.15 11.6 2.5s 2.5 Location: June Lake Overlook (MPC U66); Comment: Comet Alt. 53.4
 

 
 

COD U66
 

OBS
 

CATALOG: ATLAS2 - BAND: g (Sun Mag=-26.46)
 

 
 

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

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

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

161P 10/10/2026 05:15:44 15.39 14.72 14.34 14.02 13.82 13.64 52.7 19.6 U66
 

161P 10/10/2026 05:15:44* 0.14 0.14 0.14 0.14 0.14 0.14 41 14.6 ATL
 

 
 

 AFRHO LOG
 

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

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

161P 10/10/2026 05:15:44 0.55 1.43 50.14 13.82 53 43 11 1.631 U66