For our northern targets we will visit the prominent constellation of Cygnus for a couple of very diverse objects, plus stop by the diminutive Delphinus for another. In the south we will visit Indus, Capricornus and Aquarius. I encourage everyone to make room in their observing, sketching and/or imaging plans to visit as many of these objects as you have access to from your specific location. Plus, I hope you will report back to this forum your results with these objects so everyone can share in your enjoyment and learn from your experiences.
So with that, let’s get going, and let me present the
Northern Celestial Hemisphere
This bright cluster is found in eastern Cygnus just over 9° ENE of Deneb. It was first recorded by Aristotle in 325 B.C., but Charles
We now head into one of the smaller constellations (69th out of 88 in terms of area) in the sky, Delphinus the dolphin. Easily recognizable by its kite-like appearance it contains no
Veil nebula (Cygnus, supernova remnant, mag=7.0, size=3.0°, SBr=18.0):
The famous Veil Nebula is without a doubt one of the most intriguing and beautiful objects in the northern sky. It is the visible portion of the larger Cygnus Loop (catalogued as SNR G074.0-08.6 or Sharpless 103), which is the result of a supernova explosion over 10,000 years ago, the progenitor of which was over 20 times the mass of our own sun. It lay at a distance of approximately 2,400 light years. Its field is about 2.5° south of mag 2.5 Epsilon Cygni (Gienah). At about 3° in diameter its field is expansive.
In areas with significant light pollution it can be an extremely challenging object to detect visually, escaping detection. It is highly responsive to O-III line filters and to a slightly lesser degree with a narrow-band nebula filter. As light pollution becomes less an issue, it becomes more readily apparent. While it can be seen without a filter in darker skies, it truly comes into its own with the use of one. Because of its low surface brightness, the use of a filter boosts its contrast against the sky rendering a much larger portion of its intricate structure visible.
Typically this complex is viewed as having three main portions, the eastern, western, and central which consists of a triangular shaped section called Pickering’s Triangle or Wedge (Simeis 3-188). There are a total of six portions of the complex that appear in the
https://skyandtelescope.org/astronomy-b ... il-nebula/
Southern Celestial Hemisphere
ESO 236-7 (Indus, open cluster, mag=7.0, size=30.0’, class=II3):
This open cluster is found in the European Southern Observatory Catalogue. The object is located just over 1.5° north of mag 4.4 Theta Indi. First plotted by Petrus Plancius the constellation Indus represents the “Indian”, though which indigenous group it supposedly represents is unknown. Visually the cluster is not particularly rich or overly detached from the stellar field. It is dominated by eight star ranging from 6th to 9th magnitude that straggle SSE to NNW, with several more of 10th and 11th magnitude dotting the field around the main grouping. Though not an outstanding visual treat, it still is a curious little grouping in a dimmer constellation known more for its galaxies. To aid you in locating this cluster, its J2000 position is: R.A. 21h21m28.0s,
We now travel to the celestial sea goat. Though the name Capricornus is Latin for "horned goat" or "goat horn" or "having horns like a goat's", it is typically referred to as a “sea goat” – half goat/half fish. Regardless, it is an obvious constellation in the southern sky, with its primary stars forming a very large triangular pattern to the east of Sagittarius. Though the constellation is home to many galaxies, it is best known in the
It is easily observed from a goodly portion of the northern hemisphere as well, and presents a modestly large round glow with a tight core. It can often be picked up in a standard 8x50
Our final object for this edition of the challenge is a very popular and famous planetary nebula in the water bearer constellation. Though Aquarius is a large and relatively dim constellation, overall it does contain a few brighter stars, and certainly is home to a plethora of
The nebula displays an annular structure, but unevenly so as some portions appear brighter than others. Particularly the western edge of the ring structure may seem dimmer as compared to the remainder. The magnitude 13.5 central star is fairly easily seen, and with larger
This object has a bit of a checkered discovery history. The first “discovery” was by Karl Ludwig Harding in the 1823-24 time frame, ironically utilizing an 8.5 inch reflector built by William Herschel that was housed at the Gottingen University Observatory. He is given credit though no fewer than three other independent discoveries were reported because of the lack of knowledge of those previous discoveries. Though the object was included by John Herschel in his General Catalogue, it was never observed by him or his father William Herschel. This was quite likely because of its large size and resulting lower surface brightness.
With that, I will turn this little project over to you. Whether you are a visual observe like myself, someone who enjoys sketching at the eyepiece, or prefer the imaging side of our hobby, there should be something here for you. Be sure to let us know here how your endeavors turn out. Sharing our common experiences in the field is the most productive way for us to learn from one another. Keep looking up there friends cause that's where the good stuff is!