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Constellation Report

Constellation Report

This weekend we move on to the constellation Sagittarius The Archer.

Sagittarius as imaged by Anthony Arrigo of Utah Skies

Sagittarius is pretty easy to find in the southern sky as its brightest stars are prominent. This shot of "the teapot" was taken by Anthony Arrigo of Utah Skies from Park City, Utah. As you can see, the Milky Way is still visible from there :-)

This constellation is typically depicted as a Centaur, a half-man, half-horse creature armed with a bow. I always think of Sagittarius as looking a bit like a teapot. Not seeing many Centaurs these days, the teapot is more fitting for me. Feel free to draw your own analogies.

Deep Sky Report

The focus of our efforts here will be the deep sky objects of Sagittarius. To find Sagittarius, face due south shortly after dark. Sagittarius is due east of Scorpius which we visited last weekend. Feel free to use whatever works for you :) Sagittarius contains probably the most amazing collections of deep sky wonders in all the heavens. It has so many amazing objects, that we'll be forced to limit our selection somewhat. Don't worry... your e-mail box will be busting at the seams when we're done.
For lack of a better idea, we'll simply run the Messier object (all 15 of them) in order. Then we'll move on to the NGC's.
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Ok, let's start things off with a beautiful Diffuse Nebula with a Star Cluster, M8 (mag4.6). Also known as the Lagoon Nebula, this is typically the first object I view in Sagittarius. By sighting from the base star of the teapot's spout up through the two stars at the edge of the spout, you're pointed right in that direction. Also, at mag 4.6, this object is naked eye visible. It is easily visible in binoculars or a small telescope. In a larger aperture instrument, it is absolutely amazing.

Next we'll hit a beautiful Emission Nebula with a Star Cluster, M17(mag6). Also known as the Omega Nebula, this is another awesome treat. Also well within reach of binoculars, this object is further north than our previous object, and therefore easier to view. In a 4-6" telescope, the nebula is clearly visible. In larger apertures... say 12+" awesome detail is visible.

Continuing along we come to a delicate Open Star Cluster, M18(mag6.9). This object is not exactly a "knock your socks off" object, but... it is beautiful nonetheless. Again, binoculars are all you need to view this. Larger telescopes will, of course, reveal many more member stars.

Next up is a nice cluster with nebulosity... or a nebula with a star cluster... your choice. Anyway... it's cataloged as M20(mag6.3). Also known as the Trifid Nebula, this is one amazing object. It is a combination of emission and reflection nebula with some obscuring dust lanes providing nice dividing lines. Again, this object will be visible in binoculars, but... will blow you away in a larger telescope. You MUST checkout this object. This amazing shot was captured by Russ Dickman.

Next up is a nice Open Star Cluster, M21(mag5.9). This beautiful shot was taken by former Utah Skies Astrophotographer of the Month, Al Kelly.

Next up is a monster of a Globular Star Cluster, M22(mag5.2). This is a BIG cluster... spanning 33'... about the size of the full moon. In fact, only Omega Centauri and 47 Tucanae are larger. Were this object higher in the sky, it would be THE globular cluster for us northerners. Unfortunately, it's pretty far south... so... we only get to glimpse it's greatness. This awesome shot was taken by Al Kelly.

Continuing along we come to another delicate Open Star Cluster, M23(mag5.5)

Changing speed... just a bit, we come to The Sagittarius Star Cloud, M24(mag4.6). This is not a cluster as we typically see. This is a star cloud... an extremely dense region... spanning about 2°x1°... roughly the size of the Andromeda Galaxy! What an awesome wide-field shot. This is a great place to simply "star-cruise" through the sky. Your eyepiece will be continually overflowing with stars. From time to time, you'll occasionally stumble over a gem.

Recovering from our divergence, we come to another nice Open Star Cluster, M25(mag4.6)

Continuing, we come to another fine Globular Star Cluster, M28(mag6.9). In fact, were this beauty not overshadowed by it's neighbor to the east (M22) it would be much better known.

Continuing, we come to another Globular Star Cluster, M54(mag7.7). Located over 70,000 light years distant, this is the most distant of Messier's Globulars. Of even greater interest is a 1994 discovery which seems to indicate that M54 is actually part of the Sagittarius Dwarf Galaxy... a galaxy which our own Milky Way is in the process of consuming!

Continuing, we come to yet another fine Globular Star Cluster, M55(mag6.3). This is one of the most southerly located globulars on the Messier List.

Continuing, we come to...yup... another Globular Star Cluster, M69(mag7.7). This is one of 3 Messier and 1 NGC globulars which are strung across the southern portion of Sagittarius.

Continuing, we come to Globular Star Cluster, M70(mag7.8)

Continuing, we come to the final Messier Object in Sagittarius...Globular Star Cluster, M75(mag8.6). This one might give you a hard time finding it as it is far away from the bright stars of the constellation in a relatively dark portion of the sky.

Continuing, we come to Diffuse Nebula, NGC6559. This awesome shot was taken by Robert Gendler. Robert, you may remember, is also a past Utah Skies Astrophotographer of the Month

Let's wrap things up with this weeks Utah Skies Challenge Object Irregular Galaxy, NGC6822(mag9). Also known as Barnard's Galaxy this is one tough object to observe. It's mag 9 brightness sounds easy, but.. it's fairly extended 10'x14'. The accompanying image was captured over a fairly long exposure.

Good Luck!

Ok... just one more... Utah Skies own Anthony Arrigo took the accompanying shot (6/28/03) from my campsite at 9400' in the Uintas. This was a 20 minute exposure using Fuji Provia 400 film centered on M20, the Trifid Nebula. The camera set at about 200mm f/4.5 mounted piggy back on top of a Losmandy G11.