The Bubble Nebula

Today I present the Bubble Nebula, NGC 7635, taken over six nights, from July 17 to August 22, with my EdgeHD11 scope and ASI2600mm camera. The best images (those that are very noise free) require a long amount of integration time. I rarely spend multiple nights to get one image with the rarity of clear nights here in Maryland, but I wanted an image that would really stand out.

The Bubble Nebula - July/August 2023
EdgeHD11 OTA with ASI2600mm Camera
29.5 hours integration time (NB and RGB Filters)

The Bubble Nebula is 7 light-years across and resides 7,100 light-years from Earth in the constellation Cassiopeia. The "bubble" is created by the stellar wind from a massively hot young central star. The nebula lies near a giant molecular cloud in space (which can be seen across the image as the yellowish-red cloud).  The bubble nebula itself is being excited by that hot central star (just to the right of the center of the bubble), causing it to glow. It was discovered in November 1787 by William Herschel.

Here is the Hubble telescope image of the same object for comparison.

Bubble from Hubble

Some Globular Clusters and a New Project

In early May there was a decent break in the lousy weather we've been having, and even though I'm still having to deal with the Canadian forest fire smoke, I decided to go for some easy captures (well, relatively easy) while I can.

First up is a famous star cluster, Messier 13 (or M13). This cluster of stars is sometimes called the Great Globular Cluster in Hercules or the Hercules Globular Cluster.  It contains about 300,000 stars and is estimated to be just under 12 billion years old. It is so dense that near the core there are as many as 100 stars per cubic LY. M13 is about 22,200 LY from earth.

M13 - May 9, 2023
EdgeHD11/ASI533MC - 77×120″ subs

Second is another globular cluster, M3. This cluster is one of the largest and brightest, and is made up of around 500,000 stars. It is estimated to be 11.4 billion years old. It is centered at 32,600 light-years away from Earth. (Wiki)

M3 - May 10, 2023
EdgeHD11/ASI533MC - 110×120″

I am now planning on a new project which may take a number of weeks to complete. Back in October of 2019 I captured the iconic Bubble Nebula with my GT102 APO refractor and ASI1600mm camera. I was still learning a lot back then (both in capture techniques and processing tools), and although the result was quite good, it lacked the 'wow' factor that I've seen in other images of this deep space object. 

With my new equipment (ASI2600mm camera and new Optolong 2" NarrowBand filters) ready I decided to redo the capture of the Bubble Nebula and try to get a better image. This is going to take a bit of effort since I will need about 60 subs (600 sec exposure each) of all three filters. That means I need about 35 hours of capture time (accounting for the exposures and periodic re-focusing time) to get the data I need. I will probably wait to early autumn to take advantage of the clearer skies and the longer periods of darkness. As a test I captured 28 subs (600 sec each) in Ha on July 17 to see how the camera performed. Can't wait to get the whole set of data later this year.

Test capture of C11 (Bubble Nebula)
EdgeHD11/ASI2600mm  28x600sec Ha

M51 - the Whirlpool Galaxy

Got a couple of clear nights with relatively little smoke so I decided to image the famous Whirlpool galaxy. I haven't taken a new image of M51 since back in 2014, when I just got started in astrophotography with my new EdgeHD11. I used a Canon 50D for that one.  So I figured it was about time I captured it with my upgraded equipment and new processing tools and skills.

As usual, sky conditions this year have been abysmal, and even when the sky was clear, the smoke from Canada usually played games with my imaging. But I did manage to get some decent skies on June 14 and 18, so went for it.  Turns out that the blue subs had some issues with registration (seems that happens a lot with my objects/subs - gotta check into that). But I decided to process with just the 19 blue subs since the weather isn't going to cooperate any time soon.

Whirlpool Galaxy (M51)
June 14 and 18, 2023 - EdgeHD11 and ASI2600mm 
LRGB - Total Integration time: 6h48m

The Whirlpool Galaxy, also known as Messier 51a (M51a) or NGC 5194, is an interacting grand-design spiral galaxy with a Seyfert 2 active galactic nucleus. It lies in the constellation Canes Venatici, and was the first galaxy to be classified as a spiral galaxy. It is between 23 and 31 million light-years away and 76,900 ly in diameter.

The galaxy and its companion, NGC 5195 (reddish galaxy to the left), are easily observed by amateur astronomers, and the two galaxies may be seen with binoculars. The Whirlpool Galaxy has been extensively observed by professional astronomers, and its pair with NGC 5195 who study it to understand galaxy structure (particularly structure associated with the spiral arms) and galaxy interactions. Its pair with NGC 5194 is among the most famous and relatively close interacting systems, and thus is a favorite subject of galaxy interaction models. (Wiki)

The Cat's Eye Nebula

Yesterday I promised that I would upload my latest image, the Cat's Eye nebula, and so here it is (with the off-color NB stars - I'll reprocess with RGB stars later when I acquire them).

NGC 6543 - the Cat's Eye Planetary Nebula
EdgeHD11/ASI2600mm - 42x600sec Ha; 43x600sec O3
14 hours integration time May 31, June 2 and June 5, 2023 

This is the famous Cat's Eye nebula, a remarkable planetary nebula (PN) located in the constellation of Draco the dragon. It was discovered by William Herschel on February 15, 1786. It resides at an  estimated distance of 3,262 light years from earth. The inner core is about 16 arc sec in diameter, which at it's current distance would make it about 0.25LY wide. Images from the Hubble telescope made this object a subject of popular review when they showed the central core of the nebula in exquisite detail, revealing knots, jets, bubbles and complex arcs, all being illuminated by the central hot planetary nebula nucleus. My image shows the surrounding outer halo (about 4.7LY in diameter) in the HOO NB color palette. Both the central WR:+O7 spectral class PNN star and the concentric rings surrounding the inner core can be plainly seen. Based on both the estimated distance and the expansion rate the age of this PN is about 800-1200 years old.

The image was composed of 42 Ha subs and 43 O3 subs, each 600 seconds of exposure. Since the nucleus of the nebula is so very bright (shining at magnitude 8) the 600 seconds really washed out the core and so I had to carefully process the image with a High Definition layer routine to bring out some of the internal detail and reduce the overall intensity.  There is evidence of some processing artifacts present, but adding more data later will probably resolve that issue.  I had also planned to capture RGB stars to replace the NB stars, but between the full moon and the smoke drifting into Maryland from the Canadian fires I had to forgo those and settle on the NB stars. I hope to replace them with RGB stars when I capture more data of this wonderful object.

Smoke in Maryland - And a Feature Article on Your's Truly

Here it is - Monday evening; clear sky, cool temps, low humidity. What more can you ask for? Should be a great night to capture the RGB stars I need for my latest project. But, where are the stars? And what's with Venus, so pink and dim, when it should be brilliant white. Why smoke, of course! Yep, the Canadian fires are filling our skies with a fairly thick haze of smoke. So no imaging tonight. I'll probably process the subs I got of the Cat's Eye nebula without the colored stars. Maybe I'll capture them later and add them in at a later date. I'll post the image later this week.

On another note ... back in March, Photonic Cleaning Technologies, a company that developed a polymer cleaning solution used by professional observatories and industrial optical organizations, contacted me after I had a conversation with one of the owner/engineers about using their First Contact Polymer to clean my telescope optics. We had a great talk about astronomy and astrophotography, and it was soon after that conversation that Debra Giesen emailed me about publishing an article about my hobby on their website. Of course I jumped on the opportunity and started writing the first draft. All I needed to do is agree to include a short  testimony on how I liked the Polymer cleaner. Not only would the article be posted on their website, but would be a feature article in the June edition of Amateur Astrophotography Magazine.

Well, things didn't go all that well. The owner/creator/manager of Amateur Astrophotography Magazine is temporarily suspending future publishing until early next year as he deals with some medical issues. He is confident that the magazine will be back in operation in early 2024 and I will be first on the publication list. But the article, "Astrophotography from Light Polluted Reisterstown" is posted on the Photonic Cleaning Technologies website. Check it out.

Supernova 2023ixf in M101

I'm sure many of you may already know of the supernova that occurred in the Pinwheel galaxy, M101. I wanted to capture it as soon as I could but, as usual, clouds prevented me from doing so until May 26, when it cleared sufficiently to get a decent image.

I had taken an image of M101 way back on Dec 28, 2013, when I was just starting out with astrophotography. I had recently acquired my large telescope (the EdgeHD11) and this was one of my first attempts at imaging a galaxy. I didn't even own a dedicated astro camera back then - the image was taken with my Canon 50D body. I'm not sure why I haven't taken a recent image of M101 as it is a wonderful galaxy, but that's another story.

Amateur astronomer Koichi Itagaki discovered it on May 19, 2023. The supernova should remain visible to amateur astronomers with backyard telescopes for a few months. The supernova – named 2023ixf – lies in the direction of the constellation Ursa Major, near the end of the handle of the Big Dipper.

So here is my image of M101 with the supernova marked (and the 2013 image for reference).

Supernova 2023ixf in M101
May 26, 2023 - EdgeHD11/ASI533mc
40x180sec with UV/IR block filter

M101 - Dec 28, 2013
EdgeHD11/Canon 50D
12x120sec ISO 3200

You can read more about this object at SkyAndTelescope.  Details of my image can be found at Astrobin.

Latest image from Mikey's Place - the Sombrero Galaxy

Since galaxy season is upon us I decided to give the ASI533mc a workout. For those of you who do not know what galaxy season is here is a short explanation.

There is a region in the sky where a significant number (the vast majority actually) of galaxies congregate. As the Earth swings around its orbit in the spring, it faces the plane of the our own Milky Way but at night it faces a part of the sky that reveals what some of us call the Realm of the Galaxies. During the months of April, May and June, several hundred of these galaxies become easy to image with telescopes of 10 inches aperture or more. And, with just a little extra effort, up to thousands can be imaged but will appear rather small as they are much farther distant.

Most of these galaxies are clustered around the constellation Leo the Lion and just beyond Leo's tail. This cluster, some 4,500 or more of them, is known as the Coma-Virgo Cluster and lies about 60 million light years away. This enormous distance is why these galaxies are so faint. Some of these galaxies are larger and brighter than our Milky Way galaxy but still hard to see. 

Sombrero Galaxy - May 11, 2023
EdgeHD11 Telescope / ASI533mc camera
58x120sec subs thru UV/IR cut filter

The photo displayed here is the Sombrero Galaxy (one of the Messier objects, M104, and also designated as NGC 4594). It lies 31.1 million light years from the Milky Way and is slightly larger in size at about 94,900 light years in diameter (the Milky Way is estimated to have a diameter of 87,400 light years). Because of it's large distance from us it appears in the sky to be only 9' x4' (the ' is a minute of arc which is 1/60 of a degree, making the size about 0.15 degree in the long dimension). It has a very bright nucleus, and a rather large central bulge (which is unusual for galaxies). In addition it sports a prominent dust lane in its outer disk, which is viewed almost edge-on. It is the dark dust lane and the bulge that give it the appearance of a sombrero hat (thus the name).

More details about my image of the Sombrero can be found on AstroBin.

Update on the Medusa Nebula

 A few days ago I posted my image of the Medusa nebula. I had mentioned that there were some problems with the level of Sii data and that the blue star subs were really bad.

It turns out there were other issues as well - having to do with the settings used to calibrate and stack the narrowband subs. I sent my raw data files to a fellow astrophotographer out on Astrobin, Uwe Deutermann, and he was able to process them with no such issues and create a much better final image. Here is that result as a collaboration effort of the two of us: my data, Uwe's processing.

Medusa Nebula -- Abell 21, Sh2-274

Later on another astrophotographer on Astrobin, George Yendrey, provided a very complete evaluation of my issue with the processing and uncovered an incorrect setting/parameter I was using in calibrating the subs. Once I set the parameter correctly I was able to reprocess my data and get similar results to what Uwe had provided. Such is the huge benefit of having an online collaboration site like Astrobin where fellow astrophotographers can ask questions, and exchange knowledge.

The complete dialog of the journey to get this image can be found on Astrobin.

The Medusa nebula

Got some clear nights as of late so I immediately got the scope out under the stars to do some imaging.

Seems like everyone as of late is posting the Medusa nebula on Astrobin.  Mine is no where as good as any of them, but it is the object I used to check on my recently returned EdgeHD11 from Celestron (had it in for cleaning and maintenance) and my new Optolong filters and 2" FW. 

The Medusa Nebula is a planetary nebula in the constellation of Gemini. It is also known as Abell 21 and Sharpless 2-274. It was originally discovered in 1955 by University of California, Los Angeles astronomer George O. Abell, who classified it as an old planetary nebula. It is 1,500 light years distant spanning about 4 light years across.

I had lots of problems getting this object imaged. One is the lack of sufficient data in S2. The other was the fact that the focus on the Blue filter was off and so I got some wonky stars. Oh well, enough of the sad commentary, here it is.

The Medusa nebula - SHO w/RGB stars
March 19, 21 and 26, 2023
EdgeHD-11; ASI2600mm  -  9 hours Integration Time

There was another issue I had but that is potentially going to be discussed in a later post. I didn't do any calibration on these subs - no darks, no flats. This was because of something that was occurring in the PixInsight WBPP script that essentially wrecked my Ha stack. The O3 and S2 data were fine. Not sure why this happened, but I am researching it.

More details on this imaging run can be found on my Astrobin site.

Relativity Space launches 3D-printed Terran 1 rocket

I've always wanted to try out the new 3D printers that are all the rage these days, but I would never have guessed that a Space company would, or could, print a working rocket. 

On Wednesday night a Seattle company, Relativity Space, launched the first 3D-printed rocket, named "Terran 1", on a test mission from Cape Canaveral.  The primary aim of the flight was to put a completely new launch vehicle through its paces, and place a small memento plaque into orbit.  

Methane-tinged blue flames - Relativity Space / Michael Baylor © Provided by Geekwire

The takeoff of the two-stage, 110-foot-tall Terran 1, was picture perfect, and unique in that the exhaust was bright blue owing from that fact that it used Methane as a propellent (another experimental design feature).

The rocket successfully reached Max-Q, a point where the stress on the rocket's superstructure is the greatest, thus demonstrating that 3D printed components hold up to the severe stresses of launch and boost against the force of Earth's gravity.

But an anomaly in the second stage engine prevented stage two's ignition and thus made orbital insertion impossible. Nonetheless, the rocket demonstrated a first for space vehicles and future attempts to reach orbit are just around the corner as the company plans additional flights and larger vehicles.

Full article (and video) at: GeekWire

Experimenting with DuoBand filters

I was experimenting with the ZWO DuoBand filter that came with my ASI533mc using M42 as the subject.  This photo is a combination of images: DuoBand (180sec) + RGB (120sec) + RGB (30sec) Stars.  I processed the DuoBand subs separate from the RGB, producing two master images; one DuoBand the other RGB.  I extracted the R, G, and B from the DuoBand before applying the NBRGBCombination process in PixInsight.  I then used Bill Blanshan's technique for adding in the RGB stars (using the 30sec master). 

The core is a bit blown out, but the overall result is not all that bad. I'll need to try some other objects using this imaging combination and processing technique.