Some Light Science Reading. The Constellations: Triangulum

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: Pisces

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

Constellation Map generated with Starry Night Pro 6.

Those who've ever been told that "there are more fish in the sea…" should be relieved that we only cast our visual nets to the heavens for stars and galaxies, as this most important of animals throughout history is only represented in the Northern Hemisphere by one pair of gilled swimmers tied at the tails.

The identification of one-half of this constellation as a fish (its other half had originally been a dove) dates back to at least Babylonian times, when a second great Western civilization prospered in the valley of the Tigris and Euphrates rivers to the West of Egypt, home of the first great Western civilization at the Nile Delta. The two civilizations from which most of the astrology (and mythology) that turned into early astronomy was established were founded by key water sources, providing the means for irrigation, transportation, and stable food supplies in the form of fishing, the three key needs of a society that allow for growth and the ability of the few to support the many (as James Burke has considered in Connections and The Day The Universe Changed, the ability of people to NOT need to provide subsistence level support for a society is what promotes scientific growth, cultural evolution, and whatever other types of activities most of us attend to everyday while some small fraction of the U.S. harvests or raises the food that the rest of us consume with hasty abandon). The Greeks eventually solidified the tied-fish representation of Pisces, representing Aphrodite and Eros, tied to one another during their escape from the god Typhon (You can guess how he rolled… In this case, the two were tied so as not to loose one another in the river Euphrates).

This constellation is reasonably large in visual real estate compared to other members of the Zodiac, but is occupied by fairly unremarkable stars, making Pisces one of the less prominent objects in the sky (it is possible you know the location of Pisces by looking below the more pronounced square of Pegasus). Pisces is made pronounced currently by its having caught Jupiter and Uranus at its Southern side, with Jupiter now making its way through Pisces (with a small fraction of time in Cetus) on its way into Aries this time next year. Most all observers will have Jupiter in their scopes at some point this Summer and Fall, giving them a chance to take in a second of the large gas giants in our Solar system as well as one solitary Messier Object within the Pisces boundary while having to move their scopes only slightly.

The only Messier Object within the Pisces boundary is M74, a less-pronounced cousin of the also face-on Whirlpool Galaxy (M51). In Hubble images (below), the bright cloudiness almost shrouds the spiral quality of the galaxy. An infrared image taken with the Spitzer Space Telescope (below) reveals a pronounced web-like quality to this galaxy, as well as some greater definition in the M74 spiral shape.

M74, image from NASA, ESA and the GMOS Commissioning Team.
Infrared image of M74 taken by the Spitzer Space Telescope.

For those attempting to check two planets of their list while memorizing the shape of Pisces, the image below provides you a reasonable cheat-sheet for how to hop from the very prominent (magnitude of -3) Jupiter ("1") to the markedly less prominent (magnitude 5.75) Uranus ("3"). You'll note in the image that the four famous Galilean Satellites of Jupiter (Ganymede, Io, Callisto, and Europa) are virtually on top of one another at this "magnification," giving you an idea of how far the motion will be to find Uranus in your eyepiece. From among the many (invisible) other moons of Jupiter (all of the labels in this image are just a fraction of the total count to date), you'll note a 6th magnitude star at position "2", the brightest other object in the sky in this area. A slow, cautious scope motion to your south-east (and low magnification to start) will help you capture a view of this small blue-ish globe, a fitting color to search for within this aquatic constellation.

Finding Uranus starting at Jupiter. Map generated with Starry Night Pro 6.

Clear skies, Damian