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
Getting plate-solving status, please wait...
Sh2-261 Lower's Nebula BiColor Ha & OIII, 


            Douglas J Struble
Sh2-261 Lower's Nebula BiColor Ha & OIII

Sh2-261 Lower's Nebula BiColor Ha & OIII

Technical card

Resolution: 3053x2444

Dates:Feb. 25, 2018April 22, 2018

Astrodon Ha 5nm: 104x240" (gain: 139.00) -20C bin 1x1
Astrodon OIII 3nm: 66x240" (gain: 139.00) -20C bin 1x1

Integration: 11.3 hours

Darks: ~50

Flats: ~50

Bias: ~250

Avg. Moon age: 8.33 days

Avg. Moon phase: 59.57%

Bortle Dark-Sky Scale: 6.00 job: 2045091

RA center: 92.217 degrees

DEC center: 15.766 degrees

Pixel scale: 0.675 arcsec/pixel

Orientation: 23.682 degrees

Field radius: 0.366 degrees

Locations: Backyard Red Zone Observatory, Taylor, MI, Michigan, United States

Data source: Backyard


Sh2-261 Lower's Nebula is super faint. I was hoping to finish it off in the Hubble Palette, but my main Astro-Physics Mach1 mount was gone for a month for warranty repair, so I lost a lot of time. It is now dipping into the west with less than a half hour to work with each night, so had to call it here in this bicolor palette.

The HII region Sh 2-261 is often called Lower's nebula because it appears on a photographic plate taken by the father-and-son team of Harold and Charles Lower in 1939.

The Lowers were amateur astronomers, accomplished telescope makers and pioneering astrophotographers from San Diego, California. Harold Lower published a pamphlet in 1939 describing an 8 inch Schmidt camera that he and his son had constructed several years previously. He notes that the camera has been especially useful in photographing what are now called HII regions.



Douglas J Struble
License: None (All rights reserved)

Sky plot

Sky plot


Sh2-261 Lower's Nebula BiColor Ha & OIII, 


            Douglas J Struble