Planetary Nebula M1-64 (PK64+51.1)

A YouTuber (Tsula's Big Adventures) recently posted a video about trying to find a small planetary nebula known as M1-64, an object that she referred to as "The Little Ring Nebula." She made several attempts to find it with various telescopes, and when she finally was able to see it through the eyepiece of her 15-inch Dobsonian, she made a sketch (above, left side). I was curious about M1-64, so I took a picture of it tonight (right side), to find out what it looks like in my 12-inch telescope. I added the lines to some asterisms to make the comparison between her sketch and my photo easier.

The sketch Tsula made of the starfield surrounding M1-64 is quite good, but it reveals some of the pitfalls of astrosketching. Many years ago, whenever you'd come across an amateur astronomer's sketch of a celestial object in the astronomy magazines, it usually would be accompanied by a photograph of the same object. But often times, the emulsion-based photograph was a deep (or burned-out) exposure of the object, revealing much more detail than could be seen in the eyepiece. Sometimes the burned-out portions hid details that were included in the sketch. And in many cases, the photograph was mirror reversed or inverted or printed at a different scale than the sketch, making it difficult to directly compare the work of the visual artist to that of the photographer. It was nearly always an unfair comparison. Not only that but often times the sketch was printed on a different page, so that readers would have to turn a page to compare the sketch to the photo. 

As an example, take a look at the March 1983 issue of Astronomy magazine. There are sketches of M 99 and NGC 4567/8 on page 38, and photos of them on pages 36 and 37, respectively. Below is the sketch of M 99 and its accompanying photo. Not only do you have to turn a page to compare the sketch with the photo, but you have to rotate the photo 90 degrees to the left to match up the stars. And when you do that, the orientation of the prominent spiral arm in the sketch doesn't match what appears to be the prominent spiral arm in the photo (with respect to the line of stars). Perhaps the magazine put the sketch on a different page than the photo, and added the rotational mismatch, so that the inaccuracies of the sketch wouldn't be noticed. For the record, the proper orientation of M 99 in the sky is such that the line of stars extends to the northeast of the galaxy (toward the 10 o'clock position), so neither representation of the galaxy in either the sketch or the photo, as published in the magazine, is correctly oriented with a star chart. 

© Astronomy magazine, March 1983

Below is the comparison of the sketch of NGC 4567/4568 to the photograph. Not only do you have to flip the page to make the comparison, but you also have to rotate the photograph by 180 degrees to match the views. And when you do, you'll notice quite a few missing stars in the sketch! For the record, the sketch is properly oriented to match the cardinal directions of the sky (north is up, east to the left), and the photo was printed upside down. Once again, you have to wonder why they didn't make it easier to see the comparisons. Were they simply trying to hide the inaccuracies of the sketch? (Hint: the sketches were drawn by the author of the article, who would later become the Editor in Chief)

 

© Astronomy magazine, March 1983

Whether it was magazines or books, you rarely (maybe never) saw a sketch and a photo side-by-side, at the same scale, same level of detail, and rotated to match each other as closely as possible. I got the impression that we were supposed to develop an expectation that what you see through the eyepiece is somehow vastly different than what cameras pick up. This is not true, however. A good sketch can neatly match a short exposure of the same field taken by a camera. 

The camera doesn't lie, so when there are significant differences between a photo and a sketch of the same target, the astrosketcher's drawing skills are naturally called into question, and worse yet, the sketcher may be accused of "making up" what they saw in the eyepiece. But the main problem is that when we compare someone's sketch to a photograph, we tend to hold the sketch to the standard of a photograph. We demand that the sketch be exact, so that it looks like the photo. And this is unrealistic. When we attempt, for instance, to make a sketch of someone's face, we usually have a very difficult time making our sketch look exactly like the person we're sketching! So, imagine drawing groups or asterisms of stars as pinpoints of light and of varying brightnesses. We see a triangle of stars or a quadrilateral of stars. A slight mistake in the angles changes the geometrical shape drastically, even though in our minds, what we drew was a fairly close approximation of what we observed in the eyepiece. 

A sketch isn't usually intended to be a perfect match to a photograph. Nor should anyone else expect it to be a perfect match. It need only be representative so that you can look at the photo and see which stars and features the sketcher likely saw through the eyepiece. Some sketchers with a lot of practice can achieve sketches that closely match photographs. But for the rest of us, we can only do our best in the environmental conditions (air temp, wind, and humidity) and circumstances (neighborhood distractions) that we were working in. Some stars go unnoticed in the eyepiece, even though, in the photograph, you get the impression that they should have been seen by the sketcher. And some stars were easily seen by the sketcher but were simply forgotten to be put on paper in the drawing process. Other stars are left out on purpose because there were just too many stars to draw! Sometimes you just can't draw every last star you see. 

To be fair, astrosketching is a very difficult skill to acquire. Like astrophotography and image processing, there are some who can do it extremely well, and some who do it not so well! Sketching takes a lot of practice and the difference between doing it very well and doing it not so well is simply a difference in desire. What is your goal? Do you want to make all your sketches look like photographs? Then you can work on techniques and find ways to get it done. Do you just want to create a quick-and-dirty sketch to serve as a printed record of your observations? Well, then maybe you don't need or want the added stress to get it exact. Astrosketching, like astrophotography, is after all, a hobby to be enjoyed in any way that satisfies your goals.

But for the uninitiated, when you look into the eyepiece and see various star patterns or mini-asterisms, drawing them correctly positioned within an eyepiece field-of-view circle on your sketchpad is not as easy as it sounds! You must not only nail down the stars of each small asterism, but you also then face the challenge to realistically orient all of the asterisms, not only to each other, but also orient them to the field stop (the field-of-view circle of your sketching area). And if you're using an alt-azimuth mount, the entire eyepiece field is rotating as you draw. Worse yet, if your telescope doesn't have tracking motors, you have to keep repositioning the telescope's aim as you draw. You have to do all of this while holding a sketchpad with one hand, your pencil with the other, and somehow shining a dim red light on your sketch so that you can see what you're doing without ruining the dark adaptation of your eyes.

There are some tools and techniques that sketchers can use to make sure their asterisms are properly drawn, their star brightnesses are appropriately binned, and the size and shape of extended objects (star clusters, nebulae, and galaxies) are represented with fidelity. But the most difficult task of the astrosketcher is to avoid the temptation of drawing details that they didn't see. Sometimes wishful thinking gets the better of us. We know something is supposed to be there. After staring at the field for prolonged periods, we might even think we detected something. Everyone who spends a lot of time and effort to hunt down a faint celestial object really wants to be able to declare that they saw it. Some observers joke about using the technique of "imagined vision" in addition to averted vision. Being able to locate and see the target requires good observational skills, as well as having a telescope with ample light-gathering power and magnification. And both of these qualifications are limited by the sky conditions, to include sky brightness, as well as good "seeing." Sometimes faint targets lie in the fringes of our detection limits, and we just have to be honest with ourselves, as to whether our observations were successful or not.

Small and faint targets like M1-64 require persistence. Tsula demonstrated her persistence by making attempts to find M1-64 on several nights, with different telescopes, eyepieces, and filters. When she finally saw it, by using her largest light bucket, she made a sketch, proving that she saw it. Then she went back to look at it again with her smaller telescopes. In the end, she was able to see M1-64 through her 10-inch Dobsonian. 

A frequent occurrence amongst visual observers is that once you finally see a stubbornly invisible object with certainty and become familiar with its appearance in the eyepiece, you can usually go back to it on a different night, with sometimes worse sky conditions, lower power, and smaller aperture, and find it with ease. This leads to the apparent contradiction we often read in observer reports. Someone says, "You can see this object in a 4-inch refractor," but when you go out there and struggle to find it with your 8-inch or 10-inch telescope, you will strongly disagree with the other observer and feel like they lied to you! You'll question your own observational skills or the quality of your telescope. But it's not a lie. With the proper skills and dogged persistence, a lot of deep-sky objects can be detected in unexpectedly small-aperture telescopes.    

Although I have a 10-inch Dobsonian telescope that I can set up and use in the back yard, I find that standing or sitting out in the back yard at night with my telescope is very annoying. My neighbors are sometimes having parties with loud music and drunken laughter, and they have their bright backyard lights on, which kills my night vision. I hate sitting out there trying to concentrate on seeing faint deep-sky objects, much less sketching them, with all that distraction around me. So, I typically set up my CPC-1100 telescope, HyperStar, and CCD camera, connect it to my home network, and I go back inside, where I search for supernovae all night long, in the comforts of my living room. The camera is not bothered by my neighbors' lights, and I don't have to be subjected to all their shenanigans.

Of course, taking pictures with a CCD camera and the fast f/2 focal ratio of the HyperStar lens allows me to peer much deeper into the universe than looking through the eyepiece of a 10-inch Dobsonian, so you might wonder why I would bother even owning a 10-inch Dobsonian in the first place. But I got my start in backyard astronomy years ago by looking through the eyepiece of my telescope, and there are still times when I'd rather use a Dobsonian telescope to look at something than take a picture of it with the CPC-1100. I like taking up the challenge to find and see difficult objects. And there are plenty of nights when I set up both telescopes. It's nice to have two telescopes, so that I don't have to swap out the HyperStar and camera with an eyepiece. I can be hunting for supernovae with the CPC-1100 and just feel like taking a break to go outside and look at Jupiter and its moons or the rings of Saturn through the eyepiece of the Dobsonian. I'll star hop to my favorite deep-sky objects that I know by heart and renew the surprise of how good they look in the eyepiece, even in the moderately bright sky of the suburbs. After midnight, my neighborhood begins to quiet down and some of the annoying night lights are turned off. I can see the Milky Way in my backyard, so my skies in the outskirts of Tucson, AZ, aren't as terrible as you might think. I can look up into the mountains directly to my east and see the domes of telescopes operated by the University of Arizona, so my sky brightness can't be a lot different than theirs. 

The CPC-1100 at f/2, using the HyperStar lens, turns my 2800 mm focal length SCT into a 560 mm Schmidt Camera. If you know anything about optics, you'll recognize that the HyperStar turns my high-powered, narrow-field telescope into an extremely low-powered and wide-field system, not unlike the field of view captured by a 560 mm camera lens. And admittedly, it's somewhat of a compromise. I give up magnification for "fast imaging." Yeah, I turn my f/10 telescope into an f/2 telescope, so that I can capture faint details of galaxies in seconds, rather than hours. The cost of this is that I give up resolution. If I were to shoot a galaxy using my SCT at its native focal length of 2800 mm, it would literally take dozens of hours to get a reasonable picture, and it would be a very high-resolution image of the galaxy. But the HyperStar lets me get decent results in dozens of seconds, not hours. That's why we call it "fast." The f/2 lens permits short exposures, or "fast results." But galaxies look much smaller at 560 mm focal length than they would be at 2800 mm focal length.

A small 4-inch APO refractor at f/5.6 will give approximately the same field of view as my CPC-1100 at f/2, and our focal lengths of roughly 560 mm will be similar. But the tiny aperture and f/5.6 focal ratio of the refractor will require exposures of many hours, compared to many seconds at f/2 with my system. Additionally, the smaller aperture of the 4-inch will yield an inferior resolution when compared to my 11-inch SCT. 

But compromise is a good and desirable thing. I don't want to take 50-hour exposures! I want my results faster! And I don't care if I'm shooting at a smaller scale. There are lots of large galaxies (or groups of galaxies) and nebulae that need a larger field of view than I can get from an 11-inch f/10 telescope. And for the smaller objects, I just zoom in a little bit in my images. I can resolve supernovae in small galaxies much faster with my CPC-1100 and HyperStar than I can with a small refractor at f/5.6. That makes all the difference. I can shoot more galaxies per night with a "faster" telescope, and shooting more galaxies is the secret to finding supernovae.

The fast optics of the HyperStar and CPC-1100 are also very good for Electronically-Assisted Astronomy (EAA). There are lots of backyard astronomers who appreciate the fast imaging of deep-sky objects. They aren't interested in spending weeks, months, or years to take a fantastic photo of one celestial object. They want to go after thousands of objects. Looking at many of these celestial objects through the eyepiece of a telescope isn't as satisfying as taking a long exposure of them with a camera. But at the same time, the complexity of shooting 50 hours' worth of exposures of deep-sky objects through 3 or 4 filters and then spending days of image-processing before achieving the final result is also unappealing. 

So, EAA enthusiasts go for the "quick and dirty" results. Fast imaging with minimal processing is the goal. We get a better view of celestial objects than looking in the eyepiece, but our pictures can't compare to the sensational images that astrophotographers share on social media.

My picture of M1-64 at the top of this page (right side) shows what these quick and dirty results can achieve. A strict visual observer would have to load their large-aperture telescope into their car and drive hundreds of miles away from the city to find very dark skies in order to see M1-64 this well. On the other hand, astrophotographers wishing to take a better picture of M1-64 than mine would have to shoot many hours of exposures at longer focal lengths to win them an Astro Photo of the Day (APOD).

Below is my full-frame image of M1-64. Click the image to see a larger view. But after viewing the larger image, I recommend right-clicking it and choosing "Open image in new tab" so you can get the magnifying glass and see it at full scale. Zoom in to see if you can see M1-64 near the center of the field. Zoom out to compare the surrounding star field to DSS images online. North is up, east is to the left, just as it appears in the sky.

By the way, below is a picture of Messier 57, the original Ring Nebula. Oddly, M 57 is very nearby to M1-64. If you wish to go after M1-64, it's a very good idea to start your search by aiming your telescope at M 57. From there, you can star-hop to M1-64 using your 8x50 finder scope. My picture below shows M 57 at the same scale as M1-64, the "Little Ring Nebula," above. The only difference is that I cropped it in order to make M 57 appear nice and large without having to right-click it. Unlike the "Little Ring Nebula," I didn't need to stack up a bunch of exposures to get enough signal. This is a single 22-second exposure, and yet you can plainly see its central star. I can't see that central star through the eyepiece of my CPC-1100. 

If you were to take a small telescope (say, a 6-inch reflector) out into your back yard and hunt down the Ring Nebula, M 57, you would find a ghostly ring, resembling a smoke ring blown by a cigarette smoker. M 57's appearance will impress you. When your aim is sure and M 57 shows up in your eyepiece's field of view, you'll be amazed at the size of the smoke ring compared to the pinpoint stars surrounding it. 

Indeed, M 57, the "(Big) Ring Nebula" is a remarkable deep-sky object, worthy of being sought out in your summer night sky with a small telescope. But the "Little Ring Nebula," as Tsula calls it, is tougher. You'll need a much bigger telescope (say, a 10- or 12-inch aperture telescope), and even then, M1-64 will not impress you. In fact, it probably won't even look like a ring. At best, you may only recognize it as a hazy orb, slightly larger than the stars in your eyepiece view. At worst, you may not see it at all, despite a gallant effort, making for a frustrating evening under the stars. 

We live in tough times. More and more night lights are going up in our cities, making our night skies brighter and brighter. That's bad for backyard astronomy. To get to truly dark night skies, we have to drive farther and farther out of town. The experience of visual astronomy (just taking a telescope out at night and looking at celestial targets through the eyepiece) is sadly becoming a thing of the past. We could solve this problem easily by just not adding more outdoor lights across our cities, and by putting shields on our existing night lighting so that our outdoor lights shine downward and not outward or upward. But not enough people care about looking up at the stars, let alone working to preserve our dark skies. It's a losing battle trying to educate our neighbors and city council members about installing proper night lighting that would have less impact on sky brightness. We used to have the high operating costs of night lighting on our side. But now bright LED lights are cheap to operate. Our night skies will only keep on getting brighter. It's very depressing to amateur astronomers, but it's a fact that we must accept. Visual astronomy may one day soon become impossible. Meantime, we may not be able to see much through our telescope eyepieces, but our cameras and filters should continue to cut through the light pollution and allow us to explore the deep sky in our back yards for many years hence.

While we still can, I suppose we backyard astronomers should continue to challenge ourselves by trying to observe faint objects like M1-64. But time is also running out on our opportunities to observe better and more historically important celestial objects than the Little Ring Nebula. Every backyard astronomer should, for instance, locate and observe all 110 of Charles Messier's star clusters, nebulae, and galaxies, and then maybe start working on the Herschel 400. Following that, maybe continue with the rest of the Herschel 2500. Observers and astrophotographers (myself included) have also gone after a few other famous lists, such as the Caldwell objects, the Hickson galaxy groups, and Halton Arps' list of peculiar galaxies.

The more years we spend as backyard telescope enthusiasts, the more important it becomes for us to have something to show for our efforts. In my 50's, I reflected on 30 years of astronomy in my back yard and traveling to various remote locations under dark skies. That's a lot of years, and a lot of nights observing and photographing the heavens, especially after I moved to Arizona where we can have 300 clear nights per year. I was more than a little embarrassed, however, to admit that in those three decades, I had not seen all of William Herschel's discoveries that he catalogued in fewer years, working under the frequently cloudy skies of England! 

I am proud to say that I remedied my situation and used my Go-To telescope and CCD camera to go after them all. It was a monstrous effort to verify (using books and online images) every Herschel object that I photographed and place a copy of each image in my "Herschel_Objects" computer folder. The project took me 12 years to complete. The earliest image is dated 2008 and last image is dated 2020. The folder contains 11 gigabytes of over 1900 images (many of the images contain multiple Herschel objects).

Nobody else cares about my efforts, of course. I didn't try to get an award for my accomplishment from the Astronomical League. It's a personal thing. It was important to me to set those goals and realize them. If anyone were to ask me, "Wow! That's a lot of years as a backyard astronomer! What all have you seen during that time?" it's very easy to quantify my observations. I can simply say with confidence (backed up with my images) that I photographed all the Messiers, all the Herschels, all the Caldwells (observable from my latitude), and so on. Even if no one were ever to ask me that question (and truthfully, no one has, other than me, asking it of myself), it's very satisfying to know my answer. 

So, what is my advice to someone who has a few years of backyard observing under their belt, and they're looking for interesting targets to go after? 

Well, it's simple. Try thinking about yourself in the future, having stuck with the hobby for decades. What can you accomplish that will make you feel like the journey was worth it? Looking back on years' worth of willy-nilly, random observations is probably not going to cut it. And the vast majority of us aren't going to become famous for making some astronomical discovery, or for taking the most awesome astronomical picture ever! What you'll likely find to be deeply satisfying and rewarding is going after collections of celestial targets, like the lists I mentioned above. Or compile a list of your own. Observing or photographing all the items on these lists can take many years, even when you conduct careful planning and work as efficiently as you can. 

Realizing all of this right up front in your journey should provide some direction so that you can start prioritizing your targets as soon as possible. Contrary to popular belief amongst young people, time is NOT on your side!

I don't recommend that you choose just one list, work it to completion, then go on to the next one. Instead, take the time right now to download all the popular lists, to have as a reference. Even if you don't like the idea of "chasing after lists" during this phase of your hobby, when you choose some objects to go after on any given night, take a look at your reference documents and see if your selected targets are on one of the lists. If so, take the time the next day to "check off" from the lists those targets you observed. This way, you'll be working toward completing each list, without even intending to do so. Many years from now, when you might finally feel like you want to complete one of those lists, you'll find that you've already got a good start on it.

Also, I won't go as far as to say, "Don't waste your time observing targets that aren't on one of the major lists," but I do advise giving it some thoughtful consideration. For example, if you come across some target like M1-64 that you heard about on YouTube or CloudyNights, you might decide to take up the challenge. This may cause you to spend many clear nights trying to find M1-64, using many techniques, filters, and different telescopes. Maybe you eventually saw it. Maybe you didn't. Maybe you feel pretty sure you saw it, but just barely. Right now, spending so much time on one object may not bother you. But in the future, it may come back to haunt you. You might one day find yourself three quarters of the way through the Herschel 2500, frustrated by long stretches of cloudy weather, thinking about your advancing years, and starting to wonder if you're ever going to get it done. You'll look back on that week you spent trying to see M1-64 and you'll wish you had instead spent that time going after Herschel objects!

Update 09-13-2025: 

I set up the 10-inch Dobsonian tonight to have a good look at M1-64 through the eyepiece. There was no moon, and I could see the Milky Way stretching down from Cygnus at the zenith through Sagittarius to the south. M1-64 in Lyra was high overhead, just an hour and a half west of the meridian. I figured this was my best chance to get a good view of M1-64. 

For reference, I printed the side-by-side picture at the top of this page with colors inverted (black stars on white background, like a star chart). I used the print as a finder chart and was able to locate the asterisms. The view in the eyepiece of my 10-inch Dobsonian can be described simply as "unimpressive." If I didn't have my photograph to use as a reference, I probably wouldn't have noticed M1-64 at all. But since I had my photo, I knew exactly where to look for the Little Ring. At first, I wasn't sure if I saw anything there or not. But my eyes were not completely dark-adapted, and my scope wasn't quite equilibrated to the ambient temperature. So, I just kept staring into the eyepiece and concentrating on the spot where the nebula should be. As time passed, a very faint "blob" became more and more noticeable. After about 5 minutes, I was no longer in doubt that there was a fuzzball there, a little larger than the stars. And that's as good as it got. I used a 9 mm Televue DeLite at 141X, which was about the highest power I could use to get sharp stars. I could see M1-64 and hold it without the need for averted vision. But it was just a dim, shapeless blob. Not a ring. 

I can't say it was the "hallelujah" moment that Tsula experienced. I detected it. Barely. But I can't say that it was worth going after. Maybe Erika Rix found M1-64 with an 8-inch telescope, and that's great. But "barely detecting" something vs being able to see its features are two different things.

In my humble opinion, the Little Ring Nebula might be a fine object in a 15-inch or larger telescope, but in a 10-inch or smaller Dobsonian, it's a total waste of time! If you want to accept the challenge or test your observing prowess, go ahead! Have a look at M1-64. But if your telescope is less than 15 inches of aperture, take it from me: follow my advice in previous paragraphs and spend your time tracking down more historically important celestial objects! No disrespect intended toward Rudy Minkowski! He's certainly historically important. All I'm saying is that if you're going after the list of Minkowski objects, you probably should be using a 32-inch Dobsonian, at least!