SH2-171 – The Teddy Bear Nebula - 33.5 Hours of SHO
Date: November 15, 2025
Cosgrove’s Cosmos Catalog ➤#0154
Sh2-171, the Teddy Bear Nebula, captured through narrowband filters (SHO). This 33.5-hour exposure reveals intricate pillars and billowing clouds of ionized gas and dust carved by the young cluster Berkeley 59. (Click image for hi-res version via AstroBin.com.)
An immense H II region in Cepheus, its sculpted pillars and glowing gas revealing the restless birth of new stars.
🔭 Project Summary
Target: Sh2-171 – NGC 7822 / Cederblad 214 Star-Forming Complex
Capture Dates: October 16, 17, 26–28, 2025
Constellation: Cepheus • Distance: ≈ 3,000 light-years
Type: Emission Nebula / H II Region & Stellar Nursery
Imaging Period: October 16–28, 2025 • Total Integration: 33 h 30 m (SHO)
Filters: Ha (6 nm) · O III (6 nm) · S II (6 nm)
Telescope: Astro-Physics 130 mm f/8.35 Starfire APO (≈1085 mm)
Camera: ZWO ASI2600MM-Pro (−15 °C; Gain 100 NB)
Mount: Custom Steel Pier (new permanent pier)
Processing: PixInsight (SHO) & Photoshop
Location: Whispering Skies Observatory · Honeoye Falls, NY (USA)
Acquisition notes: Narrowband 300-s subs: 130×Ha, 136×O III, 136×S II at −15 °C, Gain 100.
The Astro-Physics 130mm Platform! (click on image to go to the blog entry for this scope_)
📸 Capture Details
Nights: October 16, 17, 26–28, 2025
| Channel / Filter | Frames × Exposure | Settings | Total |
|---|---|---|---|
| Hα — Astronomik 6 nm (36 mm unmounted) | 130 × 300 s | bin 1×1 • −15 °C • Gain 100 | 10 h 50 m |
| O III — Astronomik 6 nm (36 mm unmounted) | 136 × 300 s | bin 1×1 • −15 °C • Gain 100 | 11 h 20 m |
| S II — Astronomik 6 nm (36 mm unmounted) | 136 × 300 s | bin 1×1 • −15 °C • Gain 100 | 11 h 20 m |
| Total Integration (after culling): 33 h 30 m (SHO) | |||
Calibration Frames
- 25 × dark frames @ 300 s, bin 1×1, −15 °C, Gain 100
- 30 × dark-flats @ flat exposure times, bin 1×1, −15 °C, Gain 100
- Flats (one set): 15 each — Ha, O3, S2
Table of Contents Show (Click on lines to navigate)
🔭 About The Target
Sharpless 2-171: A Stellar Nursery in Cepheus
Sharpless 2-171 (Sh2-171) is an expansive emission nebula—an H II region of glowing ionized hydrogen—in the northern constellation of Cepheus.
This sprawling cloud of gas and dust spans over a degree of sky, roughly three to four times the apparent diameter of the full Moon. At its estimated distance of approximately 3,000 light-years from Earth, that angular size corresponds to a physical diameter on the order of 100–150 light-years. Sh2-171 is part of a larger star-forming complex cataloged as NGC 7822, which also contains the young star cluster Berkeley 59 embedded in the nebula. The nebula emits a dim, reddish glow from excited hydrogen gas; despite its large extent, its surface brightness is quite low. As a result, Sharpless 171 can be challenging to observe visually and is best captured in long-exposure photographs or with the aid of filters that highlight its faint nebulosity.
Discovery and Historical Observations
NGC 7822 (the nebular complex encompassing Sh2-171) was first recorded by English astronomer John Herschel on November 16, 1829. Peering through his 18-inch reflector telescope, Herschel described a very faint, round patch of light in Cepheus and suspected it was just the central part of a much larger nebula that eluded direct view.
His observation was later entered as NGC 7822 in the New General Catalogue compiled by John Dreyer.
Nearly a century later, in 1946, Swedish astronomer Sven Cederblad included this nebula in his study of diffuse galactic nebulae, listing it as Cederblad 214 (Ced 214).
The region received the designation Sharpless 171 in 1959, when Stewart Sharpless published his catalogue of H II regions based on Palomar Observatory sky survey photographs. Over the years, improved telescopes and imaging techniques have revealed the true vastness and intricate structure of Sh2-171, which Herschel could only glimpse in the 19th century.
Star Formation and Scientific Significance
Sh2-171 is essentially a cosmic stellar nursery – an active region of star formation shaped by its young massive stars.
At its heart lies the infant cluster Berkeley 59, only a few million years old, which contains dozens of hot, blue-white stars that have recently ignited.
Among them is an O-type star cataloged as BD+66 1673, a blazing giant with an estimated surface temperature of nearly 45,000 K and a luminosity approximately 100,000 times that of our Sun. The intense ultraviolet light and powerful stellar winds from this and other massive newborn stars are ionizing the surrounding gas, causing the nebula’s diffuse glow.
They are literally carving the landscape of the nebula. Dense columns and ridges of darker material—often compared to the “Pillars of Creation” in the Eagle Nebula—stand as dark, elephant-trunk-like pillars against the glowing background, shaped by erosion from starlight and winds. Deep studies in optical and infrared light have revealed a wealth of newborn stars forming within Sharpless 171’s clouds, including many that are still in their early pre–main–sequence phase. Astronomers have even identified expanding shells of gas and shock fronts around the region, evidence that the massive stars are triggering new rounds of star formation as their energy sweeps through the surrounding molecular cloud. This makes Sh2-171 a fascinating laboratory for understanding how clusters of stars form and evolve, as well as how stellar feedback shapes the environment to spark the next generation of stars.
Notable Features and Fascinating Facts
In wide-field images, the nebula complex’s curved shape has earned it the nickname “Cosmic Question Mark,” since the glowing loops of NGC 7822 and dark gaps resemble a question mark in the sky.
Another whimsical moniker is the “Teddy Bear Nebula,” a name that originated from an astrophotographer’s impression that the bright central region, with its two shining stars, resembles the face of a teddy bear staring back from space.
Aside from these visual nicknames, Sharpless 171 holds genuine astrophysical distinctions.
Its central O-class star (BD+66 1673) is one of the hottest stars known within a few thousand light-years of Earth, part of a binary system and radiating so intensely that it profoundly shapes the nebula’s appearance.
The dramatic pillars and filaments of Sh2-171, sculpted by this star’s energy, not only create a breathtaking vista for observers but also mark regions where new stars may be condensing. Such features, combined with the nebula’s vast size, make Sh2-171 a prized target for astronomers and astrophotographers alike. Capturing this object often requires many hours of exposure time, but the result reveals a rich tapestry of interstellar clouds and young stars in all their glory. Indeed, the stunning visuals and scientific intrigue of Sh2-171 have made it a popular showcase for cosmic photography and a captivating example of how massive stars can transform their surrounding environment.
The Spider Web of Dust - LDN 1268
The image above was cropped and framed in such a way that the dark spider web of dust, known as LDN 1268, is captured in the upper right quadrant.
Lynds Dark Nebula 1268 (LDN 1268) – a dense dust cloud which lies roughly at RA 00ʰ00ᵐ, Dec +67°27′ (J2000), near the edge of the Cepheus Flare molecular complex. It is also cataloged as Yonekura’s CO Cloud 104 and TGU 774 in modern surveys.
Morphologically, LDN 1268 is an absorption nebula – a dark molecular cloud whose tangled, filamentary dust lanes obscure the background glow.
Spanning about 27′ across (≈0.5°), it stands out in photos as a web of opaque “silhouettes” against the surrounding Hα emission of Sh2‑171. This dust network is physically part of the NGC 7822 star-forming complex and is being sculpted by the intense UV radiation from the young OB stars of the Berkeley 59 cluster at its center, as described above. In particular, BD+66 1673 (an O5V star with a temperature of ~45,000 K) is one of the primary sources illuminating the nebula and carving out its pillar-like dust structures.
Astronomically, the dark cloud was first recorded by Beverly Lynds – it appears as LDN 1268 in her 1962 Catalogue of Dark Nebulae – while the broader glowing nebula was indexed as LBN 589 in Lynds’ 1965 Catalogue of Bright Nebulae (Sharpless 171).
With such a low surface brightness (Lynds class ~6, i.e., barely detectable), this nebula is very faint, making it challenging to observe except in long-exposure images. Indeed, LDN 1268’s wispy, dusty web only emerges clearly in deep astrophotography (especially narrowband Hα) where the high contrast reveals its silhouette.
Modern studies show that this cloud is a genuine star-forming clump: CO surveys identify a molecular cloud at its location, and at least a few protostars are embedded within LDN 1268’s dust (≈3 young stellar objects are cataloged), indicating ongoing star formation inside this dark nebula.
Annotated Image
This annotated image was created with the ImageSolver and FinderChart scripts in PixInsight.
The Location in the Sky
This annotated image created with ImageSolver and FinderChart Scripts in Pixinsight.
About the Project
Planning and Weather
The data for this target were collected during the last lunar cycle, when we had a spate of five fairly clear nights.
Some of the details here are the same as for my previous projects, NGC 7380 - The Wizard Nebula, and SH2-157 - The Lobster Claw Nebula, so I will repeat that section here:
Finally, we have those wonderfully long fall nights with almost 11 hours of darkness!
During the last lunar cycle, I ended with five clear nights to capture data. However, on four of those nights, the weather apps indicated that it would not be very clear. In the past, this would have been enough to have me skip the night. It did not sound like it would be worth the effort to set up all that gear! But now that the observatory is up and running - I have no gear to set up! Yay! This means I am much more willing to go after those questionable nights.
I have an astro friend who is a weather buff (I’m looking at you, Gary Opitz!). Gary is an accomplished astrophotographer, and he scans the weather, consults government weather satellite data, and makes his own estimate of how the night will go. He also shares that info with our small local group of astrophotographers and even gives us updates throughout the night. How great is that!
The apps told me it would be a questionable night, but Gary said our chances looked good - so on Gary’s word, I went for it!
I ended up with four nights that were clear all night and one that was good for half a night.
I never know how the weather will go, so I typically research objects I can shoot with each scope - just in case.
As part of my search, I was reviewing the Sharpless Catalog and came across SH2-171. I was not familiar with it, so I thought it had a lot of interesting details, so I added it to my target list. When it was time to allocate targets to scopes, I had made some assignments, but I had not yet chosen something for the AP130. Now the AP130, with a f/ratio of 8.35, is not the best for a faint nebula with dark dust detail, but I needed something for that scope, so I chose this target. While not ideal, I thought that the longer focal length would provide an interesting field of view for some of the structure seen in this target.
This was a new target for me — or so I thought. I believed that all the way through capture and processing, but the spidery web of dark dust looked strangely familiar.
So I did a deeper search on SH2-171 (which is what I do after processing and as I prepare the write-up for the project), and lo and behold - SH2-171 is an object that is part of the NGC 7822 - The Question Mark Nebula. This is a famous and very large target that I had shot before in October of last year!
Not new at all! But at least I had a different image scale and composition on this one, and a lot more integration
I learned that SH2-171 was also known as the Teddy Bear Nebula. I had a hard time seeing that. But if you rotate and the frame is just so, you can begin to see the shape of a face with two bright stars as the eyes:
Can you see a Teddy Bear in this composition?
I could have gone with this composition, but I didn't like the way the spider-web dust feature was cut off, so I shifted my final crop to include it (as you will read later on).
The First Attempt
Here is the prior project if you’d like to dig into that more:
NGC 7822 - The Central Portion of the Question Mark Nebula - October 2024
During the cloudy months of February 2024, when I was bored with the lack of new data, I decided to take another crack at the old data and see if I could improve it. Same data, just new tools (starless processings, RC_Astro wonder tool, etc). You can read about that effort below:
SH2-157 Reprocessing Project in 2024
Here is that image for your convenience:
My first attempt with this target was done in Oct of 2024. The area for this current image can be seen in the lower right quadrant.
Data Collection
Data was collected on the nights of October 16, 17, 26, 27, and 28, 2025.
The nights were cold enough that I could set a camera cooling target to -15 degrees C, and I knew the cameras could handle it. I set things up to do 300-second narrowband exposures with a camera gain of 100.
The NINA sequence handled things very well, and my tracking looked consistently good.
My comments from the last post fit here as well, so I will repeat them:
I find that I spend very little time in the observatory now on these cold nights. I go there to open the roof and uncap the scopes. Then everything else is handled remotely from my nice warm astro man cave. From there, I connect the devices to NINA and kick things off. That’s about it. NINA uses Pushover to send me alerts if necessary. I have a sofa in my Astro Man Cave, so I sleep there and check on things if I get a Pushover notification or if I am up for a bio-break. In the morning, I go back to the observatory, cap the scopes, and close the roof!
On two of the nights, I experienced frost, and each night we had a significant amount of dew. Fortunately, my anti-dew strips handled that perfectly. That was not true on all of my scopes, and I share that tale when I get to those images.
The moon was getting bright on the night of October 28th, but set relatively early. However, I knew that the next night, the moon would start causing problems with my data collection, which was nearing its end. Additionally, rain had moved into the area, and there was no further opportunity for data capture.
On the night of Oct 29th, I collected all of my calibration data, and with that in hand, I was ready to process this image.
Processing Overview
The processing for this image turns out to be very similar to my previous project, except for the fact that I did not collect data for RGB stars. So, the stars would have to be “cleaned up” Narrowband SHO stars.
I decided against Drizzle processing as I thought the base resolution was enough to do justice to this target.
I blinked the data and removed a very small handful of frames due to thin clouds. Even after this, I ended up with 33.5 hours of integration!
Since this project involved only Narrowband data, I used my standard processing workflow for this case. You can see a high-level view of this workflow in the diagram below.
My typical SHO Starless Workflow with SHO stars.
The processing was very similar to my last two projects, only this time there was no RGB star data. I used a Seti Astro Script that attempts to make SHO stars look more like RGB stars - that, plus some other tweaks, made the stars look reasonable.
One of the things that I really wanted to emphasize was the pillars in this image. Based on how they looked, I really wanted to use some tools in the Photoshop Raw Camera Filter tool to enhance them. So I exported the SHO starless image when I was done working on it in PixInsight and saved it as a 16-bit TIFF image. I then imported it to Photoshop, used the lasso with a 100-pixel feather to select the various pillars, and then ran the Clarity, Texture, and Dehaze effects to clean them up a bit. I then saved the image back to a TIF image, loaded it back into Pixinsight, and then used that image as the basis for integrating stars back in.
The final image, however, left me disappointed. There was just something about the composition that didn't work for me.
Here was that first version of the image:
The original composition of the image.
I experimented with various image orientations and crop aspect ratios, and ultimately decided that rotating the image clockwise 90 degrees and then adjusting to a 4:5 aspect ratio yielded the best results. I framed the crop so that the pillars were prominent, and then I worked to keep the spider web of dust in the upper right quadrant within the frame.
The final compositon.
Detailed and Annotated Image Processing Walkthrough
Typically, I conclude one of these imaging projects by documenting the processing steps I used on this image. But this section can make the overall post very large and, at times, slow to load.
I am now creating a secondary, standalone page to hold this information. You can access this page by clicking the link below. Returning to this page is as simple as clicking the back arrow in your browser or selecting a different menu option at the top of the page.
I hope you like this new format!
Hit the Link below to see the detailed image processing walkthrough page for this Imaging Project!
Final Results
I’m quite pleased with the definition I was able to provide for the pillars and the final composition of the image. Here are some close-ups of some of those pillars:
Pillar Detail
Pillar Detail
Pillar Detail
One thing I was not as pleased with was the darkness of the dust regions. I tried several techniques to lighten these areas, and it seemed that I could only take it so far before I started to create an unnatural result. So that is one area where I am still not satisfied with the image. I was able to lighten them a bit, and I think that helped.
The Dark Spider web detail - I wish i could get this better!
At the end of the day, the dust is a dark nebula feature, and it seems like it was just this year that I started to deal with dark nebulae in an extremely detailed manner, and I am still learning how to bring out the best in such a feature. If any of you have techniques that you use successfully, I would love to hear from you!
More Information
🔭 Target Details
NASA APOD — NGC 7822: Cosmic Question Mark (2021-10-13) – Overview of Sharpless 171’s star-forming nebula, noted for its bright pillars and hot young stars illuminating a “cosmic question mark” shape ~3,000 light-years away in Cepheus.
SIMBAD — Sh2-171 – Coordinates, identifiers, and basic data for Sharpless 2-171 (also cataloged as part of NGC 7822 and Ced 214), an H II emission nebula with an embedded star cluster.
Aladin Lite — Sh2-171 field – Interactive sky atlas view of the Sh2-171 region (zoomable; change surveys or add catalog overlays to explore stars and nebulosity in Cepheus).
IRSA Finder Chart – Multi-survey finder tool (enter “Sh2-171” to compare optical DSS plates, infrared 2MASS/WISE images, etc., of this nebula’s field).
Wikimedia Commons — Sh2-171 – Collection of freely usable images of NGC 7822 / Sharpless 171, including wide-field mosaics and close-ups (useful for outreach and educational projects).
📜 History & Naming
Sharpless Catalog (H II Regions) – Wikipedia – Overview of Stewart Sharpless’s 1950s survey of 313 emission nebulae (H II regions). Sharpless 171 appears in the second edition (1959) as Sh2-171.
Sharpless 1959 ApJS — Catalogue of H II Regions – The original published catalog (Astroph. J. Suppl. 4:257), listing Sharpless 2-171 among hundreds of nebulae north of –27° declination. Provided fundamental identification and coordinates for Sh2-171 in 1959.
NASA APOD — Sharpless 171 (2008-10-18) – Astronomy Picture of the Day showcasing the “cosmic pillars” of Sharpless 171. Notes that this star-forming region is entry 171 in Sharpless’s famous 1959 catalog, highlighting the nebula’s catalog heritage.
Deep Sky Corner – NGC 7822 (Sharpless 171) History – Details the discovery and naming: first observed by John Herschel in 1829 (added to the NGC as 7822), later cataloged as Cederblad 214 in 1946, and included by Sharpless in 1959. Explains ambiguity in usage of NGC 7822 vs. Sh2-171/Ced 214 for parts of this Cepheus nebula.
🔬 Science & Observations
Mid- to Far-Infrared Spectroscopy of Sharpless 171 – Okada et al. use ISO’s spectrometers to map the ionized gas and photodissociation region in S171, measuring key fine-structure lines and showing how overlapping PDRs along the line of sight affect [O I] and [C II] emission.
Expanding Shells around Young Clusters – S 171 / Be 59 – Detailed A&A study of ionized shells and neutral material around Berkeley 59 and Sh2-171, examining gas kinematics, shell expansion, and evidence for triggered star formation in the complex.
Photometric Search for Variable Stars in the Young Open Cluster Berkeley 59 – Time-series CCD study that identifies variable stars in Berkeley 59, constraining stellar ages, circumstellar disks, and ongoing star formation closely tied to the Sh2-171 region.
Stellar Contents and Star Formation in the Young Star Cluster Be 59 – Multi-wavelength analysis of Be 59’s stellar population, deriving an IMF, distance, and age distribution, and presenting evidence for sequential and possibly triggered star formation within the Sh2-171 / Cepheus OB4 environment.
Rotating Elephant Trunks – Gahm et al. investigate twisted “elephant trunk” pillars in NGC 7822 and similar regions, deriving masses, densities, and rotation signatures in dense gas filaments sculpted by OB-star feedback.
💡 Interesting Facts & Outreach
Sky & Telescope – “Teddy Bear Nebula” in Cepheus (Sh2-171) – An astrophotographer’s take on Sharpless 171’s appearance. The author notes that the nebula “looks like a teddy bear” peering from space – two bright stars serve as its “eyes,” with round, reddish loops as “ears” and a dark, V-shaped dust lane for a mouth, giving this emission nebula a whimsical nickname.
AstroDoc — Cederblad 214 (Sharpless 171) – Outreach-oriented summary of the brightest part of Sh2-171. Explains that Ced 214/NGC 7822 lies ~2,500–3,200 light-years away in Cepheus. The nebula’s glow comes from ionized hydrogen (with traces of oxygen emission) energized by the young open cluster Berkeley 59 at its center. Includes an image and notes by astrophotographer Ron Brecher, describing the red and blue-green hues of the nebula and its context in the wider Cepheus clouds.
Astronomers Do It in the Dark — Annotated NGC 7822 & Ced 214 – An annotated wide-field mosaic of the Sh2-171 region. It labels the fainter NGC 7822 nebular arc and the brighter core, Ced 214 (Sh2-171). The accompanying description highlights key features: the young cluster Berkeley 59 at the heart of Ced 214, one of the hottest nearby stars, BD+66 1673 (O5 V), which illuminates the nebula’s interior, and numerous Bok globules and elephant-trunk pillars visible in silhouette. This provides a great visual guide to the nebula’s structure and star-forming features in an amateur image.
Capture Hardware
Scope: Askar FRA400 72mm f/5. 6 Quintuplet Air-Spaced Astrograph
Focus Motor: ZWO EAF 5V
Guide Scope: William Optics 50mm guide scope
Guide Scope Rings: William Optics 50mm slide-base Clamping Ring Set
Mount: ZWO AM5
Tripod: Custom Steel Pier - New
Camera: ZWO ASI1600MM-Pro
Camera Rotator: Pegasus Astro Falcon Camera Rotator
Filter Wheel: ZWO EFW 1.2 5x8
Filters: ZWO 1.25” LRGB Gen II, Astronomiks 6nm Ha, OIII,SII
Guide Camera: ZWO ASI290MM-Mini
Dew Strips: Dew-Not Heater strips for Main and Guide Scopes
Power Dist: Pegasus Astro Powerbox Advanced
USB Dist: Pegasus Astro Powerbox Advanced
Polar Alignment
Cam: PoleMaster
Computer: Mele Quiert-4C Fanless microcomputer running Windows 11
Software
Capture Software: PHD2 Guider, NINA
Image Processing: Pixinsight, Photoshop - assisted by Coffee, extensive processing indecision and second-guessing, editor regret, and much swearing…..
Version 2.1 of my Askar FRA400 Platform consists of a switch to a steel pier in the Southeast corner of my new Whispering Sies Observatory. Also changed was the computer from a laptop to a new Mele Quieter 4C mounted on the pier.