Regal Gems

One of the best aspects of amateur astronomy is the rhythm of the seasons as reflected in the night sky. As we move deeper into fall we have the return of the familiar "W" asterism in the northern sky - Queen Cassiopeia. The constellations that we bid goodbye to in spring now return. It’s like visiting a familiar vacation spot - we want to see those tourist attractions but we also relish a chance for new road trips and opportunities to experience new vistas.

Like any proper monarch our queen is adorned with jewelry – open cluster are littered across the confines of this constellation. We often think of the northern terminus of the Milky Way to coincide with Cygnus, but that perspective arises from residing in the east coast light corridor. Even when we slip away to darker skies it is rare to get a good appreciation of the winter Milky Way as it flows through Cassiopeia and Auriga. I recall many years ago my friends Bill and Doris Burbridge had a place in western Maryland that they observed from. They invited several of us up one October evening for some observing. Perhaps it was just a night of wonderful transparency coupled with minimal light pollution but the sky was stunning. You readily saw the winter Milky Way, and clusters that I had to tease out from Towson were screaming their presence. Evenings like those constitute an astro-high that we photon junkies of the universe constantly want to recreate!

Setting up in my driveway I am confronted by the realities of suburban living as I strain to see Kappa, the faintest of the six stars that outline the queen’s seat in the heavens. I align the mount and set my 80mm Vixen upon it. First stop this evening is a visit to my friend the Owl, a.k.a. NGC 457. This fun cluster is bright, an easy star hop, and has more than enough stars in it to be readily recognized as an open cluster. The two brightest stars form the eyes of the wise bird, and the fainter members to the northwest constitute body and outstretched wings.

NGC 457

The avian eyes, Phi¹ and Phi² are not only beautiful but amazing suns. Phi¹ is actually a yellow supergiant (bordering on hypergiant) that is some 65 times larger than our Sol and, according to Hipparcos data, an absolute magnitude of -7.8! Think about that for a moment – that value represents an object 40x brighter than how Venus appears to us. For comparison Sol has an absolute magnitude of 4.8, so in a sky where all stars are placed at the same distance from the observer, Phi¹ is an incredible beacon that’d be easy to see in our daytime sky, while our Sun would be lost in the light pollution from most of our region. That’s one heck of a star! The companion star (not a true double) is a blue supergiant checking in at some 83,000 times more luminous than our Sun. So together the Owl’s gaze represents stellar furnaces of a scale that we humans find hard to truly appreciate.
I admire the cluster at 30x, a beautiful object set amid a wonderful star field. I think I can see a slight yellow cast to Phi¹ but it may be my imagination. There are probably close to two dozen cluster members that make up our feathered friend in my eyepiece. I have my camera prepped and ready to go so I take the time to grab several 25 sec shots that can be my indoor entertainment on a cloudy night as I process them.

The next item I want to attempt is NGC 7790, an open cluster NW of Beta Cassiopeiae that I saw years ago working the Herschel 400 list using my 6” reflector. As I recall it was small but pleasantly rich. I’m just not sure I can snare it from this location with my 80mm refractor but it seems worth a try. As I am panning the area in my quest I see another old friend pass through the field. This queen of ours has placed two gems – a sapphire and a ruby – together in her collection of double stars. Known as WZ Cassiopeiae, the primary is a ruddy 7th magnitude carbon star while the companion lying about an arc-minute due east is an 8th magnitude spectral class B (as in blue) star. The relative closeness in magnitudes, the easy separation, but especially the red-blue contrast – all add up to make WZ a fabulous if unsung double star. I linger on it, trying different magnifications to see which eyepiece gives the most aesthetic result. Smaller aperture scopes usually do not have enough light gathering power to do color justice, so I’m really pleasantly surprised how well WZ holds up under a smaller instrument. I decide to swap in the camera again to grab a few shots of my colorful friend.

WZ Cas

Back to my search for NGC 7790. I pan the region, critically examining each field for hints of a cluster. Finally I notice something – a small patch that is exhibiting that ultimate tease of barely showing some stars with averted vision but never robustly enough to allow you to position them in a sketch. This has to be a cluster, likely my quarry. It does have one star that can be seen, perhaps 9-10th magnitude, on the cluster’s trailing edge. The body appears as an ellipse of unresolved nebulosity that is at least partially, if not entirely, based in faint stars just beyond the aperture’s reach. With clusters like these it is easy to understand how over a century ago astronomers were suffering from aperture fever in an effort to prove that all nebulae were collections of unresolved stars. How fortunate for us they were wrong and we instead have a far more interesting universe to explore. I sketch the view of this attractive cluster for later confirmation and then start to break down the equipment due to the hour and my body saying it’d had quite enough cold weather observing for one evening.

In hindsight I wish I had grabbed a shot or two of this one as well, because when I went to confirm it the (ahem!) stars didn’t align. Ok, so what was it then? Well I likely need to revisit and grab a better sketch or a couple images but I’m thinking I landed on next door open cluster NGC 7788. It has the same orientation and, most importantly, that single bright star on its trailing boundary. So that’s my working theory and good excuse to observe again the next opportunity I get.

This serendipitous uncovering of a new (for me) cluster served to highlight how there are often little treasures out there that we pass by either in our haste to get to the main target or simply because we didn’t know to look for something. A few days after my session Richard Orr posted his observation of NGC 436, an open cluster below the feet of the Owl. (Richard also gave a vigorous defense of NGC 457 being a Dragon Fly – but certainly an Owl is a far more regal creature for Queen Cassiopeia!). His posting made me realize I had overlooked it while soaking in NGC 457. It was clearly in view – the picture serves as incriminating evidence of my oversight. So now I have yet another item for my agenda the next clear night – observe NGC 436 with intent!

Snowball Fight

One of my current astronomy projects is to tackle the Astronomical League's Urban List from home using my Vixen 80mm refractor. The program was created about 20 years ago and is designed to suggest a variety of celestial showpieces that should be doable under suburban or even urban venues.

For certain 2018 has been challenging to get out under the stars - near record rainfall and of course the clouds that come with it have given fewer opportunities. Last night my CSC predicted so-so observing conditions but when I stepped outside the skies were pretty crisp and clear - time to get a little observing in!

About a week ago I went in search of NGC 7662 in Andromeda (a.k.a. the "Blue Snowball"). I've picked up this 8th magnitude planetary many times before in both my 6" and 10" reflectors. The biggest challenge is usually the star hop with no nearby stars easily visible, at least where I live. The Great Square of Pegasus is almost always visible, and on most nights I can also pick out Omicron Andromeda (mag 3.6). So the plan of attack was a triangle with the northern side of the Great Square as its base, Omicron my helper to set the height. Looked like a can't fail plan.

Telrad Attack on NGC 7662

Famous last words. I spent well over an hour in search for that little fuzz ball, sweeping at both 30x and 60x over fields where it should be. Made sure I had my "distance glasses" on when sighting the Telrad. Checked the Telrad alignment. Raised the height of the tripod a little to make it easier on my neck. Plenty of pretty pinpricks of light but nary a chubby star that could be my snowball.

I figured I would give it one more go but would change the technique, this time equipping myself with charts that could let me hop to Iota Andromedae and then cascade down the couple of degrees to my planetary, using stars SAO 53202, 53151, and 53039 to pull right up to the Blue Snowball.

It's a great fall evening as I set up the equipment, cool and clear. I can just barely see Kappa with averted vision and glasses on, but I'm able to get it centered. Just as I do I catch a voice from the street "Wow - is that a telescope?" I look up to see a young man - in shorts and a t-shirt as opposed to my scarf and knit hat - checking me out. Well wth, it happens to be "Astronomy Day", right? I call him over and he seems reluctant but then joins me. Hmmm - what to show him? Ah, Saturn is still up, so I pivot the scope 180 degrees for Saturn just before it hits the treeline. With a little coaching he manages to see it at 60x in the eyepiece as he voices his delight. He then mentions that he's seen Saturn before, down at Fells Point, some guy had a scope there. I nod and confirm that it was more than likely Herman Heyn, Baltimore's sidewalk astronomer for many years. I bid him good evening and he meanders up the road. I take a few minutes to admire Saturn myself. Now where was I? Ah yes, trying to get Kappa Andromedae, right.

With Kappa reacquired and at 30x on the scope I have over 2 degrees field of view, so little problem picking up Iota in the same field. But manipulating the scope is cumbersome, as it so often is when getting objects that are coming close to their culmination and in the northern sky. I decide to shift the scope, rotating it east about 60 degrees, sacrificing tracking for easier sweeping. Back again on Kappa I identify to its east SAO 53202 & 53151, which then point me to 53039 (13 And). A little sweep SE and - bingo! Right there, a star that is a little bloated - the Blue Snowball is captured. Let me just grab my sketch book and - oh my, that cop car is stopping and the officer is emerging.

Star hopping down to the Blue Snowball

"Good evening officer," I call out. "Everything OK?"

"Someone called in about a suspicious person in the area. Seen anything?"

I proceed to fill her in about my visitor who might have appeared a bit out of place. I suspect he may be participating in the halfway home farther in town but an easy walk to our neighborhood. I suggest that he is probably just bored and out for an evening stroll and let her know which way he was headed. She hops back in the car and cruises away.

OK, with no tracking the snowball has scurried away from view. But I'm in the area, so in a few minutes it is recentered. Popping in the 2x Barlow to bump the magnificaton to 60x makes it quite obvious that this is a planetary nebula, although it lacks any green-blue color that we sometimes pick up on. It is still small even with the 20mm + 2x Barlow, maybe 10-15" in size, and bright enough to withstand direct vision. No evidence of the progenitor star and no hint of structure - just a fairly homogeneous orb of soft gray light. I swap out eyepieces again for 75x, which the nebula withstands well. No real gain in detail so I think the 60x view wins as one could include 13 And on the edge of the field while keeping NGC 7662 somewhat center stage, making for a nice field star to complement the nebula.

I sketch the view at 60x, noting the stars and approximating the size and intensity of NGC 7662. Just as I wrap up my friend is back, wanting to know if I am seeing anything. I let him know I'm done for the evening but if he sees me out another time he can feel free to ask what's up. "Cool!" he replies. "Well see you later, I think I'm going to go up to Starbucks." And the thought occurs, if I ever want to do some suburban sidewalk astronomy when I retire I bet outside a Starbucks would be a fabulous venue.

Solar System Summer

Every so often it seems the planetary action clumps together. I recall many moons ago when my friend Herman Heyn was doing his sidewalk astronomy gig very routinely that he found a few winters to be challenging to pique citizen interest. Of course being in the heart of light polluted Baltimore made things like the Orion Nebula or Seven Sisters seem a little drab. Compared to Saturn and its rings or Jupiter and its moons, the wow factor just isn't there.

The Family Poses on August 6, 2018

We're approaching that alignment again as Jupiter gradually catches up to Saturn. Two years from now the two superstar ambassadors to amateur astronomy will be huddled together amid the stars of Sagittarius. They'll also be relatively low in the sky for us mid-latitude northern observers, but that won't keep their fans from trying to catch a glimpse of them.

As Labor Day is in our rear view mirror I have to admit that this summer we had a great Solar System family gathering in the evening skies. There was brilliant Venus in the western sky, moving from gibbous to crescent phase all the while maintaining her cloudy veil. Not the best of evening elongations as the western ecliptic lies close to the horizon this time of year, but always a dazzling jewel that is worth visiting and pondering this hellish world - like a scientific experiment gone bad.

Jupiter and GRS in 6" f/8 Reflector July 29, 2018

Next came king Jupiter. This is my favorite planet - not only due to its ample size but especially due to its changing nature. On any given night you might catch a shadow transit on the cloud tops, or the Great Red Spot (which has definitely shrunk but also become a bit ruddier in complexion) staring back at you. Cloud bands with delicate features also await the patient observer or videographer. One evening after having chased down down M104 in my 80mm scope I decided to end with Jupiter to see what the little refractor could do. Cranking up the power with an 8mm TMB Planetary eyepiece + 2x Meade Barlow I was delighted to clearly make out the GRS moving towards the preceding (setting) limb as well as a black pencil point on the clouds betraying Io's presence as it cut across the disk. Old Jove - always the showman.

A couple hours east was full-tilt Saturn, rings wide open as the northern hemisphere has its maximum solar exposure. As he ambles towards Pisces over the next 7 years the rings will gradually fold up until they are razor thin. But for this summer they were in their full glory like a preening peacock - Cassini's division obvious, shadow play on globe and rings creating that wonderful depth of field sensation, tiny moons gathered around the globe. And subtle but evident clouds gradually darkening towards the pole. What's not to love about this view?

Mars on Aug 23, 2018

And finally, bursting onto the stage beyond Saturn was Mars - back with a vengeance from its roughly two year hiatus, sporting a good size disk that we won't see again until (yikes!) 2035. Even with the poorly timed arrival of a global Martian dust storm it still was enticing to see the polar caps and fuzzy albedo markings on the red one. Mars takes magnification well due to its brightness, so you mainly need some patience and steady skies to begin to see some details. Playing around with filters is also enjoyable to see what additional features you might tease out in the different light. While the show's not quite over, for this orb the motto is definitely Carpe Noctum.

A Crowning Achievement

NASA tweeted a link to an article today that takes a look at how scientists fared in predicting in advance how the Sun's corona would appear during the Great American Eclipse this summer using data from NASA resources. The corona (Latin for crown) is the star of the show, the ethereal white light that emerges round an occulted Sun. This super-hot atmosphere of our nearest star is dynamic, being shaped and sculpted by the strong magnetic fields emitted by the Sun.

Scientists used magnetic field information from NASA's Solar Dynamics Observatory to arrive at the prediction. It was far from a trivial model - the "simulation required thousands of processers and took about two days of real time to complete"!

Below was the best guess by Predictive Science, Inc. Below that is my image of the corona, a combined shot using HDR software to bring out the full details. If we rotate the prediction counter-clockwise a bit it really does give a pretty good outline of the shape we saw on August 21st - well done folks!

M13 - Globular Cluster in Hercules

If you say "globular" then odds are 99/100 that the first thing that will pop to mind for an amateur astronomer is Messier 13, a.k.a. the Great Globular Cluster in Hercules. Accessible from spring until fall and riding high in the summer sky it is a grand object. Sir Edmond Halley (of comet fame) was the first to note it as a naked eye object under dark skies. While I think I've seen it without optical aid once or twice it has been an averted vision thing at best.

The least bit of optical assistance, however, does make it quite apparent. One of my fondest memories is seeing it through Charles Cyrus' 10" reflector one evening at a Baltimore Astronomical Society gathering. I had always found hints of resolution in my 6" from Towson, but that evening at the Irvine Center, away from serious light pollution, it burst forth like a jewel, countless stars elbowing each other for attention. It was stunning.

As part of my project of tackling the Urban List with my 80mm Vixen scope from my home, M13 is one of the required stops. It's always an easy star hop (well, provided you don't struggle with locating the keystone) as the two 7th magnitude "sentinel" stars are easy to locate in the spotter scope. And even with such a simple boost to eyesight one can see a fuzzy something between them.

In the scope it's a round puff of smoke, fairly uniform in brightness compared to larger aperture that reveals the steady brightening to a core. With averted vision and higher magnification on a moonless night I can almost swear it just begins to resolve slightly, a few stars dancing just outside of plain view.

For the last several weeks I have been attempting to image the cluster using my Canon t3i and the Vixen scope. The first few attempts gave less than desired outcome. Either the focus was not sharp enough or there were too many shots where there was some trailing of stars due to alignment or camera shutter vibration. But finally this week I managed to acquire about 45 minutes of 30 second images that stacked and produced the photo below. Not bad, it even shows tiny galaxy NGC 6207 (mag 11.5) in the upper left hand side. What amazing technology we have today.

Full Tilt Saturn

Like Earth, Saturn has a tilt to its axis. Ours is 23.5 degrees whereas Saturn is a tad more at 26.7 degrees. The outcome is that as Saturn orbits the Sun we get differing views of the rings. When it is Spring or Fall equinox on Saturn we see the rings edge on. During a solstice they are tilted as fully as possible to us.

Currently Saturn's northern hemisphere is just past solstice and we are enjoying the rings in all their splendor. There is probably no other object in the heavens that is so consistently awe inspiring. While not a large instrument my 6" reflector is more than up to the task of showing some subtle banding on the planet, the gap in the rings (Cassini's division) and some shadow play of the rings upon the planet.

August 9, 2017 at 10:00 p.m. EDT