Wednesday, October 9, 2024
FIRST LIGHT FOR MY NEW IMAGING SETUP
After a couple of years I'm able to publish a bran new photo!
This is a first light to my new imaging setup, it took couple of years to get it up and running.
I selected a relatively bright target since I wanted to test the system as soon as possible. The Pelican Nebula in constellation Cygnus, the Swan, is my first target.
The new system has a focal length of 2730mm with a massive 0.7 focal reducer for the Celestron EDGE 14" telescope. The new camera has 12 micron pixel size and it gives me an image scale of 0.91 arc seconds/pixel. (That's perfect for my seeing conditions.) The field of view spans 46.1 x 46.1 arcminutes of sky. (For a scale, Full Moon covers 30x30 arcminutes of sky)
The native resolution of the Apogee Alta U9000M camera is 3056x3056 pixels. I'm using a stacking method that doubles the measures by using the "Drizzle" while imaging. The final image is then 6112x6112 pixels.
Only five hours of light from an ionized hydrogen (H-alpha) is used for this photo. Other two color channels, O-III and S-II, are borrowed from my older long focal length photo of this target taken with Celestron EDGE 11" telescope.
Pelican Nebula
Click the photo to see a 2000x2000 pixel version
Click the image to see a full size version
This photo is in mapped colors from light from an ionized elements, hydrogen = green, sulfur=red and oxygen=blue. (H-alpha, S-II and O-III)
A Full Size H-alpha Frame
Click the image to see a full size version, 3056x3056 pixels
Click the image to see a full size version, 3056x3056 pixels
This is a stretched stack of fifteen 20min. calibrated H-alpha frames. Collimation wasn't perfect at the time so some oval stars can be seen in lower right corner. Now the collimation is under one arcseconds and the whole frame has pinpoint stars from corner to corner. (It's a large CCD, diagonal is 52mm) Optical analysis at end of this blog post,
Herbig-Haro Objects
Herbig–Haro (HH) objects are bright patches of nebulosity associated with newborn stars. They are formed when narrow jets of partially ionized gas ejected by stars collide with nearby clouds of gas and dust at several hundred kilometers per second. Herbig–Haro objects are commonly found in star-forming regions. (Source, Wikipedia)
I have labeled Herbig-Haro Objects in this closeup from my photo.
Technical details
Processing workflow
Image acquisition, MaxiDL v5.07.
Stacked and calibrated in CCDStack2.
Deconvolution with a CCDStack2 Positive Constraint, 27 iterations, added at 50% weight
Color combine in PS CS3
Levels and curves in PS CS3.
Imaging optics
Celestron EDGE 14" with 0.7 Focal reducer
Mount
MesuMount Mark II
Cameras and filters
Imaging camera Apogee Alta U9000M and Apogee seven slot filter wheel
Guider camera, Lodestar x 2 and SXV-AO Active Optics @ 6hz
Astrodon filters,
5nm H-alpha 3nm S-II and 3nm O-III
Total exposure time
H-alpha, 15 x 1200 s, binned 1x1 = 5 h (Data from new setup)
O-III, 3x 1200 s, binned 2x2 = 1h (Older data with 11" Celestron EDGE)
S-II, 3 x 1200 s. binned 2x2 = 1h (Older data with 11" Celestron EDGE
Saturday, September 28, 2024
NEW SETUP FOR MY ASTRONOMICAL NATURE IMAGING WORK
I haven't publish much new images in past two three years since I have had some health problems. Now I'm good as new and can start working again. Past two years I have been slowly building a new imaging platform. I have done some shorter focal length work past six years, now it's time to go closer again.
OPTICS
System is build around Celestron EDGE 14" telescope, I selected this scope due to its light gathering capacity, 356mm diameter and 3910mm native focal length (This very large and heavy 0.7 Reducer is especially made for the EDGE 14") One main difference to normal Celestron EDGE telescope is that I have added a secondary mirror focuser (by Optec) to get rid of a mirror flop. It can be a problem, especially with a heavy mirror. Bottom line, this scope has an excellent optical quality. There is some optical analysis and a single full scale 20min frame at end of this post.
In future I can add a "HyperStar system" to replace secondary mirror and use this telescope as a fast f2 astrograph.
Secondary mirror focuser, Note a curved vane for the flat power/data cable, no diffraction spikes!
The focuser is made all aluminium, it's really robust and easy to collimate.
The focuser is made all aluminium, it's really robust and easy to collimate.
MOUNT
I ended up to a MESU Mount MARK II since it has 100kg capacity at imaging work with a periodic error less than 4 arcseconds peak-to-peak, impressive numbers indeed. It also has zero lash back due to its friction drive system. One of the nice features is the 80mm diameter channel for all of the cords, trough the Ra and Dec axes, no more dragging cords!
The pillar I ordered with the mount is bended knee pillar type, no meridian flip is needed and telescope can track whole sky without stopping. The pillar came in easy to handle parts and assembly was very straight forward, the assembled pillar is very rigid under the weight of heavy telescope, counter weights and accessories.
Mesu mount is absolute beautiful engineering work. Support from manufacture is also very good. I had some minor problems with settings at first but they get solved in no time after we went it trough with remote connection, while on site. Bottom line, money wise this mount is a real bargain, if compared its features to any other brand or model of mount.
Bended Knee Pillar angle at my location 65 degree North.
Counter weights are stainless steal weight lifting weights. (~35kg)
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CAMERA
The Main camera is a "new" Apogee Alta U9000M with Apogee Filter wheel. It's a second hand camera originally used for the microscopic work and it looks like a bran new, There wasn't any mechanical shutter but I moved a shutter from my old Apogee Alta U16 to this new camera. (My old camera died to an old age)
The camera has 12 micron pixels, it's a perfect match to this optical configuration giving an image scale of 0.91 arcseconds per pixel. The full image spans 46.1 x 46.1 arcminutes of sky. (One degree is 60 arcminutes and Full Moon spans around 30 arcminutes of sky)
INSTRUMENT ROTATOR
At first time I have added an instrument rotator to the imaging path. I haven't use any rotator earlier since there is always some flexure.
The Wanderer Astro Rotator Pro has absolute zero flexure by the manufacture. I was very skeptical to this since if it moves, it will flex. It turned out, that there is a patented system based on neodymium magnets around the light path holding everything tightly together when rotator moves.
After measuring carefully everything with the CCD-inspector software from test exposures under the starfield I can say, it really has no flexures at all. It's only 18 mm thick and fit to my limited back focus nicely. The rotator can handle flawlessly all the heavy load I have placed behind it.
ACTIVE OPTIC UNIT
Maybe an overkill but I have added an active optics unit to the light path. It's SXV-AO from Starlight Xpress UK.
I have had really good experiences doing long focal length imaging with AO unit during the years. It doesn't correct the actual seeing so much but it corrects every small or big error from heat bubbles and vibrations from heavy traffic, wind, etc. and it does that really really fast.
It's as easy to use as any OAG, especially after I had an instrument rotator. With 14" scope, I can guide around 10 HZ by using mag 11 guide star. The MESU Mount is really good but there is lots of mass to move when guiding corrections are made. With AO there is just a small refracting glass element to move instead of telescope and heavy accessories.
DATA & POWER BOX
An other new accessory is power and data box from Wanderer Astro. It makes the system less chaotic with all the data and power cords. Also controlling power and data connections can be done remotely in one software. It can handle nearly 20 amp at peak power.
DEW BUSTER
There is also my old Dew Buster installed to the telescope. it can keep the temperature just little over the dew point, this prevent the heat current. Raising warm air inside the tube will ruin the image, if heater is even slightly too warm.
FAN
I added a 70 mm computer fan to the telescopes air went to reduce the cool down time. There is an air filter in the went to prevent the dust getting inside the OTA. I can control the fan speed by the Power Box software.
QHY POLEMASTER
This is a new addition too, I was amazed how easy it was to use. Polar align took maybe 15 min and it's easy to redo at any time needed. here is a REVIEW about this little helper,
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Telescope elements labeled
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QHY Polemaster, lens cover removed and ready for the action.
LENS COVER
As a last item here is a lens cover for Celestron EDGE 14" telescope. It's a simple and a must accessory to prevent dust in the collector lens. How ever, in my case there is a secondary mirror focuser sticking out and it prevents to use the standard Celestron aluminium cover over the telescope.
I solved the problem by cutting a circular hole in the lens cover. After that, I bought a steel bowl from local market ( it was just 5 € or about 5 $) I sprayed it matt black and glued it to the cover with an elastic, rubber like, superglue.
A steel bowl glued over the hole in the lens cover.
AN UPDATE, 09.10.2024,
THE FIRST LIGHT IMAGE
THE FIRST LIGHT IMAGE
Click for a full size image, ~2000x2000 pixels
https://astroanarchy.blogspot.com/2024/10/first-light-for-my-new-imaging-setup.html
OPTICAL ANALYSIS FROM THE CCDINSPECTOR APP
The optical collimation is as good as I get it in my seeing conditions and the optical tube hold it perfectly since the main mirror is always locked down and focusing is done with the Optec Secondary Mirror Focuser only.
This is a 3D-plot of field curvature from the CCDInspector app of Celestron Edge 14" with 0.7 Focal Reducer and Apogee Alta U9000M with 12 micron pixels. This configuration produce a very flat field and stars are sharp from edge to edge in the whole field. This is impressive especially since the CCD in Alta U9000M is so large, about 37x37mm.
A single full scale 20 min O-III exposure used for the optical analysis
Tuesday, August 8, 2023
Grand Mosaic of the Milky Way is now large than ever
Last Spring I published a large mosaic photo of the Milky Way and it went viral!
A blog post about it can be seen here: https://astroanarchy.blogspot.com/2021/03/gigapixel-mosaic-of-milky-way-1250.html
I have now even a large version of it, the mosaic spans 145 degrees of sky from Orion to Cygnus, the previous version showed 120 degrees of sky.
The new panorama image was published today in Finnish Tähdet ja Avaruus Magazine
The new panorama image was published today in Finnish Tähdet ja Avaruus Magazine
at first time in the World.
.BUY A POSTER
The Grand Mosaic of the Milky Way Galaxy II
This is the only photo in the World showing the Northern Milky Way so deep and detailed, now it's large than ever!
Click for a large image, 7000 x 1150 pixels
Over a decade, 1500 exposure hours and 301 individual frames visible in one image
NOTE, image of the Full Moon as a scale in lover left corner.
NOTE, image of the Full Moon as a scale in lover left corner.
NEW! ZOOMABLE IMAGE
23.000 x 3500 pixels
You can now pan and zoom around the large image. Photo size is reduced to 40.000 x 6000 pixels from original 120.000 x 18.000 pixels to save some bandwidth.
NOTE, all material in this blog is under copyright, any kind of usage without authors permission is forbidden.
NOTE, all material in this blog is under copyright, any kind of usage without authors permission is forbidden.
IMAGE SPECS
- Panorama spans 145 x 22 degrees of sky (Full Moon covers 0,5 degrees of sky)
- Resolution 120.000 x 18.000 pixels
- Photos has 2.2 gigapixels in it, the spatial resolution is equal to 8.8 gigapixel image from color camera since all the channels are in native resolution.
- There are least nine confirmed supernova remnants in this panorama
- About 25 million stars are visible in the photo
- Distance to the nebulae in the image between 350 to 20.000 light years
- Exposure time over 1500 hours between 2009 - 2021
- 301 individual images are stitched together seamlessly
- It took about 12 years to finalize this photo
- Narrowband image from light of ionized elements, hydrogen = green, sulfur = red and oxygen = blue
- Processing time for the whole panorama, way too large part of my life
ORIENTATION
Click for a large image
CLOSEUP SERIES
Click for the large images, it's worth it!
A zoom in series from upper left of the large panorama image above to gives an idea about the overall resolution of the large mosaic image.
All the dots are stars, not the noise!
Closeup of the supernova remnant IC 443
DETAILS
Click for a large image, 5000 x 1500 pixels
There are several very dim and practically unimaged supernova remnants in this panorama.
NOTE, all material in this blog is under copyright, any kind of usage without authors permission is forbidden.
NOTE, all material in this blog is under copyright, any kind of usage without authors permission is forbidden.
NEW! ZOOMABLE IMAGE
11500 x 3400 pixels
11500 x 3400 pixels
The reason I keep doing my slow work is an endless
curiosity, I love to show how wonderful our world really is. That's how I feel at front of
everything I'm able to see through my photography.
Photographed area of sky is showing a large part of Northern Milky Way in high resolution. Beside the size, it's very deep, meaning that it shows extremely dim and unimaged nebulae across the galaxy plane. One of the reasons for this massive panorama project was a fact, that there was no such an image anywhere in the world. I had personal need for the photo like this since I wanted to use it as a map to the new adventures.
Revealing the hidden beauty of our universe is my passion. I stand in rapt adoration before all that I see. When art meets science, the results can be quite mind-blowing.
HOW?
Step 1,
PLANNING
Astronomical
photography is a very time-consuming process. If I want to have a color image,
I have to shoot each target least three times through a different filter to
have all three-color channels needed for color image. Also, the exposure times
can be very long, in my case even hundreds of hours for some very dim
objects. An average exposure time is around 25 hours per image. Also everything has
to be carefully pre planned.
I made imaging plans over ten years ago, I
wrote first ideas about this imaging project to my little black Moleskin
notebook. I was aware at the time, that it will take a decade to be
finalized but it doesn't bother me since I love long projects, they are
giving a purpose and the goal to my work as an artist.
My little black notebook and first plans
for the project at 2008
A notebook page opening from Autumn 2008
I needed to develop many new working
methods to be able to control this massive project. I needed to get them ready
first since ones started, the project can't be changed anymore without
canceling it. Everything needs to be spot on, the planning of composition and
its relation to the Milky Way objects, many technical aspects, like how to
handle a data from different optics with a different spatial resolution etc. I
won't go very deep into technical details, since the complex technique needed
is just a tool to make my art.
I like to compare my long imaging projects to a relationship. This project was like that too but not just between two entities. This is like a relationship with the whole family, a large Klan. There might be a nasty drunk uncle or other difficult persons in a family but
you must be able to get along with them too. I felt like that, when I was stitching pieces
together and some of them didn't fit the way I wanted and I had to reshoot them. That easily took months, or years. but at the end, everything slides together smoothly without any visible seams.
I'm a perfectionist, when dealing with my photography. This feature is essential for the great results but it also can cause problems. This photo could be ready maybe five years earlier, if I could leave some extremely dim targets out or leave them less detailed but I simply couldn't do that. When the photo was ready, I didn't remember all of those sleepless cold nights, I remembered the joy I felt when the most difficult parts got ready.
you must be able to get along with them too. I felt like that, when I was stitching pieces
together and some of them didn't fit the way I wanted and I had to reshoot them. That easily took months, or years. but at the end, everything slides together smoothly without any visible seams.
I'm a perfectionist, when dealing with my photography. This feature is essential for the great results but it also can cause problems. This photo could be ready maybe five years earlier, if I could leave some extremely dim targets out or leave them less detailed but I simply couldn't do that. When the photo was ready, I didn't remember all of those sleepless cold nights, I remembered the joy I felt when the most difficult parts got ready.
Step 2,
COLLECTING THE MATERIAL
2009 - 2021
NOTE
Each photo in the posters is a slow and complex battle of its own
Click for a large image
Some of my individual photos shot between 2009 and 2021 are collected here. Most of them are now part of the Large Mosaic Image of the Milky Way galaxy.
NOTE, all material in this blog is under copyright, any kind of usage without authors permission is forbidden.
NOTE, all material in this blog is under copyright, any kind of usage without authors permission is forbidden.
Step 3,
2019 -2021, SOLVING THE BIG PUZZLE
Finally at 2019, after so many years, I had enough material to start
working with the final mosaic image. The work took about two years due to
complex mosaic structure and massive amount of image material. I also
needed to shoot lots of missing material for the mosaic at the same time.
I used the Cartes du Ciel, a star map software, for planning and a
preliminary fit the individual frames.
EVOLUTION OF THE LARGE MOSAIC
BETWEEN 2009-2021
Click for a large image
Step 4,
ALL THE PIECES OF A
COSMIC PUZZLE CONNECTED
Click for a large image
The final photo is over 120 000 pixels wide and it has 301 individual mosaic panel. Most of the objects are originally shot as a self-standing artworks, due to that, they
are in various positions and angles to each other. This is the reason, why the
final mosaic structure looks so complicated, as can be seen in this image.
AND FINALLY
At October 2021, after 12 years, 1500 hours of exposures and countless hours of work
The Grand Mosaic of the Milky Way Galaxy II
Click for a full size image, 7000 x 4300 pixels
NOTE, all material in this blog is under copyright, any kind of usage without authors permission is forbidden.
NOTE, all material in this blog is under copyright, any kind of usage without authors permission is forbidden.
Getting to a last piece of the puzzle is always a thrilling process. Many
of us know, how frustrating it can be to notice, that one piece is missing. That's
happened to me too. I was sure that I shot the piece about three years ago
but couldn't find it anywhere from my hard drives. As a result, I had to wait
several extremely long weeks to be able to reshoot the missing piece to get
this massive puzzle finalized.
The Mosaic Work, technical info
I have used several optical configurations for this mosaic image during the years. Up to 2014 I was using an old Meade LX200 GPS 12" scope, QHY9 astrocam, Canon E200mmf1.8 camera optics and baader narrowband filter set.
After 2014 I have had 10-micron 1000 equatorial mount, Apogee Alta U16 astro camera, Tokina AT-x 200mm f2.8 camera lens and the Astrodon 50mm square narrowband filter set.
I have shot many details with a longer focal length, before 2014 by using Meade 12" scope with reducer and after 2014 Celestron EDGE 11" and reducer. Quider camera has been Lodestar and Lodestar II.
I took my current toolset as a base tool since it has a relatively high resolution combined to a very large field of view. Also it collects photons very quickly since it's undersampled and I can have very dim background nebulosity visible in very short time (many times 30 min frame is enough)
I do all my mosaic work under the PhotoShop, Matching the separate panels by using stars as an indicator is kind of straight forward work. My processing has become so constant, that very little tweaking was needed between separate frames, just some minor levels, curves and color balance.
I have used lots of longer focal length sub-frames in my mosaic to boost details. (See the mosaic map at top of the page) To match them with shorter focal length shots I developed a new method.
Firstly I upscale the short focal length frames about 25% to have more room for high resolution images.Then I match the high res photo to a mosaic by using the stars as an indicator. After that I remove all the tiny stars from the high res image. Next I separate stars from low res photo and merge the starless high res data to a starless low res frame. And finally I place the removed low res stars back at top of everything with zero data lost. Usually there are some optical distortions and it's seen especially in a star field. Now all my stars are coming from a same optical setup and I don't have any problems with distortions. (I'm using the same star removal technique as in my Tone Mapping Workflow)
Wednesday, December 21, 2022
Milky Way, 12 years, 1250 hours of exposures and 125 x 22 degrees of sky
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https://astroanarchy.zenfolio.com/
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It took nearly twelve years to collect enough data for this high resolution gigapixel class mosaic image of the Milky Way. Total exposure time used is around 1250 hours between 2009 and 2021.
" I can hear music in this composition, from the high sounds of sparcs and bubbles at left all the way to a deep and massive sounds at right."
From Taurus to Cygnus
Click for a large image, it's really worth it! (7000 x 1300 pixels)
Image in mapped colors from the light emitted by an ionized elements, hydrogen = green, sulfur = red and oxygen = blue. NOTE, the apparent size of the Moon in a lower left corner. NOTE 2, there are two 1:1 scale enlargements from the full size original at both ends of the image
NEW, A HD-video from Germany shows my photo in full glory
https://www.youtube.com/watch?v=D-Z60eZ4yqM
(Video in Germany but images are the international language)
Close ups form the parts of the Grande Mosaic
NEW, A HD-video from Germany shows my photo in full glory
https://www.youtube.com/watch?v=D-Z60eZ4yqM
(Video in Germany but images are the international language)
Close ups form the parts of the Grande Mosaic
Cygnus side of the mosaic, https://astroanarchy.blogspot.com/2020/12/cygnus-project-grande-finale-for-now.html
Cassiopeia side of the mosaic, https://astroanarchy.blogspot.com/2021/01/mosaic-image-gets-large-400-hours-and.html
Taurus side of the mosaic, https://astroanarchy.blogspot.com/2021/02/a-new-mosaic-image-from-taurus-to.html
A closeup from large panorama to show the overall resolution
Click for a large image
The California Nebula, NGC 1499, can be seen at bottom left of the large mosaic image.
There are about 20 million individual stars visible in the whole mosaic image.
There are about 20 million individual stars visible in the whole mosaic image.
Orientation and details
Click for a large image
Click for a large image
Imaging info
Image spans 125 x 22 degrees of the Milky About 20 million individual stars are visible in my photo!
Image spans 125 x 22 degrees of the Milky About 20 million individual stars are visible in my photo!
It took almost twelve years to finalize this mosaic image. The reason for a long time period is naturally the size of the mosaic and the fact, that image is very deep. Another reason is that I have soht most of the mosaic frames as an individual compositions and publish them as independent artworks. That leads to a kind of complex image set witch is partly overlapping with a lots of unimaged areas between and around frames. I have shot the missing data now and then during the years and last year I was able to publish many sub mosaic images as I got them ready first.
My processing workflow is very constant so very little tweaking was needed between the mosaic frames. Total exposure time is over 1250 hours. Some of the frames has more exposure time, than others. There are some extremely dim objects clearly visible in this composition, like a extremely dim supernova remnant W63, the Cygnus Shell. It lays about six degrees up from North America nebula and it can be seen as a pale blue ring. I spent about 100 hours for this SNR alone. An other large and faint supernova remnant in Cygnus can be seen at near right edge of the image. G65.5+5.7 is as large as more famous Veil nebula. There are over 60 exposure hours for this SNR alone. (Veil SNR is just outside of the mosaic area for compositional reasons but can be seen in "Detail" image above.)
My processing workflow is very constant so very little tweaking was needed between the mosaic frames. Total exposure time is over 1250 hours. Some of the frames has more exposure time, than others. There are some extremely dim objects clearly visible in this composition, like a extremely dim supernova remnant W63, the Cygnus Shell. It lays about six degrees up from North America nebula and it can be seen as a pale blue ring. I spent about 100 hours for this SNR alone. An other large and faint supernova remnant in Cygnus can be seen at near right edge of the image. G65.5+5.7 is as large as more famous Veil nebula. There are over 60 exposure hours for this SNR alone. (Veil SNR is just outside of the mosaic area for compositional reasons but can be seen in "Detail" image above.)
The Mosaic Work, technical info
I took my current toolset as a base tool since it has a relatively high resolution combined to a very large field of view. Also it collects photons very quickly since it's undersampled and I can have very dim background nebulosity visible in very short time (many times 30 min frame is enough)
I do all my mosaic work under the PhotoShop, Matching the separate panels by using stars as an indicator is kind of straight forward work. My processing has become so constant, that very little tweaking is needed between separate frames, just some minor levels, curves and color balance.
I have used lots of longer focal length sub-frames in my mosaic to boost details. (See the mosaic map at top of the page) To match them with shorter focal length shots I developed a new method.
Firstly I upscale the short focal length frames about 25% to have more room for high resolution images.Then I match the high res photo to a mosaic by using the stars as an indicator. After that I remove all the tiny stars from the high res image. Next I separate stars from low res photo and merge the starless high res data to a starless low res frame. And finally I place the removed low res stars back at top of everything with zero data lost. Usually there are some optical distortions and it's seen especially in a star field. Now all my stars are coming from a same optical setup and I don't have any problems with distortions. (I'm using the same star removal technique as in my Tone Mapping Workflow)
Closeups from large panorama to show the overall resolution
Click for a large image
IC 405 6 410 area
IC 1396
Click for a large image
Image in mapped colors from the light emitted by an ionized elements, hydrogen = green, sulfur = red and oxygen = blue.
A 1:3 resolution close up from the photo above
Click for a large image,
Click for a large image,
A closeup from the main image shows the Sharpless 124 at up and the Cocoon nebula with a dark gas stream at bottom.
Sharpless 205, NGC 1491 and Lynds Bright Nebula 696
IC 405 6 410 area
From Bubble to Cave Nebula
Image info, https://astroanarchy.blogspot.com/2020/03/from-bubble-to-cave-nebula-area.html
Not an igloo, this is reality of astro photographing in Finland
The tulip nebula area
The Tulip Nebula, Sh2-101, can be seen at center right, there is also a black hole Cygnus X-1
The blog post with technical details can be seen here, https://astroanarchy.blogspot.com/2020/10/the-tulip-nebula-in-cygnus-sh2-101.html
The blog post with technical details can be seen here, https://astroanarchy.blogspot.com/2020/10/the-tulip-nebula-in-cygnus-sh2-101.html
The supernova remnant G65.3+5.7
More info about this image here, https://astroanarchy.blogspot.com/2020/11/g65357-large-supernova-remnant-in_22.html
My Observatory,
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