Fun facts
Lower’s nebula (LBN 863, Sh2-261 or Sharpless 261) is found in the constellation Orion. Sh2-261 is a large faint region of predominantly ionized hydrogen. The nebula is named after Harold and Charles Lower who discovered this nebula in 1939.
Apparent Dimensions: 42’ x 30’
Constellation: Orion
Designations: SH2-261, LBN863
{From: https://skyandtelescope.org/online-gallery/lowers-nebula-in-orion-sh2-261/ and Stellarium}
Capture Notes
On 2025’s New Years Eve weekend (29-31Dec2024), we were able to get out for a final hoorah of dark skies with a couple of clear, albeit very windy, nights at the Mills Canyon rim in New Mexico’s Kiowa National Grassland. We got to the site and easily situated and leveled the Beast and made quick work of setting up camp (I’d convinced Paul to not bring the canopy because of the forecasted winds of 25+ mph). I set up both Big Bertha and the Southern Cross to take maximum advantage of the waning nebula “season” and our two nights in dark skies.
On the second night (30Dec2024) during dinner, we decided, after a full day of brutal winds and staring at the forecast for temperatures dropping into the teens that night, that we would cut our trip short and drive home on New Year’s Eve. Since M78 Casper set at about 03:20MST, I decided to use the hour left in the dark skies to gather an hour’s worth of data on SH2-261 Lower’s Nebula – to see if there was any colors (besides red) that were not coming out in the 1 December capture from the HCH front patio. So, I went out and quickly made the swap from M78 to SH2-261 to collect until both SH2-261 and IC405 (that I was collecting on with SC) set at 0430.
By stacking the very small data set – there didn’t appear to be any additional colors – so the image here is comprised of data captured at Mills Canyon Rim on 30 Dec 2024 and the data captured at HCH on 1 Dec 2024.
Sequence Plan (1Dec2024, HCH): Gain: 158, Temp: -0°C, offset=30. 85x300sec. Total: 425 minutes (7:05hrs). Total capture time: 1Dec2024, 2206 – 2Dec2024, 0553 MST. Images captured: 2206 – 0131MST; 0141 – 0553MST with the break being for the meridian flip.
Sequence Plan (30Dec2024, MillsRim): Gain: 158, Temp: -0°C, offset=30. 12x300sec. Total: 60 minutes (1:00hr). Captured: 31Dec2024, 03:46MST – 04:47MST.
Equipment
Equipment: All equipment controlled by HP Probook running Sequence Generator Pro v4.4.0.1441. DSO-CTRL2 on 1Dec2024. DSO-CTRL3 on 30Dec2024.
- Imaging (HCH, 1Dec2024): ZWO ASI2400MC imaging camera on (Big Bertha) Orion 8″ f/8 Ritchey-Chretien Astrograph Telescope, Teleskop Service (TS) 2.5” Rack and Pinon Focuser M90, Teleskop Service Flattener 1.0x for RC Telescopes (TS-RCFLAT2), Optolong L-Pro LP filter
- Imaging (Mills Rim, 30Dec2024): ZWO ASI2400MC imaging camera on (Big Bertha) Orion 8″ f/8 Ritchey-Chretien Astrograph Telescope, Teleskop Service (TS) 2.5” Rack and Pinon Focuser M90, Teleskop Service Flattener 1.0x for RC Telescopes (TS-RCFLAT2)
- Autofocuser: ZWO EAF Electronic Automatic Focuser – Standard (EAF-5V-STD)
- Mount: Rainbow Astro RST-300 (controlled by iHubo ASCOM driver)
- Polar alignment: QHYCCD camera (controlled by Polemaster for polar alignment)
- Autoguiding: Orion 60mm Multi-Use Guide Scope with Orion StarShoot AutoGuider Pro Mono Astrophotography Camera (controlled by PHD2)
Summary
Captured: Multi-session image; 1 December 2024 and 30 December 2024
Shooting location: HCH, Colorado Springs (1Dec2024) and Kiowa National Grasslands (30Dec2024)
Equipment: Big Bertha on Rainbow Astro RST-300
Processing summary: Captured in SGP, stacked in APP (Adaptive Airy), star removal with Starnet++, processing with LR/PS
Additional Images of SH2-261 Lower’s Nebula
Capture Notes
We cancelled our Thanksgiving trip to Cincinnati because of Zeus – he had been bitten by a horsefly who, apparently, had deposited a worm into his paw. On Monday afternoon (25Nov2024), before our Tuesday departure, he started limping, by Monday night he could barely walk, and when I got up early on Tuesday morning to take him for a trail walk before leaving for DEN, we discovered the bloody paw – and he would not walk more than a few feet before sitting or laying down. After cancelling the Cincinnati trip, we briefly thought about driving down to Albuquerque on Friday-Saturday. But then rethought that, and decided that since it was still a holiday weekend it would be better to just stay home. I suggested a dark skies trip, since both Comanche and Kiowa National Grasslands had clear skies forecast – that idea was vetoed, we weren’t ready and it was still a holiday weekend, it would be better to stay home. So, I decided to set up Big Bertha and capture some data from the front patio, so as not to completely forego the clear nights of and surrounding the New Moon.
I started the weekend’s imaging on Friday night (29Nov2024) with CTB1 Garlic Nebula, while I waited for SH2-308 Dolphin Head Nebula to rise at about midnight. The start (at 1824) and meridian flip (at 1930) both went well. But something shut down SGP after the last image was captured at 2154MST. The mount was still tracking and the laptop was still on, but none of the software was running, so no images were captured for the ~2 hours prior to the planned target swap at midnight. That marked the beginning of a week-long struggle with DSO-CTRL2 shutting down randomly in the middle of a sequence.
Sunday night (1Dec2024) again was clear, so I decided, even though it was a “school night,” to image to explore what was going on with the laptop. Sunday night again was clear, so I decided to image to explore what was going on with the laptop. NGC1491 Fossil Footprint was the first image of the evening. It ran for 3:12hrs and then the laptop shut down (Captured 1Dec2024, 1757 – 2109 MST). I picked up imaging with SH2-261 Lower’s Nebula at approximately 2200MST. Images were captured: 2206 – 0131MST; 0141 – 0553MST with the break being for the meridian flip. So, I thought that the towel I wrapped around the laptop and its case had done the trick to keep the laptop warm enough to operate correctly. (Spoiler alert – it was too much “dressing” and the cause of the random shutdowns was overheating – something I didn’t discover until we’d purchased DSO-CTRL3, configured it, and used it during our dark skies trip in late December!)
Sequence Plan (1Dec2024): Gain: 158, Temp: -0°C, offset=30. 85x300sec. Total: 425 minutes (7:05hrs). Total capture time: 1Dec2024, 2206 – 2Dec2024, 0553 MST. Images captured: 2206 – 0131MST; 0141 – 0553MST with the break being for the meridian flip.
Equipment
Equipment: All equipment controlled by DSO-CTRL2 HP Probook running Sequence Generator Pro v4.4.1.1441.
- Imaging (ASI2400-BB-FF-LPro): ZWO ASI2400MC imaging camera on (Big Bertha) Orion 8″ f/8 Ritchey-Chretien Astrograph Telescope, Teleskop Service (TS) 2.5” Rack and Pinon Focuser M90, Teleskop Service Flattener 1.0x for RC Telescopes (TS-RCFLAT2), Optolong L-Pro LP filter
- Autofocuser: ZWO EAF Electronic Automatic Focuser (EAF-5V-STD)
- Mount: Rainbow Astro RST-300 (controlled by iHubo ASCOM driver)
- Polar alignment: QHYCCD camera (controlled by Polemaster for polar alignment)
- Autoguiding: Orion 60mm Multi-Use Guide Scope with Orion StarShoot AutoGuider Pro Mono Astrophotography Camera (controlled by PHD2)
Summary
Captured: 1 December 2024
Shooting location: HCH, Colorado Springs, Colorado
Equipment: Big Bertha on Rainbow Astro RST-300
Processing summary: Captured in SGP, stacked in APP (Adaptive Airy), star removal with Starnet++, processing with LR/PS