Why Bother?

What is it that causes someone to undertake astronomy as a hobby? I certainly believe that one of the primary drivers is the majesty of the night sky - especially when unencumbered by light pollution. It is a visceral awe that arises from your soul when you behold a sky that is ablaze with stars. 

Milky Way over Blackwater Wildlife Refuge - by Cheryl Kerr

Another incentive is the invitation to ponder the fantastic. We learn of things such as suns collapsed down to neutrons where a pea-sized portion of it would be measured in tons, and we contemplate storms on other planets lasting centuries.

Yet a third enticement is the thought that one might contribute to that body of knowledge. In bygone decades the discovery of a comet was the goal of many a dedicated amateur observer. Others have fastidiously and relentless made magnitude estimates of variable stars, or timed the central meridian crossing of Jovian features. But then the automatons arrived, tireless robotic scopes and orbiting observatories capable of being the eyes on the universe in a way amateurs cannot match.

The perceived loss of relevance is certainly real. Witness the genuine excitement of our community at the prospect of providing exo-planet transit timings to help scientist improve their knowledge about these distant worlds. I fully expect companies like Celestron to soon begin marketing tools to help those who wish to participate in this work.

Planetary observing has been an astronomical passion since my first “real” telescope that enabled me to see features. I started by sketching Jupiter, Saturn, Mars, and Venus to submit to the Association of Lunar and Planetary Observers (ALPO). More recently I’ve taken up imaging as it yields results that are far superior to my aging eyes and artistic talent.

After so many years of just being an ALPO member, I decided last year to volunteer as the coordinator who posts images and sketches from observers across the globe to the ALPO gallery. Twice this week, in email exchanges with individuals who contribute their work to the gallery, I encountered the sense of inadequacy. “It is impossible to keep up with the big guns,” was the lament from one. It can be deflating when comparing one's work to the astounding images produced by amateurs equipped with larger scopes, deeper pockets, and a firm dedication to their craft. Indeed, why bother to capture an image when you know there are others whose work is consistently an order of magnitude better than what you can achieve?

First, I’d argue that self-improvement is never a wasted effort! As you become more familiar with the equipment and software your end result will look better and better. This, in turn, is likely to encourage you to buy that next piece of equipment or program that can push your current boundaries of expertise. You may never reproduce the results of someone like Damien Peach, but that is true with any hobby – from needlepoint to swimming there are dedicated “amateurs” who will always be the ones we strive to emulate.

My Mars images from 2018 and 2020

 

Secondly, you’ll never know when it will in fact be you who witnesses a rare event. It happened to Ethan Chappel two years ago as he was carrying out “lucky imaging” of Jupiter when he recorded a momentary bright flash that turned out to be a boulder-sized meteor striking the planet. He was the only person to capture the event which helps scientists to calculate the frequency of such impacts at Jupiter. If it happened to Ethan (and others over the last decade), it could certainly be you the next time.

A final motivation is that your observation is likely unique. The top gun amateurs are not out there 24x7 capturing video of the major planets. Your photo or sketch can be very useful in determining the drift in longitude of a Jovian cloud feature, pinpointing when and where that Martian dust storm originated, or refining a brightness estimate of an inbound comet. Advancing science is often achieved through many data points – be one of them!

 

Yes, the professionals and leading amateurs have the equipment and resources to provide us with stunning planetary images. But that should not be any reason to rule out the citizen scientist role you can play by persistently going out and reporting on what you see to organizations like ALPO. Keep refining your skills and keep looking up – who knows what opportunity for discovery you might encounter? 

 

 

Second First Light

Compared to half a century ago we pretty much live in an astronomical COTS time. The vast majority of amateurs peer through equipment that is massed produced. Attending a BAS star party back in the 70s and 80s, one would find a fair number of the telescopes were fashioned by their owner. They ground the mirrors and constructed the mounts, displaying a range of frugality and craftsmanship in their implementation. Many clearly had taken "shop" as part of their secondary education and were comfortable turning out custom parts for their scopes. 

One of those individuals was Charlie Cyrus who built a 10" Dobsonian. I will always remember the first time I peered through the instrument at M13 - I was blown away at how well it resolved the stars compared to my 6" telescope. When looking at the planets it always provided crisp views that spoke of the hours he had poured into sculpting the glass to his standards. Charlie was the epitome of an ATM.

When Charlie passed his good friend and fellow BAS member Dr. Richard Pembroke became the steward of his telescope. Richard was a passionate, respected amateur astronomer and well connected to the community of observers. As he contemplated downsizing in retirement he asked if I was interested in having Charlie's telescope. I immediately said yes even as I pondered how I could explain to my wife that I had another telescope in the garage. 

For about 15 years I used the Cyrus scope as often as I could. Its additional aperture allowed me to track down multiple additional Herschel 400 objects and pick out more details among Jupiter's clouds and Mars' surface. It accompanied me to many Stellafane visits and Tuckahoe star parties, creating memories along the way. But time and use took its toll, and eventually the wooden Dobsonian mount became too feeble to properly support the optical tube assembly (OTA). I could almost hear Charlie saying, "OK Jim, it's your turn now to use some ATM skills to restore it!" 

And so I set off on what would turn out to be a multi-year endeavor to give Charlie's scope continued life observing the heavens. I elected to replace the Parks tube that housed the mirrors since the focuser (which Charlie had made) was no longer usable with too much slop. Lacking machine shop skills, and no friends with that talent, I calculated that a sturdy "Sonotube" would be best since it was a material I could work with. I ordered a long, sturdy tube - thicker than a Sonotube to ensure support - and cut it to size. This was like pulling the thread that unzips the seam, because now the machined mirror cell had to be adapted to the new tube, or a new one made. It seemed that I would clear one hurdle and then have yet another technical challenge to address. But finally the new OTA emerged under my hands. 

One of my primary objectives was to have the scope on a mount where tracking was feasible. My grand scheme was a Dobsonian tube cradle that could have a mounting plate affixed to it, permitting the OTA to move from Dobsonian rocker box to my Orion GEM, offering the best of both worlds. I made several attempts at it before finally facing the fact that it was not going to work - the Cyrus OTA was just too heavy. 

Growing tired of having the OTA but no mount, I elected to contract the task of creating a Dob mount. I coordinated with a shop out in California about a year ago and ordered one of their products, hoping that I could add a Losmandy mounting plate to the tube cradle to permit me to attach it to my sturdier CGX-L GEM that I had acquired. I had hoped to have it by the Mars opposition last October, but that deadline came and went. Maybe by the Grand Conjunction in December, but that, too, came and went. Finally I received it in April and assembled the new Dob for the Cyrus scope.

The mount seemed adequate and I believed it would work out as I placed the OTA into its cradle. One issue I noticed quickly was that even though I had added additional felt liner, the tube would still slip down under its own weight. But that felt like a problem that could be fixed. With the Moon almost full it served as a convenient target to verify if the optical train was properly configured. I found that the mirror needed to be set back down the tube in order to achieve focus, but again, a task that was very doable. 

Almost there! Or so I thought. The next free weekend I set about repositioning the mirror and adding additional felt when I noticed that the laminate on one of the wooden altitude bearings was separating. Indeed, the entire thing was coming loose and breaking. I couldn't believe it and contacted the vendor. Long story short, there would be no resolution from this person, and given the delays in receiving it I was not about to ship it back and have another year pass waiting and hoping for this individual to make it right. One benefit of my heart attack has been making it clear to me that every day counts.

Laminate Separation

I decided to take off the Friday before the July 4th holiday and dedicate that 4 day weekend to making a tube cradle with an attached Losmandy plate that could support the OTA on the sturdier mount I had purchased - no more excuses! In some regards it reminded me of software development in terms of the life cycle - design, create, test, remediate defects you uncover during testing and try again. Finally, in the pre-dawn hours of July 5th, I got a true "first light" for my Cyrus scope restoration by imaging Jupiter for an hour. The detail it provided, along with the exciting prospect of having this wonderful instrument back, made it all worth while!

 

And now the refinement process has to happen, steps to take to make the telescope easier to use (because a telescope that requires a lot of effort to set up for a session does not see as much starlight). Inspired by some photos of HAL member Victor Sanchez's setup, I used last weekend to craft a "dolly" so that the entire rig can be rolled in and out of the garage. Next up will be adding a dovetail to attach a finder scope and hopefully a paint job to make it look a little more polished. The biggest lesson in this journey has been a better appreciation and respect for the talent, effort, and ingenuity that an ATM puts forth into their telescope - truly a labor of love from which I have benefited greatly. Thank you Charlie for leaving behind such a gift - I'm proud to be its steward and hope I'll pass it to another generation of stargazers one day!

Lessons from an Owl - Part II

 As noted in the prior blog, I recently spent an enjoyable evening from my driveway tracking down the Owl nebula. It was a challenge to discern it amid Towson's ample light pollution with my modest 80mm refractor, but that made the accomplishment all the sweeter. It also made me revisit a wonderful book, Visual Astronomy of the Deep Sky by Roger N. Clark to refresh my understanding of the science behind the successful observation.

You don't have to be an amateur astronomer to grasp the concept of dark adaptation - we've all experienced how over several minutes you can begin to pick out dimly lit objects in the bedroom once the lights are doused. While the widening of the iris to take in more light helps, it is the gradual accumulation of "visual purple" that is the principle actor, amplifying the sensitivity thousands of times. It takes about 30 minutes to build up a full compliment of the chemical in the eye's rods & cones, and it can be undone by a brief encounter with a strong light source (even a bright star as viewed through the eyepiece). So lesson one for the suburban astronomer when stalking the Owl is to be as diligent as possible shielding your eyes once you have some night vision. A shroud of some sort to drape over your head to block out the neighbors' lights is an inexpensive but useful tactic.

Another interesting finding reported by Clark is that the eye actually does have an integration capability when it comes to gathering light. It's certainly not like film or CCD sensor, but "for the detection of the faintest objects, the light must accumulate on the retina for around six seconds." This proves yet again that patience and discipline play a key role for capturing faint fuzzies, requiring that you study a section of the field for several seconds rather than looking at a new spot if you do not immediately find something. It's actually a bit harder than it sounds - I know my tendency is for my eye to want to dart around the field in search of my target.

Averted vision is well known among observers. The eye's improved sensitivity to faint light outside the direct area of focus (the fovea) is due to a higher density of rods in that area of the retina. Clark provides diagrams that show the population of rods across the field of view, as well as pointing out the literal "blind spot" we all have. When you're behind the eyepiece it helps to know where this rod dense region is rather than simply looking askance of your suspected DSO. For the record, it is "8° to 16° toward the nose from the center of vision."

One of the more misunderstood concepts is the relationship of magnification to detecting a faint object. You often see people posting on FB or boards that you want the lowest magnification because that gives the brightest image. But that also gives you the brightest background (light pollution) as well, and anyone who has bothered to bump up the magnification of a misty open cluster can attest that the fainter stars are easier to see under that higher power. Many assume that the increased magnification darkens the background sky and makes the object easier to pick out - yet the object is also darkened, so that does not make sense. Clark explains with several graphs how the size of the object plays a significant role in our eye's ability to pick out a faint object. In fact, there is actually an optimal magnification for an object given its size, brightness, and scope aperture.The author kindly provides a handy appendix that list many DSO and their optimal magnification. For M97 and my 80mm Vixen the suggested magnification would be 140x, and indeed I had my best view at 150x. 

To wrap it up, I bagged the Owl by applying most of Clark's suggestions: guard your night vision to the best of your ability, patiently study one area of the view with averted vision for 10-15 seconds, and don't hesitate to increase the magnification if your first inspection turns up no result. If you are a fan of visual astronomy I thoroughly recommend you get a copy of Visual Astronomy of the Deep Sky. He truly treats the topic as a science as well as walking you through how to study an object to get the most from it. Because it is out of print you should be prepared to pay a premium price (north of $100 for a copy available on Amazon). Of course, an even better option if you are a member of HAL would be to check out a copy from the club library as noted here. With star parties resuming this summer it's a great time to learn more about the science and practice of visual observing!

Lessons From an Owl - Part I

For a while now I have been revisiting the objects on the Astronomical League's Urban list using my 80mm Vixen refractor from my driveway. This began out of my curiosity as to what an observer with a modest scope amid significant light pollution might be able to see. Certainly the big & bold stuff would be easy pickings, but after that, where's the limit as to how subtle an object can be bagged?

Bortle 8 Skies from Towson

 

Of course, the first benchmark on visibility that any amateur astronomer invokes is the brightness of the target, i.e. it's magnitude. There are handy charts and online tools that calculate the faintest magnitude star that one can possibly see for a given telescope aperture. Out in the field there will be a host of other factors that influence that value - the most obvious one being just how aggressive the artificial sky glow is at your location. But things from the condition of the scope (clean optics, alignment) to your age will also affect your limiting magnitude.

As the observer quickly learns, magnitude is only half the story when predicting visibility of a non-stellar target. Size is a critical consideration since the given magnitude is going to be more or less spread out across the object. This is why although galaxy M33 is one of the few galaxies above 6th magnitude, it is also notoriously hard to spot from suburban settings because it has that light spread out over 60'x30'. Surface brightness, the average per arcsecond (or arcminute) magnitude for the target, attempts to level the playing field when  ranking the relative brightness of a deep sky object.

Based on some of my observations thus far (below), M97, the famed "Owl" planetary nebula located in the bowl of the Big Dipper, presented as a DSO that might be doable. Some objects fainter than its 21.88 surface brightness had been visible, while one brighter specimen - reflection nebula M78 in Orion - had failed to materialize. Could I capture the Owl? 

The first spring evening of 2021 turned out clear and with reasonable temperature. I decided to set up for an observing session, even with a waxing fat crescent Moon hanging in the sky. Since this evening coincided with the first HAL public virtual star party I set up my phone nearby and listened in as I went through the alignment process. Jim Johnson provided some celestial mechanics relative to the Moon as it traverses the ecliptic throughout the year while getting it centered for viewing. Victor Sanchez took a turn and shared a colorful image of the Orion Nebula using his equipment. It was as if I had the company of fellow observers as I embarked on my quest for the Owl.

https://freestarcharts.com/messier-97

 

With a good alignment obtained I drop in my 9.7mm Plossl with UHC filter and bid the mount to slew over to Dubhe to ensure sharp focus, and then slip over to the nearby Owl. As expected, there was nothing there at first glance except a few dim field stars. Time to apply the tricks and techniques that I've picked up over the years. First up is draping a dark pillow case over my head to shield my eyes from neighbors' house lights. Then it is a matter of just relaxing and allowing my dark vision to gradually improve. I shift my focus to various points in the field so that my averted vision has multiple opportunities to notice anything. When that fails I turn to using the controls to nudge the field a bit, hoping the well camouflaged Owl face will give itself away if it moves slightly. 

After perhaps 10 minutes of effort it is time for the next tactic and I boost the magnification slightly with an 8mm TMB eyepiece. I again start off at Dubhe for a focus check and then swing over to where M97 should be. The same now familiar field stars are there to greet me while the planetary still refuses to emerge. I begin my stalking routine again and then it happens. I think I see something there to the right of the three brighter field stars! I spend the next five minutes directing my focus to various points in the field in an effort to give my averted vision its fullest advantage. Finally I am convinced enough that the faint, shapeless specter is indeed M97 and not just imagination. Success!

The elusive Owl Nebula captured!

 As I work up a sketch of the Owl I notice that it becomes a little easier to see. This is likely because drawing an object involves some study, allowing your brain & eye collaboration to bring out the more subtle features of the field. But even given that, M97 remains an averted vision only object, impossible for me to honestly comment on size or form given its tenuous nature.

Out of curiosity I decide to push things a little and add a 2x Barlow into the optical path. A quick refocus on Dubhe and I'm off to the Owl again. This time I am able to see the glow a bit more readily, enough that I can judge that it is more or less round in shape. It's still an averted vision only object, but the higher magnification seems to darken the background a bit and make the planetary slightly easier to see. 

The Owl had been a challenging target, possibly at the limit of what I can do in terms of this equipment and location. I saw yet again that surface brightness does not provide an infallible predictor of whether an object can be seen, only an estimate (something I plan to explore in part II). But without question this observing session served to reinforce some of the best practices when trying to pluck a DSO from skies bathed in city lights:

• Guard your dark adaptation, even if your neighbors may think you're a bit weird sitting in your driveway with a pillow case over your head.
  
  
• Averted vision should be applied thoroughly and systematically when inspecting the field.
  
  
• Just as a camouflaged animal gives itself away when moving, inducing a little movement in the field can sometimes unveil a faint target.
  
  
• Contrast is crucial. To that end a light pollution filter (UHC, OIII) can improve the view if the target is an emission nebula and bright enough to overcome the light loss caused by the filter. Boosting the magnification is another way to enhance the contrast and will work regardless of object.
  
  
• Patience - above all, patience! Study the entire field carefully, giving each section a few moments of attention and then review them again. While our eyes don't build up an image over time like a CCD, your eye & brain do collaborate to gradually reveal dimmer objects as you spend time at the eyepiece.

 

Got to GoTo?

So if I yelled "Tastes Great!...Less Filling!" - what comes to mind? If you grew up in the 80's (and maybe even if you didn't) you'll recognize that as the catch phrase for Miller Light beer, ranked as one of the most successful marketing campaigns of that era. It epitomizes the situation of two camps staking out and digging in around their assessment of a product. 

Amateur astronomy has certainly seen its share of hotly debated issues. For many years as digital photography came to the marketplace we sparred over whether it would (or even could) replace film for capturing quality images of deep sky targets. That one seems to be settled. Then there is the occasional discussion of whether digital media is better than a hard copy. I'll confess that I still like a book/magazine/newspaper in its printed format over the digital. There is something thoroughly enjoyable about thumbing through a volume of Burnham's Celestial Handbook, perusing a constellation that will be available for viewing that night. But as the digital revolution has unfolded we also enjoy the portability and accessibility of online content.

One enduring topic of debate is most certainly the merits of using a computerized mount with "GoTo" capability when you are out under the stars. For the better part of 50 years I've been a star hopping guy, planning my trip to that evening's targets with a little research and printed maps to outline the approach to be used. Sometimes half the fun was that research and planning to capture the target, and then successfully bagging that faint fuzzy provided a sense of achievement and affirmation of my skills. Undoubtedly it gave me a foundation of the heavens and the ability to bring a variety of celestial showpieces into the eyepiece on any given evening without any aids.

As I've noted in prior postings, last August I invested in a Celestron CGX-L mount. My main motivation was the hope of better tracking for some photography and the ability for it to bear a larger OTA than my old Orion Atlas mount could handle. One of the features of the mount is, of course, "GoTo" functionality. I will confess that it's very seductive. 

My current project has been revisiting the AL Urban List objects using my 80mm Vixen refractor. The open clusters in Monoceros are particularly challenging since there are very few stellar guideposts available amid Bortle 8 skies to serve as a foothold when setting out on the star hop. So when taking the scope out this past week on a cold and clear winter evening my prep was primarily generating a list of objects along with a very brief description. Once aligned the mount did a fantastic job of centering the targets, leaving me time to inspect and sketch each of them. Where I might have bagged one, possibly two, of these clusters by star hopping I was instead treated to a very pleasant and productive session before my toes became too numb.

I would submit that there are strong parallels between "GoTo" functionality and our reliance on satellite navigation when driving to an unknown destination. It's said that many under the age of 25 simply have no skills for picking up a map and using it to see where they are and how to get where they need to go. While I do make use of apps like Wase from my phone, especially in heavy traffic or when driving solo to someplace I've not been to before, I often will not bother if the route is one I'm reasonably familiar with. As a teenager delivering prescriptions for my dad's pharmacy in Baltimore I acquired a pretty good sense of the main arteries and thoroughfares around here, so it seems natural to eschew the voice giving me commands and go my own way. It may be that getting your terrestrial bearings and navigating from a map is going to be relegated to a sort of black art practiced by old codgers like myself. I am still amazed sometimes how the person behind the counter is totally reliant on the cash register to determine the change due from a $7.23 meal when I hand them a $10 bill. Thanks dad, having me work at the pharmacy taught me that one as well.

But back to our task of celestial navigation. There is another value to star hopping beyond getting a grasp of the sky. As noted by Bob Prokop in a recent thread on the HAL group, you have no idea what little gems you are gliding past when in autopilot mode. I specifically recall stumbling across the beautiful double star WZ Cassiopeia one night on my way to NGC 7790. I likely spent more time looking at that then the intended target.

Perhaps the appropriate balance for a new telescope owner with the technology is to challenge themselves to star hop to the brighter Messier and Herschel 400 objects. It is not that hard and gives you the satisfaction of bagging the target based on your skills, not your equipment's. Take your time when sweeping the area for your quarry and soak in the neighborhood, letting your eye search for colors and your brain form interesting patterns among the field of stars. Simply because it does not get called out on an atlas doesn't mean it's unworthy of a few moments of admiration. But then when the need arises to find (or confirm) the end point of a challenging star hop, you'll find that computer assistance to be a real boon. Yes, computerized mounts can be highly efficient, but is that really where the enjoyment lies in amateur astronomy for you?