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Some Light Science Reading. The Constellations: Lyra

Saturday, August 4th, 2012

As first appeared in the July 2012 edition of the Syracuse Astronomical Society newsletter The Astronomical Chronicle.


Image generated with Starry Night Pro 6.

“The muse is upon me… bring me a small lyre!” – Caesar (via Dom DeLuise)

I have come to the conclusion that the constellation Lyra is my favorite, as it has all of the qualities one looks for in a celestial marker for a student of astronomy history, an amateur astronomer, and a part-time musician (well, drummer). Within its defined borders reside a famed double-double star system, a planetary nebula, a small globular cluster, at least one reasonable galaxy, one of the brightest stars in our night sky, a near-perfect parallelogram (if these were brighter stars, they would rival the Belt of Orion in geometric significance to terrestrial observers), one corner of the largest asterism in the night sky (the so-named Summer Triangle), and a host of other stars and dimmer objects (including even a few comets right now). This great variety of objects all lie in a small piece of property just off the band of the Milky Way and, during the summer, they are all ideally suited to near-zenith or at-zenith observing.

For our overture, we begin with the history of this mythic instrument. Lyra has most oft been associated with the famed musician of olde Orpheus, where Orpheus’ lyre was disposed of in a river not long after Orpheus himself was disposed of by maenads despite Orpheus giving the performance of his life (or for his life as the case may have been, as his playing reportedly kept rocks and sticks at distance, requiring the maenads to forego accouterments and pluck Orpheus apart with their own hands). Zeus, with his ever-present eye for collector’s items, ordered the lyre placed in the heavens along with the eagle that recovered it (and some old drawings of the constellation still include a bird of some kind in the rendering).

The show continues with the frame of the lyre itself, rendered in the opening image as a parallelogram topped by a “T.” When I see the constellation, I don’t see the “T” as much as I see an additional triangle composed of Vega, ζ1 Lyr (a double-star that connects the triangle to the parallelogram), and ε1a/ε2a Lyr (far left of the image above, connected by the red line). Now then, ε1a/ε2a Lyr is a sight to behold in a telescope, as it is not one star, but instead a pair of binaries, meaning four stars total that resolve nicely under reasonable magnification (it is reported that, under ideal conditions, the two pairs themselves can be split naked eye). This famed “double-double” star is shown below in an image from the Harrison Telescopes website.

Vega is the fifth brightest star in the Night Sky (making it the sixth brightest star in our sky) and is the second star to appear during the summer months after Arcturus. During June and July, Vega first appears high in the North-Eastern Sky and is obvious to anyone waiting at Darling Hill for their eyes to adjust after sunset. This makes Vega an easy marker for anyone learning the Summer constellations, which then makes Lyra an easy constellation to get under one’s belt at the same time. The parallelogram (where one might imagine the plucked strings of the lyre to be) is oriented nearly North-South and runs along the neck of Cygnus the Swan, a Constellation embedded well into the river of stars that make up the Milky Way.

With the constellation of Lyra identified from its two prominent geometric themes, the search for the subtle tones in this constellation can continue. After M13 in Hercules and the famous M31, the object I learned to identify from the relative positions of stars was M57, the Ring Nebula. M57 sits like a tuning knob at the base of Lyra, almost centrally located between the binary star Sheliak and Sulafat. While far from the brightest object in the night sky, the Ring jumps out immediately even under low-power binoculars as something clearly not a pinpoint of light. New scope owners looking to find anything(!) in their scope are well-advised to consider M57 as a target for low-magnification observing, as the appearance of Sheliak and Sulafat in an eyepiece help to set bright boundary conditions between which to scan for the nebulous ring. On ideally clear and steady nights, the central star of the Ring is visible, although this can be a heroic undertaking for even seasoned pros. A comparison of what Hubble sees and what you’ll likely see is provided on the previous page.

Containing the Ring Nebula would be enough for any constellation to be noteworthy to an amateur astronomer, but Lyra is famous as being a host to yet another Messier object in the form of M56, captured above-right by Stu Forster in July of 2010. This small globular cluster has been tagged at 13.7 billion years of age and can be found most easily by drawing a straight line between Sulafat and Alberio (the head of Cygnus the swan) and scanning the midpoint with larger-aperture binoculars or a small telescope.

For those listening most intently to the orchestrations of this constellation, the irregular galaxy NGC 6745 is just visible in medium-sized telescopes (shown above from Hubble). NGC 6745 is decidedly less J. S. Bach and decidedly more John Cage, as 6745 is actually three galaxies in the process of a violent dance. Like a famous Big Band moving through a town of jazz combos, the largest galaxy is pulling stars from the two smaller galaxies, populating itself at the expense of the disrupted musicians.

There are even themes implied but not heard that enhance the complexities of Lyra. To date, over 13 exoplanets have been discovered in Lyra, at least three of which are attributed to the position of the Kepler Mission observing envelop just beyond Cygnus (see the image above, which shows Kepler frames just to the edge of Lyra).

- Happy Hunting, Damian

Some Light Science Reading. The Constellations: Camelopardalis

Wednesday, August 1st, 2012

As first appeared in the June 2012 edition of the Syracuse Astronomical Society newsletter The Astronomical Chronicle.


Image generated with Starry Night Pro 6.

We continue our presentation of CNY circumpolar constellations with a relative newcomer to the great list of 88 constellations (in Western Culture, anyway). Camelopardalis the Giraffe is lucky to be identified as a constellation at all, as neither the Greeks nor the Romans saw this part of the sky as interesting enough to, dare I say, stick their necks out and define the stars here as anything of importance. Its Western history dates to approximately 1612, when the famed Dutch astronomer and cartographer Petrus Plancius (who also provided us with Monoceros, another recent constellation in the Northern Hemisphere) grouped the stars with the name Camelopardalis which, loosely translated, breaks down into “camel” and “leopard,” the combinations of “long neck” and “spots” being a reasonable first approximation to the features of an animal most of Europe had likely never seen at the time. The Chinese and Indian astronomers, on the other hand, were far more meticulous in their use and definition of stars in the Night Sky and the brighter stars in Camelopardalis are all defined in one asterism or another. The positions are obviously the same, but the history and mythology of the stars in Camelopardalis are markedly different.

Referring back to the main image in my first article on circumpolar constellations (Ursa Minor, Jan/Feb/Mar 2012, above), that vast majority of Camelopardalis lies above the Northern Horizon, with its head region tightly packed between the boundaries of Draco and Ursa Minor. I’ve seen several stick figure representations of Camelopardalis that attempt to depict only the legs (from the brightest stars in the constellation), only the legs and torso (by cutting Camelopardalis off at the knees and connecting these two starts to make a body), only the legs and half the neck (using bright stars again), the legs and full neck (getting a head in there as well), and the full-on head-neck-torso-short-leg variation that looks most like a giraffe but, likely, deviates most from classical definitions. The correct line drawing for you is, of course, the one that helps you identify the constellation easiest.

During the June mid-evenings, Camelopardalis is oriented with its feet standing firmly on the Northern Horizon (perhaps with its legs obscured behind tall trees that serve as celestial underbrush during our observing sessions). With no star brighter than 4th magnitude and most in the 4th to 5th range, one does have to work a bit harder than usual to mark out the legs and torso of Camelopardalis from Darling Hill, as the electromagnetic diaspora emanating from Syracuse consumes an ever-increasing expanse of the Northern Sky (a solution, then, is to simply observe from somewhere comfortably North of Syracuse!). As you check for the neck, consider the head of Camelopardalis reaching for the bowl of the Big Dipper. The brightest star near where the head would be, the appropriately named “HIP47193,” will sit just to the left of Polaris for your early-night June observing.

Neither the Greeks, nor the Romans, nor most any Western Culture, nor Charles Messier or his assistant Pierre Méchain found anything of importance to amateur astronomers among the stars we know as Camelopardalis. It took until the 18th century for William Herschel to identify an object worthy of cataloguing in the forms of the sort-of elliptical/sort-of spiral galaxy NGC 2403 (shown above, from Hubble). We now know that this region of the sky contains many interesting, but faint, observables, some of which lie within the Milky Way (such as the planetary nebula NGC 1501 and the open cluster NGC 1502) and many which lie far, far beyond, all likely visible only because they lie away from the galactic plane of the Milky Way (and, therefore, are identifiable because they are in a relatively barren stellar savannah that doesn’t obscure our view). Among these are NGC 2655, IC 342 (shown below in infrared from NASA WISE), and NGC 1569 (all exceptionally tough targets due to Syracuse light pollution).

- Happy Hunting, Damian

Some Light Science Reading. The Constellations: Orion

Friday, April 27th, 2012

As first appeared in the April 2012 edition of the Syracuse Astronomical Society newsletter The Astronomical Chronicle (PDF).

Image generated with Starry Night Pro 6.

Much can be said about the old hunter Orion. To Central New York observers, it had (until very recently) been the case that Orion made his way across the Night Sky during the coldest and least hospitable (to most nighttime observers) months of the year. Conditions would keep observers in hiding from him (some of the best CNY observers I know would risk surgical strikes on the Orion Nebula with their fastest to set-up and tear-down equipment). The abbreviated winter of 2011/2012 and reasonably early start of the SAS observing season have provided us with excellent opportunities in the past few months to make Orion The Hunter now the hunted. The mid-April observing session will be the last “official” opportunity to observe Orion before he disappears behind the Western horizon until the most nocturnal of us can next see him in our Eastern sky before sunrise in late August. I then take this opportunity to discuss Orion, one many CNY/SAS members may know the best by sight but may know the least by observing attention.

One of the topics covered in the 2011 SAS lecturing series was how we observe. Not the discussion of optics or the physics of planetary motion along the ecliptic, but the visual and mental mechanisms we use to translate the photonic triggers in our retina into mental pictures of celestial objects. Orion was the astronomical example I used to describe Pareidolia, how we impose a kind of order on things we see despite that order not being present in the actual collection. When you look at a cloud, you may see a face, an animal, or something your mind triggers as being something it clearly is not. I often placed the infamous “Face On Mars” next to the Constellation Orion to show clearly how we see what we think we see despite all reasonable evidence to the contrary (or the two can be mangled together, as shown below). The clouds may look like an animal, the “Face On Mars” looks unmistakably like a shadowed face, and Orion, as it happens, has looked like a human figure to virtually all peoples for as long as we have record of Constellations, the same way Scorpius has appeared as a scorpion to every civilization for which this little monster was part of the local biosphere.

Pareidolia is not just for cognitive neuroscience! One of the keys to learning the sky I discussed last year was to let your mind wander while staring at the sky and see if certain things jump out at you. The constellations are, for the most part, made up of the most reasonably bright star groupings, but if you see any type of geometry that makes some part of the sky easy to identify, run with it. This same philosophy may be responsible for the rise of the asterism, or “non-Constellation star grouping,” as the distillation of mythological complexity into more practical tools for everyday living. For instance, I suspect everyone reading this can find the asterism known as the Big Dipper, but how many know all of the stars of its proper Constellation Ursa Major? Our southern tree line and Cortland obscure some of the grandeur of Sagittarius, which means we at the hill identify the location of its core (and several galactic highlights) by the easy-to-see “teapot.” The body of Orion is a similar case of reduction-to-apparent, as the four stars marking his corners (clockwise from upper left)…

Betelgeuse (pronounced “Betelgeuse Betelgeuse Betelgeuse!” – marking his right shoulder; a red supergiant of very orange-ish color even without binoculars)

Bellatrix – the left shoulder (so you now know the Constellation is facing us as originally defined) – a blue giant known also known as the “Amazon Star”

Rigel – the left foot; a blue supergiant and the star system within which the aliens that make the Rigel Quick Finder reside

Saiph – the right foot; a star dim in the visible but markedly brighter in the ultraviolet. Saiph and Rigel are about the same distance away (Saiph 50 light years closer at 724 light years, a point to consider as you observe them both)

… and the three stars marking his belt (from left)…

Alnitak – A triple-star system 800 light years away with a blue supergiant as its anchor star

Alnilam – the farthest star of the belt at 1359 light years, this young blue supergiant burns as brightly as the other two, making the belt appear equally bright “al across”

Mintaka – 900 light years away, this is an eclipsing binary star system, meaning one star passes between us and the main star in its orbit (about every 5.7 days)

… are obvious to all, while the head and club stars require a longer look to identify.

Sticking to Naked Eye observing for a moment, Orion is not only famous for its historical significance and apparent brightness. Orion is ideally oriented to serve as an order of alignment for several nearby Constellations and is surrounded by enough bright stars and significant Constellations that curiosity alone should have you familiar with this part of the sky in very short order. As an April focus, it is of benefit that all of the Constellations we’ll focus on either hit the horizon at the same time as Orion or they rest above him.

I’ve color-coded the significant stars marking notable Constellations in the image below. If you’re standing outside on any clear night, the marked stars should all be quite obvious (we’re talking a hands’ width or two at arm’s length). From right and working our way counterclockwise…

(RED) Following the belt stars to the right will lead you to the orange-ish star Aldebaran, marking the eye of Taurus the Bull. This is a dense part of the sky, as Aldebaran marks both the head of the Bull and also marks the brightest star in the Hyades star cluster (a gravitationally-bound open cluster 150 light years away composed of over 100 stars). Just to the right of this cluster is the “Tiny Dipper” known as the Pleiades (Messier 45), another dense star cluster worth observing at all magnifications. Both of these clusters are simultaneously easier and harder to find at present, as Venus (“1″) is resting just above them, providing an easy way to find both clusters but plenty of reflected light to dull the brilliance of the two open clusters.

(ORANGE) Auriga, featuring Capella (the third brightest star in the Night Sky), is an oddly-shaped hexagon featuring a small triangle at one corner. Auriga, like Ursa Minor in last month’s discussion, is made easy to find by the fact that the five marked stars are in an otherwise nondescript part of the sky (relatively dim generally, but brighter than anything in the vicinity). Venus will dull Hassaleh (Auriga’s closest star to Venus and the two open clusters below it) but Elnath and Capella will be easy finds.

(YELLOW) Castor and Pollux, the twins of Gemini, are literally standing on Orion’s club. Making an arrow from Mintaka (the right-most star of the belt) and Betelgeuse will lead you to Alhena (Pollux’s left foot), after which a slow curve in a horseshoe shape will give you the remaining stars.

(GREEN) Canis Minor is two stars (which is boring), but is significant for containing Procyon, the 7th brightest star in the Night Sky (which means it will be an EASY find). But don’t confuse it with Sirius, which is the big shimmering star in…

(BLUE) Canis Major is the larger of Orion’s two dogs and contains Sirius (“The Dog Star”), a star so bright (magnitude −1.46) and so close (8.6 light years) that it appears not as a star but as a shimmering light. Some would say an airplane, others would say a hovering UFO. Part of my duties as president involve intermittently explaining that it is not the latter.

And, with respect, Monoceros is an old Constellation but not a particularly brilliant one. Having Canis Minor and Canis Major identified will make your identification of Monoceros quite straightforward.

We now turn to the other “stellar” objects in Orion, composed of three Messiers and one famous IC. M78 is a diffuse nebula almost one belt width above and perpendicular to Alnitak. You will know it when you see it. M43 and M42 (marked as “4″ in the image below), on the other hand, are so bright and close that you can see their nebulosity in dark skies without aid of any optics.

M42 – The Orion Nebula is, in the right dark conditions, a Naked Eye sight in itself. For those of us between cities, even low-power binoculars bring out the wispy edges and cloudy core of this nebula. For higher-power observers, the resolving of Trapezium at M42′s core serves as one of your best tests of astronomy binoculars (I consider the identification of four stars as THE proper test of a pair of 25×100′s. Ideal conditions and a larger aperture will get you six stars total). You could spend all night just exploring the edges and depths of this nebula. You can take a look back at the Astro Bob article in the April 2012 edition of the Astronomical Chronicle (From My Driveway To Orion, Nature Works Wonders) for a more detailed discussion of this part of Orion.

M43 – de Mairan’s Nebula is, truth be told, a lucky designation. M43 is, in fact, part of the M42 nebula that is itself a small part of the Orion Molecular Cloud Complex (not THAT’S a label). M43 owes its differentiation to a dark lane of dust that breaks M43 and M42, just as the lane of dust in our own Milky Way we know as the “Great Rift” splits what would otherwise be one continuous band of distant stars the same way a large rock in a stream causes the water to split in two and recombine on the other side.

Finally (and the one you’ll work for), IC 434, the Horsehead Nebula, lies just to the lower-left of Alnitak (1). The Horsehead is itself a dark nebula, a region absorbing light to make it pronounced by its difference from the lighter regions around it. To put the whole area into perspective, The Horsehead is itself STILL within the Orion Molecular Cloud Complex. The sheath of Orion’s Sword and nearly the entire belt is contained in this Complex, like dust being rattled off with each blow from Orion’s club.

I close by taking a look at the perilously ignored club attempting to tear into Taurus. At present, asteroids surround Orion’s Club like pieces of debris flying off after a hard impact. All are in the vicinity of 12th magnitude (so require a decent-sized mirror), and all are also moving at a sufficiently fast clip that their paths can be seen to change over several observing sessions (if, by miracle, enough clear days in a row can be had to make these measurements). I have highlighted the five prominent ones in the image below.

Is it an oddity to have Orion so full of asteroids? Certainly not! Orion is placed near the ecliptic, the apparent path of the planets in their motion around the Sun. Orion’s club just barely grazes the ecliptic at the Gemini/Taurus border, two of the 12 Constellations of the Zodiac, the collection of Constellations that themselves mark the ecliptic. As nearly all of the objects in the Solar System lie near or within the disc of the Solar System, you expect to find all manner of smaller objects in the vicinity of the Zodiacal Constellations. In effect, Orion’s club is kicking up different dust all year long as the asteroids orbit the Sun. You only have a few more weeks to watch the action happen before Orion’s return in the very early early morning of the very late summer.

- Happy Hunting, Damian

Some Light Science Reading. The Constellations: Triangulum

Thursday, October 7th, 2010

As first appeared in the October 2010 edition of the Syracuse Astronomical Society newsletter The Astronomical Chronicle (PDF).

Constellation Map generated with Starry Night Pro 6.

I remember my first foray into Constellation memorization, still the first thing I recommend for anyone beginning in amateur astronomy (primarily for using these imagined creations to memorize the locations of far dimmer objects when you graduate up to binoculars or small scopes, but also simply to develop a sense of, well, the space between these creations as you jump between objects).

Orion, yeah yeah… Scorpius, O.K. obvious… The body of Sagittarius looks like a teapot, that’s not bad… Cassiopeia is the great big “W” Jonathan Winters discovered in “It’s a Mad … Mad World“… The “Dippers” are dippers… Canis Minor is composed of two stars, and they happen to be in a straight line! At least it contains a bit of animal lore and the great Procyon. That should be easy to find.

Ah! Triangulum. A famed triangle of stars. Named after the famed shape called “The Triangle,” and believed to be the last Constellation drawn out by Ptolemy as one of the original 48 Constellations of Antiquity. It bet it was supposed to be “The Great Northern Spearhead,” but Ptolemy must have been a pacifist. It is believed he committed it to papyrus at 4:50 p.m. on a Friday before the scribes began copying the first edition Monday morning.

I have to admit, this Constellation seemed like an odd member of the original series, if for no other reason than the seemingly minimal amount of work (or so I thought) that must have gone into its creation. As I hope to convey to you in the next few paragraphs, this little Constellation has stood the test of time for a few good reasons.

To begin, the heart of Triangulum dates back all the way to the Babylonians (which means it likely also dates back further into pre-recorded history) who, with the inclusion of what we now know as γ-Andromeda, called this Constellation MUL.APIN, or “The Plough.” With this simple extension added in red in the image above, I hope the resemblance is now obvious. To my technologically-biased mind, the nondescript triangle of the modern sky instantaneously becomes the (seemingly) everlasting testament to the power of agriculture and the shining reminder to all of the simple tool responsible for the creation of a commodity we know today as “surplus.” I don’t think that’s going too overboard in the description.

You are here.

We have these “organic farming” discussions where people ask you “Where do you think your food comes from?” It has been quite a recent phenomenon in the long history of this little sphere Carl Sagan referred to as a “Pale Blue Dot” (that’s you at right) that the members of a society have been relieved of the strain of producing for themselves by technology that improves efficiency and, more importantly, vastly increases quantity. If I take the comparison to the extreme, the Constellations that represented tools or deities have been replaced in many societies by the gigantic billboards that celebrate the financial well-being of companies continuing their crusade to relieve you of your currency, an economic reality impossible in a society where everyone’s working entirely to maintain a base subsistence level. The world remains in transition towards a time when all are at the same technological level as the First World countries (and it is only a matter of time), meaning something as simple to many of you reading this as an animal-driven plough remains a vital key to survival in other parts of the world.

I vote we re-designate the “Summer Triangle” as the “Summer Plough!”

While it may have been a signal for a Late-Summer party at the very beginning of some harvest, the Babylonians used the presence of their Triangulum to mark the “Way of Enlil,” the apparent path of the Sun after the Summer Solstice. In a society that used the Heavens as their Calendar, this simple Constellation took on a wholly more significant meaning.

Thanks to wikipedia, I know that a more recent attribution (to only the Triangle, not the Plough) of this Constellation is to the goddess Ceres, who successfully convinced the god Jupiter to add the island of Sicily (at left, the football that the boot of Italy appears to be kicking towards the U.S.) to the Night Sky (perhaps a preferred way to leave your mark in history, esp. given the alternative taken by Atlantis).

Sicily, featuring an active Mount Etna (Image by Jacques Descloitres, NASA MODIS Land Rapid Response Team).

Given this most interesting history, is there anything to actually do with a pair of eyes or an eyepiece in this part of the sky? I’m pleased to report that this part of the sky is actually quite busy (the Star Map at this beginning of this article is about as busy as one can get without looking at Sagittarius), with Triangulum serving as a useful anchor for finding a number of objects in our Eastern sky this month.

M33, the Triangulum Galaxy. Photo by Hunter Wilson.

As it happens, one of the precious few naked eye galaxies (provided ideal viewing conditions) in the Northern Sky lies just to the South (to the right as you’re looking at it) of α-Tri. M33 (at right), appropriately named the “Triangulum Galaxy,” is a member of the Local Group of galaxies (the most famous member being our Milky Way, the second most famous being the Andromeda Galaxy) and, at 2.9 million light years away, lies (by some estimates) 700,000 light years farther from us than the Andromeda Galaxy (M31) AND, according to measurements using the Very Long Baseline Array, is moving at 190 km/second relative to us and towards M31 (the demolition derby will not be pleasant for M33, given it contains only 4% of the stars of M31 (how many mopeds are there in a semi-rig?). It is still under debate as to whether or not M33 is a companion galaxy to the more massive M31 (they do share proximity), but it certainly stands on its own as a spectacle in a good telescope on a dark night. This first recorded observation (it all comes down to paper) is attributed to Giovanni Battista Hodierna around 1650 (above at left), the most famous recorded observation (it all comes down to publication) can be given to Charles Messier (above at right) on August 25-26, 1764 (now that’s bookkeeping!).

Giovanni Battista Hodierna (left) and Charles Messier (right).

All of the other objects in the boundaries of Triangulum are dim (10>th order or dimmer), making your time spent with moderate optics in this area short compared to the time you’d likely spend just on M31 alone. As a good practice for the next Messier Marathon, you can use M33 (*1) and M31 (*2) to mark the Southern side of a rectangle composed of M33, M31, M34 (*3) and M76 (*4, these last two are right on the Perseus-Andromeda border). As M33 will give you M32 and M101, that’s a quick-six to check off as you plough your way through the list of 110.

Comet Hartley 2 and NGC 457 (the E.T. Cluster). Photo by SAS member Stu Forster.

AND, as long as were in this neck of the woods (and the tree line in this part of the sky at Darling Hill is now just becoming more bearable to the impatient observer with the falling of leaves), we can use the Babylonian form of Triangulum to quickly point our way to M76, then slowly walk the Telrad to the North (left) until we reach the Southern Double of the famed Double-Double, which then puts into view both members of the Perseus Double-Double Cluster (NGC 884 and NGC 869) and Comet Hartley 2, which is working its way through our neighborhood. Our own Stu Forster managed to capture Hartley (green glow at left) as it passed through the local neighborhood of NGC 457, more commonly known as the Owl or E.T. Cluster (yes. tha E.T., the two bright eyes work for both).

Clear skies, Damian

Some Light Science Reading. The Constellations: Cygnus

Saturday, July 24th, 2010

As first appeared in the June/July 2010 edition of the Syracuse Astronomical Society newsletter The Astronomical Chronicle (PDF).

Constellation Map generated with Starry Night Pro 6.

Those in the vicinity of Manlius, NY are no doubt aware of the presence of Sno-Top (home of the best soft black raspberry in the area, IMHO) and the duck pond at town center(-ish). Those continuing just a tad further along Fayette Street (92, DeWitt-to-Cazenovia direction) also know that the swan population is localized to the higher pond near the Saucy Swan Restaurant (they do make for loquacious patrons). These facts, combined with the oppressive CNY heat of early July, made the choice of Cygnus the Swan obvious for this month’s constellation. Fittingly, Cygnus is an astronomical feast for naked eye, binocular, and telescope observers alike and, as it is half-way between horizon and zenith in early July in the early evening, it is strategically placed for accessibility with all manner of optics.

Cygnus is surrounded by several dangerous Constellations. The animal Constellations Draco, Velpecula, and Lacerta might enjoy freshly killed what the king Cepheus would otherwise enjoy glazed. The massive Constellation Pegasus is a problem in its own right. Trampled by horse is bad enough on the ground, but to have to avoid trampling by a flying one is another matter altogether. Lyra may be the only reminder to Cygnus of its terrestrial past, having been the instrument of choice for one of Cygnus’ human attributions (that man being Orpheus. See below). For those using only their free pair of 1×7 binoculars (that is, your pair of eyes), the cross that makes up the body and elbows of the wings of Cygnus are most obvious. The bright stars Deneb, Sadr, and Gienah (and the nearby Vega in Lyra, the easiest of the stars in this part of the sky to find starting at sunset) are perhaps most obvious, but the rest of the body is pronounced. As the evening progresses (and on reasonably clear nights), the most striking feature of Cygnus is the river of stars and interstellar dust that is our view of the Milky Way (as if Cygnus is flying above it).

As a collection of prominent stars within the body of the Milky Way, you can guess that the Constellation we know as Cygnus has a long and distinguished history. The Greeks (“Give me a Constellation, any Constellation, and I show you that the history of that Constellation is Greek”) have many swans in their mythology, from Zeus (who fathered Gemini and Helen of Troy disguised as a swan, or so the story goes) to Orpheus (turned into a swan upon his death and placed next to his lyre (Lyra) to characters in Ovid’s Metamorphoses. Cygnus is a member of the “Famed 48,” the 48 original Constellations contained within Ptolemy’s Almagest.

Alberio. From wikipedia.org.

At the head of Cygnus is the star Alberio which, upon inspection with even low-magnification optics, resolves into two stars that make up quite possibly the best color contrast in the northern hemisphere (above, from wikipedia). Alberio A (the orange-ish one), is actually itself a true binary, meaning its two stars are gravitationally bound to one another. It is possible, with scopes larger than 20″ and under excellent conditions, to resolve the two stars, Alberio B (the blue-ish one), is a single star that is not gravitationally bound to Alberio A, making this most famous binary an “optical binary,” one where the two stars look very close but only because of our perspective from Earth. If Cygnus is out, this star always makes its way into the eyepiece of the 16″ scope at Darling Hill. Further, for those who like to get their scopes perfectly focused (especially large binoculars), this combination is an excellent test.

M29. From wikipedia.org.

As is the case with all of the Constellations within the band of the Milky Way, Cygnus is host to several binocular and telescope objects. The two pronounced Messier Objects are M29 and M39, both open clusters. M29 (above, from wikipedia) is famous (to me) for being the one Messier Object that does NOT appear in the index of the Peterson Field Guide To Stars And Planets. Believe me, I have tried several times to find it (just assuming the dark conditions kept me from seeing it. It does appear in the Constellation map, though). This object appears within the binocular field of view of Sadr and is small but worth scanning in dark skies. M39 (below, from seds.org) is similarly nondescript, residing between Deneb and the stars of Lacerta.

M39. from seds.org.

Cygnus becomes quite interesting for its wealth of interesting New General Catalogue (NGC) Objects. The four most prominent objects are the North America Nebula (NGC 7000), the Pelican Nebula (IC 5070), the Veil Nebula (NGC 6960, 6962, 6979, 6992, and 6995), and the Crescent Nebula (NGC 6888). The North America (not American) Nebula (below, with the Pelican Nebula to its right, from wikipedia) is a testament to the only mild imagination of the working observational astronomer. Like many nebulae, details can be pulled out of this object with the use of filters. Depending on the conditions, the best way to confirm this structure exists in your scope is, frankly, to move the scope ever so slightly in the field of view of nearby stars and confirm for yourself that some slightly darkened patch of sky is staying put with respect to the background of stars. This approach, combined with averted vision, is definitely my method of choice for finding the locations of objects I may otherwise miss completely (and we’ve all had the experience of NOT seeing something in a scope that another person can even make detail out of). The very low surface brightness of the nebula makes it an at-least binocular object to observe, but it is noteworthy that this entire North America Nebula is reportedly four times the size of the full Moon. The Pelican Nebula (lower right of the image above) looks more like a Teradactyl to me, but there is some similarity in both (in case you do not see it, the pair of eyes are at upper left (with a bright star in each marking the pupils), the beak extends to the left (and is narrower than a typical pelican), and the body extends to some less structured arrangement down to the lower right).

The North America and Pelican Nebulae, photo by Jason Ware. From wikipedia.org.

The Veil Nebula is a collection of nebulae that make for haunting photos. I am very pleased to have a greyscale image of the Eastern Veil provided by our own Stu Forster (below and in the member gallery). This object is very difficult to observe without an OIII filter, but even an 8″ scope will resolve the detail of this nebula with the filter (it is reported that in excellent sky locations, simply holding this filter to one’s eye will make the Veil Nebula stand out). The Veil Nebula has also been the focus of some considerable Hubble imaging time and a web search for these images is definitely worth one’s time.

The Crescent Nebula. Photo by Stu Forster.

Finally, the Crescent Nebula has also been the focus of some astrophotography time by the good Dr. Forster (below (The Crescent, not Dr. Forster)), appearing to me more like a floating brain than a boring crescent. The Nebula is formed by a Wolf-Rayet star, a type of very hot, massive star with a strong stellar wind. This nebula is actually a double-whammy, as the fast-moving stellar wind from this WR star is colliding with the slower stellar wind from this same star when it was a red giant some 400,000 years earlier.

The Crescent Nebula. Photo by Stu Forster.

Clear skies, Damian

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