Orion Season Targets + Comet

I've been looking forward to the appearance of comet C2022E3 ZTF's appearance in the northern sky near Ursa Minor. The late January Maryland weather has been iffy at best with mostly cloudy weather forecasts. Fortunately, on 1/27 the skies cleared despite a partly cloudy forecast and around 10:30 PM EST the comet was just high enough and clear of a neighbor's north blocking tree to catch the image below. Some light pollution from a nearby, poorly shielded street lamp managed to invade an otherwise dark sky background. Several to be revisited Orion Season DSOs also follow. 

Comet C/2022E3ZTF (1/27/2023)

NGC1579 Northern Trifid Nebula

NGC2264

M1-Crab Nebula

IC 410 

IC 405 Flaming Star Nebula

Happy 2023 from the Terrace

The condo association gave me an early Christmas gift cutting down the sky obscuring dying tree outside my terrace. Trees across the way still block my light polluted skies. Nonetheless, I now have a descent strip of sky between 20 and 45 degrees altitude to work with during Orion season. I'll still make trips to my favorite darkish site in Harvard, MA but this will cut down on my carbon footprint as well as freezing toes during winter months. An additional benefit is access to WiFi allows me to monitor the scope using Chrome remote desktop. I'm pleasantly surprised with NGC2359 acquired with 15s subs which I first imaged with 60s subs last April from the McCoy's landing darkish site.  I'll definitely revisit NGC2359 between now and April from the terrace. 

The experiment with finder only All Star Polar Alignment has worked better than expected. Typically, I have only needed the two alignment stars plus two calibration stars after rough alignment with Polaris which is not visible from my south facing terrace. Typically less than 2 degrees of azimuth and less than 1 degree of altitude correction have been needed to correct for axis deviation from polar alignment. Thus far the Celestron AVX GoTo puts targets in the NightOwl  field of view (FOV). To center faint targets I just use Precise Goto which puts a bright star in the field which when centered in the FOV and centers the target with an offset.  Below are targets acquired on 12/27/2022 using 60x15s or 120x15s exposures.  Update: M42 reprocessed for reduced contrast and saturation.

M77 Irregular Galaxy

NGC 1788 Reflection Nebula

Left to Right: NGC2024(Flame Nebula), NGC2023, Horsehead Nebula (B33)

NGC2359 (Thor's Helmet) -- To be revisited

Orion Nebula (M42) again 😂

A Few November DSO Captures

Celestron 8 SCT/ AVX  mount, Starizona NightOwl 0.4X Focal Reducer Corrector,

ASI294MC Pro. Typically 120x30s or 60x60s. Update: M2 reprocessed for 

better contrast.

Sharpless 142

Sharpless 170

Sharpless 155

NGC 7023

NGC 281 Pacman Nebula

M2

Alignment and Guiding Experiment

After setting up the telescope I usually do a Celestron AVX all star polar alignment (ASPA) using the visual finder for rough centering then fine centering on the computer screen with the ASI294MC Pro. I thought this might be bit of overkill considering the use of the Orion Magnificent Mini Autoguider. I setup the scope on my 3rd floor patio, as lousy a place for viewing considering no access to Polaris and a tree limited view. The ASPA was performed using the visual finder only starting with  rough north alignment. Jupiter, Saturn were used for alignment and Fomalhaut for calibration star. I usually use two alignment and four calibration stars in the field. Surprisingly only 7' altitude and 7' azimuth corrections were required. Pointing accuracy was less accurate than typical but was good enough to put target on the camera sensor. I had not checked the alignment of the finder with the optical train. This was good enough for M42 but not for NGC2023 so I used precision go to which uses a bright star as a waypoint to the faint target. M42 and NGC2023 with the Flame Nebula and Horsehead Nebula imaged that night appear below. Update: M42 reprocessed for reduced oversaturation.

M42

NGC 2023(center)with Flame Nebula(left) and Horsehead Nebula(right)

Update: A pleasant  start of Orion season surprise. Condo association removed twelve dead trees surrounding my building including the tree right in front of my terrace. Likely the association was prompted by the coming bomb cyclone that will hit Greater Boston with heavy rain and high winds. More sky!! 😀

No light pollution filter

For the first time since acquiring the Starizona Night Owl 0.4x focal reducer I decided to image with the Celestron F/6.4 focal reducer without a light pollution filter(LPF). These images were acquired in 14 to 15 radiance area in increasingly light polluted Frederick, MD vs the 0.5 to 1.0 radiance darkish areas where I image in Harvard MA and in Northern Maryland. Except for the NGC6946 which was imaged with 30s subframes all imaging was done with 15s subframes. I'll be revisiting many of my DSO favorites imaging without the LPF to see if an improvement in signal to noise can be achieved. Update: Globular clusters are reprocessed for less contrast and saturation.

Messier 13

Messier 15

Messier 27 

Messier 56

Messier 92

NGC6946

The Kit as the Brits Call It

I listen to lots of science podcasts while imaging, especially ones from the BBC, The Guardian and Nature; thus my kit comment. Above is the setup just after taking flat frames for the coming night session. Celestron 8, Celestron AVX mount, ZWO ASI294 MC Pro color camera, Starizona Night Owl 0.4x Reducer/Corrector and Orion Magnificent Mini Auto-guider, For power, partially hidden by tripod leg, a Westinghouse iGen160s. Also available a 12v Centech jump starter. During twilight the auto-guider is temporarily swapped for a 50mm visual finder to do the all star polar alignment. Then the auto-guider is swapped back in, wired up and calibrated using stars near the celestial equator.  Update: The Centech is no longer used. The  iGen160s has more than enough juice to handle all the night's power needs.

7-30-2022 Summer Favorites

All of these were acquired with 30s subs. NGC6946, NGC6888 and NGC6823 are averages of 120 subs while NGC6992 and NGC7635 are averages of 60 subs. NGC6823 is actually a new summer favorite that I will return to in the future. I'll be returning to NGC6946, NGC6888 and NGC6823 acquiring 60s subs in hope of bringing out more nebulosity or galaxy.

NGC6946 (Fireworks Galaxy)

NGC6888(Crescent Nebula)

NGC6823, NGC6820

NGC6992 (Eastern Veil Nebula)

NGC7635 (Bubble Nebula)