Cookie consent

AstroBin saves small pieces of text information (cookies) on your device in order to deliver better content and for statistical purposes. You can disable the usage of cookies by changing the settings of your browser. By browsing AstroBin without changing the browser settings, you grant us permission to store that information on your device.

I agree
Contains:  M40, PGC2572162, PGC2572871, PGC2576158, PGC2576162, PGC2576239, PGC39934
Getting plate-solving status, please wait...
M40 (Winnecke 4) RGB - 15 April 2020, 


            Geof Lewis
Powered byPixInsight

M40 (Winnecke 4) RGB - 15 April 2020

Technical card

Dates:April 15, 2020

Astronomik B 1.25" Type IIc: 12x60" -10C bin 2x2
Astronomik G 1.25" Type IIc: 12x60" -10C bin 2x2
Astronomik R 1.25" Type IIc: 12x60" -10C bin 2x2

Integration: 0.6 hours

Darks: ~20

Flats: ~20

Flat darks: ~20

Bias: ~20

Avg. Moon age: 22.66 days

Avg. Moon phase: 44.59%

Bortle Dark-Sky Scale: 4.00 job: 3428046

RA center: 12h 22' 17"

DEC center: +58° 4' 47"

Pixel scale: 0.855 arcsec/pixel

Orientation: 93.382 degrees

Field radius: 0.239 degrees

Resolution: 1621x1195

Data source: Backyard


This is possibly the most bizarre of Charles Messier's list of 'it's not a comet' targets, though to be fair to him, in 1764 he was searching for a nebula that had been reported in the area by Johannes Hevelius, of which nothing has ever been found. What Messier found was an optical double, which I've only imaged as I need it for my personal Messier collection. It was rediscovered by Friedrich August Theodor Winnecke in 1863, hence the alternative designation of Winnecke 4. The star field is so boring that for the first time ever I used Noel Carboni's Astronomy Tools to add artificial diffraction spikes....



Geof Lewis
License: None (All rights reserved)

Sky plot

Sky plot


M40 (Winnecke 4) RGB - 15 April 2020, 


            Geof Lewis