NGC 2237 - The Rosette Nebula (Skull Orientation)

This target was way too close to the nearly Full Moon ...

The night of February 20th was just a few days before The Full Moon (2/24). Even worse, this bright Moon was in the Constellation Gemini. This meant the Moon was very close to that night's target, The Rosette Nebula. Well, I wanted to see just how well the Optolong L-eXtreme Dual Narrowband filter would perform under these unfair circumstances. Spoiler alert, it wasn't great, but it wasn't a total loss.

I got home from work and setup my rig. As we are approaching spring, it is staying light noticeably later. This takes a little pressure off when getting setup (nothing worse than setting up under a clear dark sky). It still gets dark early enough to get a decent amount of imaging before it is too late. This will change as Spring turns towards Summer. I started collecting subs (short for sub-exposures) at 7:11 PM and stopped at 10:00 PM due to clouds. Exposure time was 180 sec each at Gin 100 / Offset 50 / -10 deg C. Ended up using 44 subs (2.2 hours total exposure) to produce the image. I oriented the object to show the Skull. Please note, there is a separate deep sky object called the Skull Nebula. My daughter is a Radiology Technician and has always had a fascination with bones, skeletons, and skulls. So, I guess this is in her honor.

NGC 2237 - The Rosette Nebula. Do you see the skull?

So, what about that Moon thing? Well, it was an issue. The image below is a single exposure (sub) with Boosted Auto Stretch applied. Thankfully we have many capable tools to deal with Gradients. No doubt this gradient impacted the processing of the image, but I'm pleased with how it ended up after processing. 

Single exposure showing Gradient from the Moon.

Processing:

I did all pre and post processing in PixInsight. Pre-processing: Blink & WBPP. Linear Post-processing: Dynamic Background Extraction (DBE - see next paragraph), BlurXTerminator (correct only), Spectrophotometric Color Calibration, BlurXTerminator, NoiseXTerminator, and Histogram Transformation. Non-Linear Post-processing: StarXTerminator. Starless: Narrowband Normalization (simulated SHO), Curves (Multiple iterations to increase brightness, contrast, and color saturation), SCNR, Local Histogram Equalization, Unsharp Mask, and Multiscale Median Transform. Stars: Curves (to increase color saturation) and SCNR. PixelMath was used to screen the stars back in. 

I tried two different methods of Gradient removal. Specifically, DBE, GraXpert, and the new Gradient correction process. To my eye DBE gave me the best result. GraXpert removed too much nebula and the new Gradient Correction Tool did not seem to work well with this image. Note: This is a new tool so it could also be that I did not apply it in the optimal manner.

What is it?

The Rosette Nebula contains multiple deep sky objects, including bright nebulosity and a star cluster (NGC 2244). NGC 2237 usually denotes the whole nebula. Other objects contained in the area include NGC 2238, NGC 2239, & NGC 2246. The nebula is in the constellation Monoceros. The Nebula has a circular pattern that resembles a flower. However, it can be oriented (as shown in my images) in a way that resembles a Skull. As indicated above there is an entirely separate deep sky object known as the Skull Nebula (NGC 246).

This object is an emission nebula. Stellar winds from the hot, large, and young stars in the star cluster have carved out the central area. These stellar winds also exert pressure on the remaining gas and dust. This leads to star formation, which is actively occurring in the nebula. 

How Big is it?

This object has an apparent size of 80 by 60 arcminutes (1 degree is 60 arcminutes) on the night sky. It is 128 light-years (ly) in diameter.

How Far is it?

It is located about 5,500 light-years (ly) from Earth in the Constellation Monoceros.

How to find it?

This object is easier to photograph than visually observe. To visually observe you will need requires dark skies and good seeing conditions, specifically transparency. A wide field telescope with a large field of view is required to see the entire object, as it is 5 times the size of the Full Moon in the sky. Large telescopes (over 8 inches) can reveal the dark nebulosity contained with the object.

Even though the constellation Monoceros is relatively dim, this object is relatively easy to locate. It is roughly halfway between the bright stars Betelgeuse (in Orion) and Procyon (in Canis Minor) as indicated in the finder chart below.

Image Details:

Capture Date: 02/20/2024

Location: Eden, NY

Telescope: Explore Scientific ED80 Essential Series Air-Spaced Triplet Refractor

Camera: ZWO ASI2600MC Pro

Filter: Optolong L-eXtreme

Mount: Sky-Watcher USA EQ6-R Pro

Exposure: 44 exposures at 180 sec / Gain 100 / Offset 50 / -10°C each for a total exposure of 2 hour and 12 minutes.

Software: NINA, SharpCap Pro, PHD2, and PixInsight

Clear Skies!

Ernie

M45 - The Pleiades

 The last in a recent string of clear nights ... but 1st a quick story:

A few years back my family was driving home from a family event on beautiful clear night. Someone remarked how beautiful the stars looked and my mother-in-law said, "oh yes, and you can really see the little Dipper!". I'm driving and trying to contain my inner Sheldon Cooper, we are driving south, there is no way she's talking about the Little Dipper. When we got home and parked the car, I asked her to show me. She pointed directly to the Pleiades. I realized it does in fact look like a min dipper. I politely explained what she was actually looking at and showed her how to find the actual Little Dipper. She was un-impressed. I don't think I ever consciously realized that M45 looks like a mini-dipper before (even though I have observed it for years). Now I often describe it in this way when describing it. Now back to your regularly scheduled blog post.

From Saturday 2/3/2024 through Tuesday 2/6/2024, we had a string of 4 clear nights. Skies weren't amazing, the transparency was not great, but the best opportunity for any astronomy related activity in 2 months or so. i got out to the observatory to image on 2/3/2024. Family and work obligations prevented me from imaging Sunday night or Monday night. Tuesday night was my last chance. The forecast was for clear skies early with the transparency turning poor/clouds around 11. Good news, it gets dark early enough to make imaging under worthwhile. Our Tuesday night imaging group was also in session. I joined from home via Zoom. 

After work, I quickly set up my scope. I had not used my home setup since October 3rd! I started collecting exposures at 7:04 PM. Since we were so close to New Moon, I decided on a broadband target, M45 (a.k.a. The Pleiades or Seven Sisters). Looking to improve on my initial result of this image from 2021. By 9:00 PM the transparency was starting to degrade. I kept imaging until 10:32 but had discard quite a most subs collected after 9:41 PM due to haze/thin clouds. Here's the resulting image. I'm pleased with result but hope to add data to this in the future, hope to pull out more of the faint background dust. 

M45, The Pleiades - from my backyard on 02/02/2024.

Showing the mini-dipper asterism. 

Processing:

All pre and post processing was performed in PixInsight. Pre-processing: Blink & WBPP (2x drizzle integration). Linear Post-Processing: GraXpert, BXT (correct only), SPCC, BXT, NXT, and HT. Non-linear Post-processing: StarXT. Stars: Curves (saturation) and SCNR. Starless: Curves (multiple for brightening, contrast, and saturation), SCNR, LHE (3 kernel sizes), Unsharp Mask, MMT, & PixelMath (to screen stars back in). Integer Resample was used to down sample the image. 

What is it?

Messier 45 is probably the most famous Open Star Cluster in the night sky. It is easily visible to the naked eye. The brightest 6 stars form a distinctive mini-dipper pattern not far from Orion. It is known by many names by different cultures around the world. If you drive a Subaru, look at the logo. Subaru ids the name for M45 in Japan. The cluster contains over 1,000 confirmed stars. The reflection nebula that surrounds the cluster is not associated with the cluster. The cluster is just passing through it and the starlight from the cluster is reflecting it, in the same way our atmosphere scatters the light from the Sun making our sky appear blue. 

Annotated version of the image of M45.

How big is it?

This object has an apparent size of 12 arcminutes (1 degree is 60 arcminutes) on the night sky. It is 16 light-years (ly) in diameter.

How far is it?

It is located about 440 light-years (ly) from Earth in the Constellation Taurus.

How to find it?

This object is easily visible to the naked eye. You won't see the beautiful reflection nebula, but the 6 brightest stars are quite bright and form a very recognizable mini-dipper pattern (asterism). It is not far from the V-shaped Hyades in Taurus. Start with the belt stars in Orion. Starting from the lowest star (Alnitak), extend through the highest star (Mintaka) for about 35 degrees (about 3-1/2 fists). Refer to the finder charts below.

How to use Orion's Belt to find M45.

A finder chart for M45 with a tighter field of view.

Image Details:

Capture Date: 02/06/2024

Location: Eden, NY

Telescope: Explore Scientific ED80 Essential Series Air-Spaced Triplet Refractor

Camera: ZWO ASI2600MC Pro

Filter: none

Mount: Sky-Watcher USA EQ6-R Pro

Exposure: 66 exposures at 120 sec / Gain 100 / Offset 50 / -10°C each for a total exposure of 2 hour and 12 minutes.

Software: NINA, SharpCap Pro, PHD2, and PixInsight

Clear Skies!

Ernie

Experimenting at the Club's Observatory

 First off, it's been a while ... 

The last clear night that I was able to image was on October 3rd. So, apologies for taking so long between posts. The weather has been horrendous and travel for work forced me to miss the one clear night we had in November. I was super excited to see a clear forecast for Thursday night (December 14th). Our astronomy club has an imaging group, we're called the Tuesday Night Imagers. the leader of our group posted on the forum of our website that Tuesday would be Thursday this week. One advantage of winter is I can make it out to the observatory after work and get a few hours of imaging in and still get home at a reasonable time. 

We made our plans ahead of time. The plan was to try my personal camera, the ZWO ASI2600MC-Pro on the club's Celestron 14" Edge D Telescope. Our club has the 14" and a Tele Vue NP-101is mounted on an Astro Physics AP-1200 mount. We have an Atik 383L+ Color camera for the 14". A great camera, but it is an older CCD camera and is starting to show it's age. We are actively discussing what camera to get to replace it. We wish to stick with a One-Shot Color (OSC) camera for simplicity and convivence. Technically, my camera is a great match for the NP-101is but not for the 14". Even with the 0.7x focal reducer, the 14" has focal length of 2,738 mm. Therefore, my camera's small pixels result in a very over-sampled image scale with the 14". This is typically not desirable. However, we have seen some great results from similar setups and decided to give this a try. 

I got to the observatory around 5:30 pm. The observatory director, the leader of our imaging group, was unable to make it out to the observatory due to a last minute issue. Typically, the observatory director and another member of our group are the main operators of the telescope. The other telescope operator and I got the telescopes going. My camera on the 14" and the other telescope operator put his ZWO ASI1600MC-Pro on the NP-101. The observatory director and a couple of other members of our imaging group joined us via Zoom. 

The skies were not great. lots of high/thin clouds or haze especially towards the western horizon. Of course, that's exactly where we wanted to image. We wanted to get data on Comet 12/P Pons-Brooks which is near the bright star Vega. We tried for about an hour, but the data was not looking good. Autofocus was struggling and there was little signal from the comet. I have not tried to process the data from the 14" yet but the other telescope operator managed to get a nice image (especially considering the conditions). 

As it was also the peak of the Geminids meteor shower, we did try to get outside and see if we could see meteors. We saw about four or five. We also noticed skies were better towards the Southeast, where the constellation Orion was rising. We decided to give up on the comet and slew to the Horsehead Nebula (Barnard 33). We slewed to B33 and got both telescopes framed as best as we could. We were feeling the pressure to get imaging quickly, so we didn't rotate the camera or refine (manually) the relative pointing of the telescopes to one another, a disadvantage of two scopes on one mount. We dialed in our exposure settings, 120 sec subs at Gain 100 with an Offset of 50 for me and started collecting exposures. The results looked really good. The stars were nice and round. We imaged for little over an hour. It was a work night, skies weren't the best, and both of us had a pretty good drive home. This is the resulting image from the night's work. Pretty encouraging results!

The Horsehead Nebula (B33) from the BAA's Beaver Meadow Observatory on 12/14/2023.

Processing

There was a lot of conversation in our club's forum leading up to Thursday night and again afterwards regarding how to capture and process images with this scope/camera combination. We are lucky to have some talented imagers in the group, one in particular who is both very talented and technically knowledgeable. This person was a key participant in those discussions and I'm personally very grateful for his mentoring.

All pre and post processing was performed in PixInsight. Pre-processing: All 34 images were examined in Blink, 2 were rejected. The remaining 32 images were calibrated, registered, and stacked in WBPP with 1X Drizzle integration, astrometric solution, and auto-crop enabled. 

Linear Post-processing: Gradient was removed with the GraXpert script (AI mode), initial deconvolution with BlurXT in Correct Only mode, color calibration SPCC, second deconvolution with BlurXT, noise reduction NoiseXT, and the image was made non-linear with HT. Non-linear Post processing: Stars were removed with StarXT. Stars: Saturation curve applied with CT and green noise removed with SCNR. Starless: Multiple iterations of CT were applied to increase brightness and contrast, Saturation was added with CT, green noise was removed with SCNR, and noise reduction was further reduced with NoiseXT. The image was sharpened with LHE at 3 different kernel sizes and MMT. Dark structure was enhanced with the DSE script and stars were screened back in with Pixel Math. No down sampling was performed. 

What is it?

The Horsehead Nebula (Barnard 33) is a small dark nebula silhouetted against the emission nebula IC434. B33 resembles the profile of the head of a horse. It is a concentration of dust and non-luminous gas that blocks light of the nebula behind it. 

Annotated image of the Horsehead Nebula

How big is it?

This object has an angular distance of 6.0 x 4.0 arcminutes on the night sky. The object is 2.8 light-years (ly) across. 

How far is it?

It is located about 1,600 light-years (ly) from Earth in the Constellation of Orion.

How to find it?

It is located close to Alnitak, one of the 3 belt stars in Orion. This makes it easy to find. However, it is much easier to photograph than visually observe. To give you the best chance of success in visually observing it, use a large aperture telescope, use an H-beta nebula filter, and get to dark skies. It is tiny and it is essentially like trying to find a black fingerprint on a black tablecloth. Try to find the emission nebula IC 434 and look for the absence of the nebula. Photographically, this target shows up relatively easily and can be captured with and without the use of filters. 

Finder Chart for B33

Image Details:

Capture Date: 12/14/2023

Location: North Java, NY (BAA's Beaver Meadow Observatory

Telescope: Celestron 14" Edge HD w/0.7x Focal Reducer

Camera: ZWO ASI2600MC Pro

Filter: N/A

Mount: Astro Physics AP-1200

Exposure: 32 exposures at 120 sec / Gain 100 / Offset 50 / -10°C each for a total exposure of 1 hour and 4 minutes.

Software: NINA, PHD2, and PixInsight

Clear Skies!

Ernie

NGC 6888 -The Crescent Nebula

 Attack of The Floating Space Brain!!!

Tuesday October 3rd was forecast to be our last clear night for about 2 weeks. Even though it was a work night, decided I had to get out and image something. Fortunately, the Sun is setting earlier, which means we can get some time on targets before it gets too late. Unfortunately, the 82% illuminated Moon would rise around 9 PM. Therefore, I decided to image a bright narrowband target using my L-eXtreme Dual Narrowband filter. The target selected was NGC 6888, The Crescent Nebula. I see a floating space brain. Perhaps I've watched too much sci-fi.

NG6888 - The Crescent Nebula captured on 10/3/2023. Can you spot the Soap Bubble Nebula?

As soon as I got home from work, I set up the telescope. Once it was dark enough, the scope was polar aligned and PHD2 was calibrated. The sequence, created ahead of time, was initiated and the first sub was taken at 8:19 PM. Tuesday night also happened to be the night our astronomy club's (Buffalo Astronomical Association) imaging group was in session. We are called the Tuesday Night imagers (even though we don't always meet on Tuesday). I was imaging from my backyard, so I joined the group at the observatory via Zoom. One of our members advised that I don't need to calibrate PHD2 every time I setup once I have a good calibration. will have to give this a try next time. Will save a little time setting up. May only need to redo calibration if my setup changes. 

I imaged until just a few minutes past midnight, as I would be losing the target to the trees. The Sequence was timed nearly perfectly, the last sub showed a small shadow from the tree. I was already asleep, NINA parked my mount and warmed up the camera. I got up early to retrieve my laptop and put my telescope in the shed. A total of 65 subs were captured at 180 seconds each (Gain 100 / Offset 50).

Processing:

All pre and post processing was performed in PixInsight. Images were reviewed with Blink and the Subframe Selector Process, with a total of 10 images rejected. The 55 remaining subs were loaded in WBPP. Astrometric solution, Autocrop, & 2X Drizzle integration were enabled. Linear: The background was removed with ABE and color calibration was performed with SPCC. The image was deconvolved with BlurXT, noise was reduced with NoiseXT, and the image was stretched with HT. 

Non-linear: The stars were removed with StarXT and here's where things get a little interesting. As a result of a conversation on the Zoom, I decided to try the Narrowband Normalization Process (Cosmic Photons) from Bill Blanshan and Mike Cranfield. Specifically, I used the HOO palate (no choice as i was using a dual narrowband filter with an OSC camera) in Blend 2 mode. This process is amazing (as my friend had indicated in our conversation). The Realtime Preview, sliders, and various selections make it easy to get the best results for your image! Stars: Applied saturation with CT, removed green noise with SCNR, and ran the Correct Magenta Stars script. Starless: Applied multiple iterations of CT to add saturation, increase brightness, and contrast. Applied LHE at 3 different kernel sizes. Applied MMT and DSE. I screened the stars back in with Pixel Math and did some star reduction with Bill Blanshan and Mike Cranfield's Star Reduction process. Finally, the image was down samples to a more manageable size.

What is it?

The Crescent Nebula (NGC 6888) is an emission nebula located in the constellation Cygnus. This object is formed by the strong stelar wind from a Wolf-Rayet star (WR 136). This star is losing its outer layers at the rate of the mass of our Sun every 10,000 years. This massive star is likely to go Supernova some day in a million or so years.

Annotated image of NGC 6888.

How big is it?

This object has an angular distance of 20 x 10 arcminutes (1 degree is 60 arcminutes) on the night sky. The object is 25 light-years (ly) across. 

How far is it?

It is located about 4,700 light-years (ly) from Earth in the Constellation Cygnus.

How to find it?

This object is relatively easy to find. It's very close to the bright star Sadr in the constellation Cygnus. Refer to the finder chart below. 

Finder Chart

Image Details:

Capture Date: 10/03/2023

Location: Eden, NY

Telescope: Explore Scientific ED80 Essential Series Air-Spaced Triplet Refractor

Camera: ZWO ASI2600MC Pro

Filter: Optolong l-eXtreme 

Mount: Sky-Watcher USA EQ6-R Pro

Exposure: 55 exposures at 180 sec / Gain 100 / Offset 50 / -10°C each for a total exposure of 2.75 hours.

Software: NINA, SharpCap Pro, PHD2, and PixInsight

Clear Skies!

Ernie

LDN 1235 - The Dark Shark Nebula

 Smile you Son of a ...

LDN 1235 - The Dark Shark Nebula captured on 9/14/2023 & 9/15/2023

This never happens!!! Two clear nights in a row at New Moon!!! Thursday (9/14) and Friday (9/15) were predicted to be clear, with no Moon. Therefore, wanted to go after something that was a challenge or stretch target for me and my Bortle 4/5 location, The Dark Shark Nebula. This target is very faint and requires dark skies and lots of exposure. I have pretty good skies, around Bortle 4 or 5, darker skies would be better, but figured I would give it a go. 

Wednesday, I framed up the image using Telescopius (telescopius.com) because I wasn't able to find this object in the NINA Sky Atlas. One advantage of Telescopius is that it allows you to adjust the brightness of the image being displayed. Increasing the brightness made the Shark visible, an advantage when framing the image. I imported the coordinates into the NINA Framing Assistant and then created a Sequence so I would be ready to go Thursday night. I still use the Legacy Sequencer, although I'm preparing to give the Advanced Sequencer a try. Will use a night with a bright Moon to experiment (not risking clear nights at New Moon). 

Thursday, after getting home from work, I quickly set up my imaging rig. Things went smoothly. Polar aligned with SharpCap Pro and calibrated the guiding software (PHD2) once skies were dark enough. Started collecting subs at 8:43 PM. Individual 2-minute sub exposures (subs) did not show any hint of the Shark, even with a screen stretch. I decided to keep collecting exposures without a change because I was shooting to the North, there's lots of light pollution to my North. Examining the subs and looking at the histogram led me to the decision to keep exposure as is. My hope was by getting enough exposures, I would be able to get the Shark. I stopped imaging at 2:23 AM, when the target would be lost to the trees. Was able to collect 130 subs on night 1. NINA parked my scope and warmed the camera. I got up earlier the next morning to bring in my laptop and cover my rig with a tarp. 

A single 2-minute exposure (calibrated and debayered) with an unlinked auto stretch applied (no other processing). Do you see the Shark? 

I got a later start on Friday night as I tried (unsuccessfully) to catch Comet C/2023 P1 Nishimura at sunset. Started capturing exposures at 8:54 PM. Conditions were very good again and the imaging session went smoothly. The session ended at 2:31 AM. A total of 139 exposures were captured. NINA parked the scope and warmed the camera. Retrieved my laptop in the morning and waited until late morning to put my equipment away, as everything was covered in dew. Saturday was forecast to be cloudy. Even if it was clear, I would not have been able to image due to family a commitment. 

Image Processing

All pre and post processing was done in PixInsight. All 269 sub exposures were evaluated with Blink and the Subframe Selector process. After this evaluation, 36 sub exposures were discarded. The remaining 233 subs were loaded into the Weighted Batch Pre-Processing Script (WBPP) along with the associated calibration (Darks, Flats, & Flat Darks) frames. This represents a total of 7 hours and 46 minutes of total exposure. I enabled 2X Drizzle Integration. This is the resulting Master Light unlinked auto stretch applied (no other processing). 

Master Light from WBPP. Can you start to see the Shark now?

Linear Processing: Automatic Background Extraction (ABE), Sprectrophotometric Color Calibration (SPCC), RC-Astro's BlurXTerminator (BXT), RC-Astro's NoiseXTerminator (NXT), and the image was made non-linear with Histogram Transformation (HT). 

Non-Linear Processing: RC-Astro's StarXTerminator (SXT). Stars: Saturation was enhanced with Curves Transformation (CT) and Green Noise was removed with SCNR. Starless: Another application of NXT, the Image was brightened, and contrast was enhanced with multiple applications of CT. A mask was applied, and Saturation was enhanced with CT. Mask was removed and SCNR was applied. Local Histogram Equalization (LHE) was applied at 3 different Kernel sizes followed by Multiscale Median Transform (MMT). Dark Structure Enhance script (DSE) was used and the Stars were screened back in with pixel Math. The image was resampled down by 50% with the Resample process (making the file size a little more manageable). The image was processed 6 different times using the above process/scripts with slightly different setting each time, until the final (for now) image at the beginning of this post was obtained.  

What is it?

The Dark Shark is located in a section of the Milky Way that contains a lot of interstellar Dust and Gas. This object is comprised of interstellar dust and gas. Powerful winds radiating from massive stars create the "structure" or shape of this object. 

An annotated version of the image

How big is it?

This Shark is about 15 light-years (ly) from head to tail.

How far is it?

It is located about 650 light-years (ly) from Earth in the Constellation Cepheus.

How to find it?

I'm honestly not sure if this object can be observed visually, if it can be observed, assuming this would be a very challenging target. My gut says this can't be visually observed. This object is located in the Constellation Cepheus. To me, it looks like a house. The Dark Shark Nebula is location is indicted by the red rectangle in the finder chart below. 

Finder Chart for Dark Shark Nebula

Image Details:

Capture Date:09/14/2023 and 09/15/2023

Location: Eden, NY

Telescope: Explore Scientific ED80 Essential Series Air-Spaced Triplet Refractor

Camera: ZWO ASI2600MC Pro

Filter: None

Mount: Sky-Watcher USA EQ6-R Pro

Exposure: 9/14: 104 exposures at 120 sec each; 9/15: 129 exposures at 120 sec each for a total exposure of 7 hours 46 minutes. Gain 100 / Offset 50 / -10°C for both nights.

Software: NINA, SharpCap Pro, PHD2, and PixInsight

Clear Skies!

Ernie

M27 with a Dual Narrowband Filter

A return to M27

Friday September 1st was a clear night, a clear night with a very bright (nearly full) Moon. I decided to use my Optolong L-eXtreme dual narrowband filter on M27. I imaged M27 without a filter under moonless skies back in May (click here for the related post). The L-eXtreme has 7 nm band passes in both Ha and Oiii. It would be interesting to see how it would perform with an almost full Moon. This is the resulting image.

M27 imaged with a dual narrowband filter on 9/1/2023.

Setup went relatively smoothly. Started collecting images at 9:14 PM and stopped at 1:56 PM when clouds started to roll in (I wouldn't have been long until I lost the target to the trees anyways). I collected a total of 52 subs at 300 sec each. All pre and post processing was performed in PixInsight. A total of 45 subs were used after inspecting the frames with blink and using the Subframe Selector process. Processes used: Blink, Subframe Selector, WBPP (enabled2x Drizzle Integration and Autocrop), DBE, SPCC, BlurXTerminator, NoiseXTerminator, HT, and StarXterminator (unscreen stars). Stars: Curve Transformation (saturation), SCNR, and Correct Magenta Stars Script. Starless: Curve Transformation with mask (RGB/K), Curves Transformation with mask (saturation), SCNR, LHE, MMT, and Pixel Math to Screen stars back in. Finally, the image is significantly cropped in as this object is very small in my setup.

What is it?

Messier 27 (M270, also known as the Dumbbell Nebula, is a form of Emission Nebulae known as a Planetary Nebula. It has the distinction of being the first planetary Nebula ever discovered.  A Planetary Nebula is the remnant of a star, like our Sun, that is too small to end its life as a Supernova. Instead, as the star reaches the end of its life, no longer capable of fusion, the star will lose its outer shells. A hot and very dense remnant known as a White Dwarf is left behind. Even though it is no longer capable of fusion, it is hot enough to ionize the expelled shells of gas.

How big is it?

This object has an angular distance of 8.0 x 5.7 arcminutes (1 degree is 60 arcminutes) on the night sky.

How far is it?

It is located about 1,400 light-years (ly) from Earth in the Constellation Vulpecula.

How to find it?

This object is relatively easy to find in a pair of binoculars, optical finder scope, or telescope with a wide field of view. It is located in the Constellation Vulpecula which is a dim constellation located within the Summer Triangle. A nebula filter (like UHC or Oiii) filter can help improve contrast and make the nebula stand out more from the background sky. Use the finder chart below to help you locate it.

1. Find the Summer Triangle (Vega, Deneb, & Altair).
2. Method 1: 
1. Find Albireo (a beautiful visual target itself) which is the head of Cygnus the Swan or the base of the Northern Cross. 
2. Find Altair. 
3. M27 is the vertex of a imaginary triangle with Albireo and Altair as the other two vertices.
3. Method 2: (Darker skies may be required)
1. Find 13 Vulpeculae.
2. Find Gamma Sagittae.
3. M27 is the vertex of a imaginary triangle with 13 Vulpeculae and Gamma Sagittae as the other two vertices.

Finder Chart for M27

Image Details:

Capture Date:09/01/2023

Location: Eden, NY

Telescope: Explore Scientific ED80 Essential Series Air-Spaced Triplet Refractor

Camera: ZWO ASI2600MC Pro

Filter: Optolong l-eXtreme 

Mount: Sky-Watcher USA EQ6-R Pro

Exposure: 45 exposures at 300 sec / Gain 100 / Offset 50 / -10°C each for a total exposure of 3.75 hours.

Software: NINA, SharpCap Pro, PHD2, and PixInsight

Clear Skies!

Ernie

IC 1396 - The Elephant Trunk Nebula - 07/07/2023

 It was an unexpected clear night and a Friday night too!

Clear skies on a Friday night and daylight savings time actually working to my advantage. Noticed potential for clear skies that morning of July 7th but didn't get my hopes up too high. Got home from work, went to dinner, ran a few errands, and got home in plenty of time to setup before dark. Since the Moon was going to rise at midnight, figured it would be good to after an emission nebula so I could try out my L-eXtreme Dual Narrowband filter out with my ZWO ASI2600MC Pro for the first time. Got great results with the filter last year with my DSLR. I decided to shoot IC 1396, The Elephant Nebula in the constellation Cepheus. 

Started capturing 180 sec subs at 10:18 PM and kept going until 4:06AM, when I went outside to take flat frames. Ended up using 79 subs, resulting in a total exposure of 3.95 hours. The image was processed in PixInsight using a Dual Narrowband "SHO" method that was provided to me by a mentor from the Buffalo Astronomical Association. This method approximates the SHO or Hubble Palette color map scheme with data from dual Narrowband filters and one-shot color (OSC) cameras like mine. 

This is the resulting image. 

IC1396 - The Elephant Trunk Nebula from 07/07/2023

What is it?

IC 1396 is a region of ionized interstellar gas and dust that contains smaller regions of concentrated gas and dust that appear as dark knots or globules in visible light images. The gas in the entire region is being ionized by the bright star HD 206267 in the center of the image. The Elephant Trunk Nebula is one of those concentrations of gas and dust. It can be seen rising from the bottom of the image. These areas of concentrated gas and dust, including The Elephant Trunk, are star forming regions. Young stars within The Elephant Trunk were discovered in 2003 using infrared telescopes.

An annotated image of IC 1396, The Elephant Trunk Nebula.

How big is it?

The entire region is hundreds of light years across and spans over 3 degrees on the night sky.

How far is it?

IC 1396 is located about 2,400 light-years (ly) in the Constellation Cepheus.

How to find it?

The constellation Cepheus is located near the bright signpost constellation Cassiopeia. Cepheus is a circumpolar constellation for observers at mid-northern latitudes and above. This means the constellation never sets. It is visible all night, appearing to circle the north celestial pole currently located near the North star, Polaris. to me, this constellation looks like a house with disproportionately large roof. IC 1396 is indicated in the chart by the red rectangle just off what would be the ground floor of the house. 

Finding Chart for IC 1396 (the red rectangle in the center of the chart).

Image Details:

Capture Date:07/07/2023

Location: Eden, NY

Telescope: Explore Scientific ED80 Essential Series Air-Spaced Triplet Refractor

Camera: ZWO ASI2600MC Pro

Filter: Optolong l-eXtreme 

Mount: Sky-Watcher USA EQ6-R Pro

Exposure: 79 exposures at 180 sec / Gain 100 / Offset 50 / -10°C each for a total exposure of 3.95 hours.

Software: NINA, SharpCap Pro, PHD2, and PixInsight

Clear Skies!

Ernie

Markarian's Chain

 A great Galaxy Season target for widefield setups

Those of us with shorter focal length, widefield setups can feel target starved during galaxy season. Galaxies, with a few exceptions, are often small targets, better suited for longer focal length telescopes. Markarian's Chain is a string of galaxies located in the constellation of Virgo, that makes an aesthetically pleasing target for telescopes with a wide field of view. My imagination sees this string of galaxies as a snake like creature with an oversized head sporting a "meh" expression. 

Markarian's chain captured from my backyard on May 15, 2023.

The chain of galaxies includes M86 and M84 as well as a pair of interacting galaxies, NGC 4438 and NGC 4435, known as The Eyes. Not sure why they are called The Eyes, but I see M86 and M84 as a pair of eyes. The prominent elliptical galaxy located in the lower left corner of the image is M87. Please refer to the annotated image below to identify the prominent galaxies contained in this field of view. Please note, this annotation was limited to NGC and IC catalogs, as the resulting annotated image would be overwhelming due to the number of galaxies in this field if other catalogs were included. 

Annotated image of Markarian's Chain. Note: annotation limited to NGC and IC catalogs.

The data for this image was captured on the night of May 15, 2023. The imaging session began at 9:52 PM and was completed at 2:21 AM on the morning of the 16th, when the target was lost to the trees. A total of 102 120 sec sub exposures were captured, of which 65 were used to produce the image. If become more discriminating about the exposures I use to produce images. I use the Blink process and the "SubframeSelector" process in PixInsight to remove exposures with undesirable characteristics (poor focus, eccentric stars, low signal weight, etc...) due to various factors like passing clouds. I have found being more discriminating about the individual subs for the image has been producing better results. This is my third attempt at processing this data. Since we have not had any good conditions for imaging since late May, I have had plenty of time to process data lurking in my hard drive.

What is it?

Markarian's Chain is a string of galaxies located in the constellation of Virgo that forms part of the Virgo Cluster of galaxies. The chain of galaxies is named after soviet astrophysicist, Benjamin Markarian, who discovered that at least seven of the galaxies in the chain move coherently. 

How big is it?

The field of view of this image is roughly 2.8 degrees by 1.9 degrees. 

How far is it?

The prominent galaxies in this image (M84, M86, and The Eyes) are located about 50 million light-years (50Mly) from Earth.

How to find it?

Unfortunately, as the publishing of this post, Markarian's Chain can be found low in the western sky. This target is best viewed during spring in the northern hemisphere. Markarian's Chain is located in the "bowl" of the constellation Virgo. Refer to the finder chart below. I use the two stars at the top of the bowl and Denebola, the star that marks the tail of Leo the Lion, to triangulate its position. 

Finding Chart for Markarian's Chain.

Image Details:

Capture Date:05/15/2023

Location: Eden, NY

Telescope: Explore Scientific ED80 Essential Series Air-Spaced Triplet Refractor

Camera: ZWO ASI2600MC Pro

Filter: None

Mount: Sky-Watcher USA EQ6-R Pro

Exposure: 65 exposures at 120 sec / Gain 100 / Offset 50 / -10°C each for a total exposure of 2.2 hours.

Software: NINA, SharpCap Pro, PHD2, and PixInsight

Clear Skies!

Ernie

3rd Object from "Supernova Week" - M27

Messier 27 - The Dumbbell Nebula

The week of 05/21/2023 was a fantastic week for imaging. Not only did I capture multiple nights SN 2023ixf in M101 (click here) and The Iris Nebula (click here), I was also able to capture two other targets. On the night of 05/24/2023 (actually the morning of 05/25/2023) I imaged Messier 27, The Dumbbell Nebula after losing M101 to a tree somewhere around 1:30 AM. Sky conditions were very good, so I slewed to M27 and imaged until the end of Astronomical Dark (2:04 AM to 3:35 AM). 

An image of M27 captured on 05/25/2023. This target is quite small for my imaging setup, so the image is cropped in significantly. 

I'm pretty happy with the way this turned out. After watching RC-Astro's Russ Croman on The Astro Imaging Channel (TAIC), I used his MTF Analyzer to analyze my setup. According to the tool, I'm slightly under-sampled and would benefit from using 2X drizzle integration. I tried it and I think it was worthwhile. M27 is a very small target for my set up (480 mm refractor with APS-C sensor). Therefore, the image presented here has been cropped in significantly. 

What is it?

Messier 27 is a planetary located in the constellation Vulpecula. M27 is the first Planetary Nebula ever discovered. A Planetary Nebula is an emission nebula formed from an expanding shell of ionized gas ejected by stars (like our Sun) too small to go supernova when they (stars) are late in their lives. A stellar remnant known as a White Dwarf is left behind and is responsible for ionizing the gas. M27 is a popular target for amateur astronomers as it is visible in binoculars and telescopes. 

How big is it?

It has an angular size of 8 x5.7 arcminutes on the night sky and has a diameter of about 3.2 light-years. 

How far is it?

The M27 is within the Milky Way at about 430 parsecs (pc) or 1,400 light-years (ly) from Earth.

How to find it?

M27 is a popular target for visual astronomers. A nebula filter (like a UHC or OIII filter) can really help make it pop visually. M27 is located within the Summer Triangle. 

Refer to the finder chart below. 

1. Find the Summer Triangle (Vega, Deneb, & Altair).
2. Locate the star Albireo (the head of Cygnus the Swan).
3. Rough location method:
1. Using the finder Chart below, M27 is one vertex of an imaginary triangle with the other vertices Altair & Albireo. 
4. If you have dark enough skies to see the constellations Sagitta (actually looks like an arrow) and Vulpecula, you can use the finder chart below to refine the position of M27.

Finder chart for M27.

Image Details:

Capture Date:05/24/2023

Location: Eden, NY

Telescope: Explore Scientific ED80 Essential Series Air-Spaced Triplet Refractor

Camera: ZWO ASI2600MC Pro

Filter: None

Mount: Sky-Watcher USA EQ6-R Pro

Exposure: 60 exposures at 60 sec / Gain 100 / Offset 50 / -10°C each for a total exposure of 1 hour.

Software: NINA, SharpCap Pro, PHD2, and PixInsight

Clear Skies!

Ernie

Reflection in the Dark - The Iris Nebula

 It was a really good week for astrophotography!

Starting on the night of Sunday May 21st through Friday May 26, we had a great stretch of weather for astrophotography, at least as far as Western New York is concerned. Sunday and Monday were impacted by smoke from the wildfires in Alberta, Canada. Even with the smoke, I managed to capture data on SN 2023ixf in M101 (click here). Wednesday, Thursday, & Friday had better conditions. Being able to leave my scope setup all the way through Saturday (extremely rare for our area).

On Wednesday night I started the evening on SN2023ixf in M101 and then moved to another target (post coming soon) as I lose M101 in a tree around 1:30 AM. Not wanting to squander the clear skies I added a sequence for second target to NINA. Technically this was the morning of Thursday May 25th since it was after midnight. However, that's not how I think about it and organize my files. I started the imaging session on the night of Wednesday May 24th and carried that date through sunrise. That's the convention I follow, right or wrong. 

On Thursday, the Moon was setting around 1:30 AM. Thought I would try for the Iris Nebula. This target is something I've wanted to image for a while, but avoided as I considered it more of an "advanced" target. As my skills have been progressing, thanks to experience, mentors in the BAA, and knowledge/skill gained form Masters of PixInsight classes, I decided to give it a shot. glad I took the chance. On Friday I did not image M101, just felt like trying something different. I didn't want to go to the Iris right way because the Moon was brighter and wasn't going to set until 1:52 AM. So imaged another target (post coming soon) until 1:30 am and then switched back to the Iris. I think Thursday night was the best night of the week. 

The image was processed in PixInsight. It took multiple attempts to get this result, but I'm really pleased with it. Still a little unsure (due to inexperience with dust and dark nebulae surrounding the reflection nebula) I posted it on Twitter and asked for feedback. The feedback was very positive. I also shared the image with members of the imaging group within the BAA. Again, the feedback was positive. 

For the first time since I started imaging with this Deep sky setup, the hard drive on my imaging laptop was nearly full by the end of the week. Will need to consider upgrading the storage on the laptop. This was an unusual problem to have as we almost never get that many good nights so close together. It was a really fun week chasing the supernova in m101 and imaging the Iris and the other targets I went after. Very reminiscent of chasing Comet Neowise in 2020. I hope you enjoy the image.

The Iris Nebula (NGC 7023 / LBN 487) captured on 05/25/2023 & 05/26/23.

What is it?

The Iris Nebula is a fairly bright reflection nebula in the constellation of Cepheus. The reflection nebula is surrounded by lots of dust. The Iris Nebula is also known as NGC 7023, Caldwell 4, and LBN 487. Unlike emission nebulae, reflection nebulae do not emit their own light. The color comes from scattered light of its central star. Reflection nebulae are made up of very small particles, much smaller than dust particles on Earth. these particles scatter light giving the nebula its bluish color (similar to our sky).

An annotated image of the Iris Nebula and surrounding dust. 

How big is it?

It has an angular size of 18 x 18 arcminutes on the night sky and is about 6 light-years across. 

How far is it?

The Iris Nebula is within the Milky Way at about 420 parsecs (pc) or 1,400 light-years (ly) from Earth.

How to find it?

This object can be observed visually as well as being a popular photographic target. Dark skies are a must. 

Refer to the finder chart below. 

1. Find Cassiopeia with its distinctive "M" or "W" shape.
2. Find Polaris (the North Star).
3. Find Cygnus or the Northern Cross. 
4. The constellation Cepheus looks like a house and is located between items 1,2, & 3.
5. The Iris Nebula is within the red box on the finder chart (the red box indicates the field of view of the image.

 

A finder chart for the Iris Nebula.

Image Details:

Capture Date:05/25/2023 and 05/26/2023

Location: Eden, NY

Telescope: Explore Scientific ED80 Essential Series Air-Spaced Triplet Refractor

Camera: ZWO ASI2600MC Pro

Filter: None

Mount: Sky-Watcher USA EQ6-R Pro

Exposure: 5/25/: 60 exposures at 120 sec each; 5/26: 50 exposures at 120 sec each for a total exposure of 3.67 hours. Gain 100 / Offset 50 / -10°C for both nights.

Software: NINA, SharpCap Pro, PHD2, and PixInsight

Clear Skies!

Ernie

Chasin' SN 2023ixf in M 101

A star went BOOM!

About 21 million years ago in the galaxy Messier 101, the Pinwheel Galaxy, a star went boom. It really went boom. Specifically, a Core Collapse Supernova known as a Type II Supernova, one of the most energetic events in the Universe. This particular supernova was first observed on May 19, 2023, by Koichi Itagaki. The Zwicky Transient Facility confirmed the discovery and found an image of the supernova (much fainter) from two days before the discovery observation. 

A recent image of M 101 from before the supernova. 

Type II Supernova Facts

• This type of supernova occurs for stars at least 8 times more massive than our Sun and will leave behind a Neutron Star or Black Hole. 
• Supernovae can outshine their host galaxies, releasing as much energy in a single burst as our Sun will release in 10 billion years. 
• Many of the elements heavier than iron are created in this type of Supernovae.
• Supernovae produce a mind bogglingly large number of Neutrinos. In 10 seconds a core-collapse supernova will release 10⁵⁸ neutrinos.
• Supernovae can accelerate particle to at least 1000 times the energy of particles in the Large Hadron Collider. 

Good Timing

The timing of this event was favorable for observation by amateur astronomers in the northern hemisphere due to the following factors:

• M 101 is located just off the handle of the Big Dipper in the constellation Ursa Major. 
• M 101 is a popular target for amateur astronomers, especially in the northern Hemisphere's spring, known to amateur astronomers as galaxy season. 
• M101 is high in the sky, making it favorable for observation. 
• Astronomically speaking, 21 million light years is "close" and therefore SN 2023ixf appears bright.

This event is for those of us located in the northern hemisphere, as M 101 is near the North Celestial Pole. Unfortunate news for our friends in the southern hemisphere. I don't feel too bad for them, as they have had their fair share of amazing events and amazing objects not accessible to those of us in the north.

A finder chart for finding M 101.

My Observations:

Night 1 - Sunday May 21, 2023:

My first shot at SN 2023ixf was Sunday May 21st. The forecast was calling for clear skies. Unfortunately, the forecast was also calling for dense smoke because of the wildfires in Alberta, Canada. I set up well before dark and hoped for the best. As it got dark, the stars were slow to appear. I could make out the crescent Moon near the horizon in the west and Venus was visible a little higher in the western sky. About 10 minutes before 10 pm, I could see Arcturus followed by a few stars in the Big Dipper. The smoke was definitely impacting the visibility of the stars. I decided to connect to my guide camera and see polar alignment was possible, and it was successful. Followed this up by slewing the telescope to the south, to an object close to where the Meridian and Celestial Equator (Dec = 0) for PHD2 guiding calibration. Again, this was successful. With both tasks successful completed, it was time to go for the supernova. I recently imaged M 101 at the end of April (click here). One of my sub exposures from that session was used to frame the target, this would capture the object in the same orientation, facilitating before and after comparisons. After slewing to M 101, rotating the camera to match the previous image, and performing an autofocus run, NINA started capturing the first image. SN 2023ixf was clearly visible in the resulting image, even though the galaxy details were subdued by the smoke. NINA continued to capture exposures, and SharpCap live stacked them. I don't have the writing skills to properly convey how exciting this was. 

Prior to starting the image session, I connected to an impromptu Zoom meeting with members of our local astronomy club, the Buffalo Astronomical Association (BAA). I was joined by our Observatory Director and a member from a sister club in Rochester, NY (who also belongs to our club). This person maintains a very useful website on supernovae (click here). It's a fantastic resource and I've used it for years before meeting him in person at our last club picnic. 

A total of 26 Images were captured from 10:07 PM to 11:17 PM, when the conditions degraded, and it no longer made sense to continue. Exposures were 120 sec each at a Gain of 100 with an Offset of 50. The images were captured on my Home Setup:

• Telescope: Explore Scientific Essential Series ED80 Air Spaced Triplet
• Mount: Sky-Watcher EQ6-R Pro
• Camera: ZWO ASI2600MC Pro
• Filter: None
• Accessories: Pegasus Astro Pocket Power Box Advanced, ZWO EAF, ZWO ASI224MC, Explore Scientific Field Flattener, & Orion 50 mm Mini Guide Scope 
• Software: NINA, PHD2, SharpCap, & PixInsight

Single 120 sec exposure. A screenshot from the capture software NINA. Only a screen (display) stretch applied, no other processing. Look how bright the supernova is compared to the galaxy. 

The live stacked image from SharpCap. This is a a total of 26 exposures at 120 sec each for a total exposure of 52 minutes. The image was saved with the display stretch and the plug-in NoiseXTerminaror was applied in PixInsight to reduce the noise in the image.

The final processed image. A total of 22 exposures were used (the last 4 images captured were too severely degraded to use). The image was processed in PixInsight. 

Night 2 - Monday May 22, 2023: 

The forecast was calling for clear skies and dense smoke. I headed out to the Buffalo Astronomical Association's observatory (Beaver Meadow Observatory) for our weekly imaging group session. The group is called the Tuesday Night Imagers, but "Tuesday" can be pretty much any day of the week. This week it was Monday. I set up my ZWO ASI2600MC Pro on the club's Tele Vue NP-101is and another member setup his ZWO ASI1600MM Pro on the club's Celestron 14" Edge HD Telescope. Both scopes sit atop an Astro Physics AP1200 mount in our main observatory. The club's Observatory Director is the leader of the Tuesday Night group. He was traveling, so another member and I were running the session in his place. We made a couple of critical errors which will make getting anything off of the 14'" scope a challenge. The first issue is the OAG prism wasn't properly lined up with the imaging camera's sensor. This resulted in a prominent shadow in the corner of the exposures. Compounding this error, we took flats at Bin 1, which does not match our light frames taken at Bin 2. There may be a way to salvage the data, but that will have to wait for another day. 

In addition to running the Tuesday Night session in place of the group's leader, we had an unusually large turnout due to the excitement of the supernova. Unfortunately, the smoke was very dense. most left around 10:30 PM. The supernova was visible in exposures but hardly any detail of the galaxy. Two of us stayed behind to troubleshoot the shadow issue on the 14". We continued to take exposures. We experienced a brief window where the smoke was not so dense. We captured images in both scopes for about a half an hour. After which we shut everything down and went home. 

BAA members setting up outside the observatory to observe/image the Supernova.

The Moon and Venus

Another view of the Moon and Venus

The Moon and Venus over our (the BAA) newly acquired Sky shed Pod.

A photo of the screen showing a single 120 sec exposure of from the NP-101is when the smoke briefly cleared.  BAA Tuesday Night Imagers.

A photo of the screen showing a 120 sec exposure from the 14" Edge HD.

BAA Tuesday Night Imagers.

Processed image captured on the NP-101is. Image was processed in PixInsight. BAA Tuesday Night Imagers.

Night 3 - Wednesday May 24, 2023

Conditions were much better on Wednesday May 24th. My scope (Home Setup) was still setup from Monday Night. I imaged from dark until about 1:30 AM, when I lost this object to a tree. Unfortunately, after processing the image, I accidentally deleted the raw data while moving files to a backup hard drive, as the hard drive on my imaging computer was getting full. Needless to say, I'm not pleased with myself about this mistake! This image was made from a total of 85 exposures at 120 seconds / Gain 100 / Offset 50 each for a total exposure of 2.8 hours. Processing was done in PixInsight. 

Night 4 - Thursday May 25, 2023

Conditions were very good again on Thursday May 25, 2023. Another image from my home setup. I imaged from 9:52 PM until 1:27 AM. Conditions were good enough that I continued to image another target (while I slept) after losing M 101. That will be covered in a future post. As the Moon was getting brighter and setting later, I decided to back off on my exposure time from 120 seconds to 60 sec. This image was made from a total of 145 exposures at 60 sec / Gain 100 / Offset 50 for a total exposure of 2.4 hours.

Putting all together in a Movie/Animation

Starting with my image of M101 from 4/26 (before the Supernova), I Star Aligned the processed images from each night using PixInsight. Then cropped them with Dynamic Crop in PixInsight. Photoshop was used to add the markers, the text, and to create the animation. Each frame has a 2 second duration. I converted the animation from a GIF to a MP4 movie file. Hope you like the result.

So, What's Next?

SN 2023ixf will be visible for a few more weeks. It will slowly dim.  Will probably try and capture some more data if time and weather allow. Our Observatory Director and the person from the Rochester club that maintains the supernova website both provided me with information on how to determine the magnitude of the Supernova from my images. I intend to sit down and learn how to do this. When, not sure. When I do figure it out, I'll make another post or amend this one. 

Clear Skies!

Ernie