CONSTELLATION GUIDE Last updated: 19 May 2001

"GO TO"....AQUILA
and Discussions of the Constellation Scutum
The Milky Way's Soaring Eagle of the Night / The Warrior's Lost Shield

From: sherrodc@ipa.net (Clay Sherrod)

In our tenth Constellation Guide, "GO TO AQUILA" of the series "GO TO GUIDES for the ETX and LX 90 Telescope Users" we will soar with eagles throughout the "great river" of the Milky Way galaxy. Aquila and its bright star ALTAIR are the southernmost of the dominant summer constellations and together with Deneb (Cygnus - http://www.weasner.com/etx/ref_guides/cygnus.html) and Vega (Lyra - http://www.weasner.com/etx/ref_guides/lyra.html) form the bright "summer triangle" so unmistakable in our northern skies. In addition to Aquila in this part of the sky, we find more southerly SCUTUM (the "shield"), a small but remarkably rich constellation often overlooked or mistakenly thought to be part of larger Aquila. The stray shield is that beaconing the warrior Hercules, who has lost his protective barrier in the many challenges he faced throughout Earth and sky.

It is through Cygnus and down into Aquila that the brilliant Sagittarius arm of our Milky Way galaxy is seen; when we gaze at this wonder, we are looking across a vast emptiness of space toward a star-and-nebula rich spiral arm of the galaxy, and the deeper we go toward the rich star clouds of Sagittarius, the closer we peer at the very hub of the incredible Milky Way and its 200 billion so-odd stars. Image that the earth is a planet on but one isolated star in an OUTER ARM of the galaxy.....as we gaze toward Aquila and Sagittarius, we are looking INWARD toward the nuclear hub of the galaxy of which WE are part. Looking the opposite way -toward Orion and Auriga in winter skies, we look in yet another direction and at yet another, less star-dense galactic arm leading OUT OF the spiral system of stars.

The next closest galaxy that "resembles" our own Milky Way galaxy is nearly 2.5 billion light years distant. Every star, planet, cluster, comet, asteroid, meteor, globular...that you see is in OUR galaxy; once beyond all that "stuff" there is NOTHING....barely a molecule, until you reach the confines of the Andromeda Galaxy. Imagine yet further that - as you enter that galaxy some 2.5 billion years from now as you travel at "warp one" (the speed of light) - you begin to see new stars, nebulae and all those things similar to that same stuff from our galaxy that you left behind. Yes, indeed, the "stuff" of which we are made of is all the same.....universally everywhere.

Although bordering the star-rich Milky Way and containing many wonderful star fields for low power and slow scanning on a dark night, Aquila is curiously void of spectacular deep sky objects and remarkable multiple stars that are noted in such great numbers nearby. Even the most famous object nearby is often mistakenly placed within the confines of the large eagle's outstretched wings and talons, but indeed the "Great Scutum Star Cloud' with its fantastically rich star cluster Messier 11 is nonetheless still in "Scutum" to Aquila's south.

Hence, we will include some discussion of that minor constellation here since one of the most remarkable regions of stellar density of our Milky Way is seen within its boundaries.

Click for full size version

Note from the sky chart included here that the CELESTIAL EQUATOR passes through the middle sections of Aquila and just north of tiny Scutum. This is the reading "0" degrees on your properly adjusted declination setting circle. All angles NORTH of this equatorial line are positive ("+") and all angular measures (declinations) south of the celestial equator are negative ("-"); hence you will see references in this "GO TO" GUIDE to both "+" and "-" declinations for celestial objects.

You will begin your "GO TO" journey into the Eagle's lair and into the great lost shield of the sky warriors via the bright star "ALTAIR", a nice bright yellow star that is commonly referred to in the "asterism" known as the SUMMER TRIANGLE, a nice wide shape bounded by the bright summer stars Deneb (Cygnus), Vega (Lyra) and Altair (Aquila). See our constellation "GO TO" TOUR for Cygnus at: http://www.weasner.com/etx/ref_guides/cygnus.html for a sky chart showing this spectacular summer marker!

Each GO TO object is discussed for your telescope regarding the type of conditions necessary for you to view it optimally for discern the very faintest details....double star challenges for each size telescope .....magnifications and aperture necessary for most objects, and much, much more. This is YOUR complete GUIDE to get you on your way to exploring this large and interesting constellation. ONE THING that I might add about the region in and surrounding Aquila: Although some interesting and "test" double stars are always included in the "GO TO" TOURS, there is a particularly wide range of very interesting double and multiple stars too numerous to list or mention here. Consult a good handbook, such as the "Burnham's Celestial Handbook," Vol. 1 for a very comprehensive list of locations, magnitudes and angular separations of these wonderful stars. There are many stars for EVERY telescope size and type.

Use this attached star chart and the following Guide as an excellent reference for your next star party itinerary, or a beginning for further study into the thousands of objects visible in this part of the sky. Truly these extensive Constellation Study Guides will most definitely put your AutoStar to work for you in the most efficient and enjoyable way possible! As a matter of fact, MANY AutoStar users are now programming their own "Tours" based on these guides, using each constellation as a separate GO TO Tour for the AutoStar library that can be added in or deleted through the main edit screen on your PC or MAC computer.

We hope you enjoy these comprehensive GUIDES to touring the constellations via your AutoStar and its computer-driven telescope. Each new installment is complete with diagrams, charts and illustrations that you will find nowhere else. Please let us hear YOUR feedback and your observations of each and every constellation after YOU have toured its vast reaches of our skies!

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YOUR AQUILA / Scutum CONCISE DIRECTORY OF INTERESTING OBJECTS -

There are literally thousands of fantastic objects in these two constellations, ranging from multiple stars, clusters, bright AND dark nebulae - from naked eye, to wide field, to telescopic - that is was very difficult to select (and limit) the number of objects for our "GO TO" TOUR. Only the best and in some cases, most challenging, objects are chosen for this brief tour.

I have chosen the finest 14 objects in this Aquila and Scutum to "GO TO" TOUR; as with all GUIDES, all objects listed below will be visible in all telescopes (some naked eye) from the ETX 60 through the LX 90; of course larger apertures may "show" an object a bit closer and "better," but frequently a wide field and low power view is more desirable than aperture. This is the case for MANY of these objects since we are looking directly into the very star-cloud-rich areas of our Milky Way galaxy. Indeed, I strongly encourage your to step away from the telescope often and scan the beautiful open skies and star fields with a good pair of 7 x 50 or 10 x 50 binoculars. You will be tempted to venture to your "dark sky site" for a full evening of laying back on a blanket and scanning the skies. The many deep sky objects in the Cygnus area even stand out to the dark-adapted naked eye, and the dark and bright star clouds emerge like in no other area. Once your eyes are fully dark adapted, you will even be able to see such wonders perhaps as the magnificent and very large "Scutum Star Cloud"....appearing as its namesake a very open and bright cloudy object that is huge in the open sky, sprinkled with thousands of tiny naked eye stars. It is within this magnificent cloud that the famous "Wild Duck Cluster" (really don't like that name for such a "royal" sight!) is embedded. Even the binoculars will show dozens of deep sky objects that cannot be fully appreciated in large telescopes with limiting fields of view!

The convenient sky placement of the large Aquila constellation lends itself well to very good and long-period observing for ETX and LX 90 users both north and south of the equator. When rising about dark in the east (mid-spring) it will remain in the sky throughout the night, transiting the meridian at about midnight during that season. All deep sky objects and difficult double stars are ALWAYS best observed when they are located nearly overhead (or as high in the sky as possible), thus requiring the observer to look through the thinnest portion of the Earth's "lens" of atmosphere and haze.

As with all of the "GO TO" TOUR constellation lists, I recommend a good star atlas and/or chart which will list all the finest objects, constellation-by-constellation. One very handy reference guide is the PETERSON FIELD GUIDE TO THE STARS AND PLANETS, which features complete lists with declinations, right ascensions, magnitudes, and all pertinent information for you to expand your observing horizons beyond this brief GUIDE.

Note that your AutoStar will NOT have every object listed on every constellation GO TO tour....this is intentional. You can access some of the most interesting objects of the sky directly from their coordinates. It is quite simple as you merely enter these coordinates as follows in the 10-step process:

1) Press the "MODE" key and hold down for 3 seconds and release;
2) Displayed will be the current Right Ascension and Declination of the center of field of view of where your telescope is presently pointed (assuming that you have properly aligned from "home position");
3) [NOTE: if you have the Meade electric focuser attached to any of the ETX or LX telescopes, holding down the "MODE" key will bring up the "Focus" command first....merely scroll (lower right scroll key) down one step to access the RA and DEC to enter your desired coordinates]
4) Press the "GO TO" button on AutoStar;
5) This will change the display and you will note the cursor blinking over the first digit of RIGHT ASCENSION (R.A.); merely use the number keys and dial in the R.A. of the object you are searching for;
6) When done, press "Enter;"
7) This moves the blinking cursor over the "DEC" coordinates;
8) [NOTE: the declination, unlike R.A., can be either positive or negative and you will see the "+" or "-" sign displayed depending on where your telescope is aimed at that time; if it is NOT the desired setting (plus or minus), merely use your arrow key to move the blinking cursor OVER the "+" or "-" sign and change by using either of your lower corner SCROLL KEYS;
9) Proceed to enter the DEC using number keys;
10) Press either "Enter" or "Go To" when finished and the telescope begins slewing to your desired object!!

The constellation tour Star Chart above (click on and save to a file on your PC; then open it and re-size to fit the page and print for a very handy at-the-scope star chart) will get you started on your journey for this constellation.

Following is the concise object list for your "GO TO" TOUR of Aquila and Scutum; you may wish to find the majority of the objects from the AutoStar Library (for example, you can easily go to the "Wild Duck Cluster" if you pull up "Object/Deep Sky/Messier Object/..type in '11'...." and then press "Enter", followed by "GO TO" to access my favorite beautiful galactic cluster. On the other hand, if you want to experiment and become a "better AutoStar user" try entering the exact R.A. and DEC coordinates of that object as described above after holding down the MODE key. You will find the accuracy of entered GO TO's to be somewhat less than those stored in AutoStar, but the capability of acquiring unlisted objects is fantastic!

OBJECT 1:
    very bright star - ALTAIR (alpha Aquilae) - R.A. 19h 48' / DEC + 08 44 - Magnitude:  0.8, very near star
OBJECT 2:
    very tough test double - ALSCHAIN (beta Aquilae) - R.A. 19h 53' / DEC + 06 17 - Mags:  3.9 & 11.4 
OBJECT 3:
    LX 90 test star - Zeta Aquilae - R.A. 19 03' /  DEC + 13 47 - Magnitudes:  3 & 12 (!) very tough double
OBJECT 4:
    ETX 90 test star - 23 Aquilae - R.A. 19h 16' / DEC + 01 00 - Magnitudes 5.5 & 9.5 -  Test for ETX 90!
OBJECT 5:
    Nice Double! - Pi Aquilae - R.A. 19h 46' / DEC + 11 41 - Magnitudes:  6 & 7 - good double for -90/-125
OBJECT 6:
    Variable star - Eta Aquilae - R.A.19h 50' / DEC + 00 52 - Naked eye/ETX 60/70, Mag. range 3.5 to 4.5
OBJECT 7:
    Wonderful variable! - R Aquilae - R.A. 19h 04' / DEC + 08 09 - Magnitude range - 6 to 11.7, 300 days!
OBJECT 8:
    Small galactic cluster - ngc6755 -  R.A. 19h 05' / DEC + 04 09 - Mag: 8.3, about 50 stars!
OBJECT 9:
    another galactic cluster - ngc6709 - R.A. 18h 49' / DEC + 10 17 - Mag:  8.1, nice, 30 stars
OBJECT 10:
    wonderful DARK nebulae -  B143 & B133 - R.A. 19h 38' / DEC + 11 00 - (for B142 in the "great rift")
OBJECT 11: (in Scutum)
    Great variable star -  R Scuti - R.A. 18h 45' / DEC (-) 05 46 - Mag. range 5.8 to 7.9, GREAT for ETX 60!
OBJECT 12: (in Scutum)
    "Wild Duck Cluster" -  Messier 11(ngc6705) - R.A. 18h 48' / DEC (-) 06 20 - Gorgeous 200 stars!!
OBJECT 13: (in Scutum)
    galactic cluster-  Messier 26 (ngc6694) - R.A. 18h 43' / DEC (-) 09 27 - Mag. 9.3, 20 stars, nice/small.
OBJECT 14: (in Scutum)
    globular cluster - ngc6712 - R.A. 18h 50' / DEC (-) 08 47 - Mag. 8.9, very small & interesting

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A VISUAL GUIDE TO OUR DEEP SKY OBJECTS IN AQUILA and Scutum

Object 1 - Very Bright Star - "Altair" (alpha Aquilae)
As usual, we are starting out Aquila/Scutum "GO TO" TOUR with the brightest member of the group. Altair, although uninteresting except for its brilliance in white-yellow grandeur, is a very peculiar and close star to our own sun. At magnitude 0.8, it is the 12th brightest star in the sky, partly because it is so close at only 16 light years. In many respects Altair is like our sun, but in MAJOR areas it differs greatly!

Altair (the "Eagle's Heart") is one of the fastest rotating objects known. It spins on its axis (making a rotation every 6.5 hours compared to our sun's 25 DAYS!) faster than even speedy Jupiter (9h 55m), and so fast that its sphere is actually flattened greatly from the spin, like an oblate or flattened basketball. It is about the same size as the sun and has an OPTICAL companion star of magnitude 10.1 (not a physical double) that might be seen with difficulty (due to the brightness of Altair itself) nearly due north (and a bit west) of the bright star. It is quite a distance, about four times the disk diameter of Jupiter as seen in the same eyepiece. Do not bother with any scope smaller than the ETX 125 as the faint companion will not be seen. Luck and imagination MAY give you a glimpse in the larger scopes.

Object 2 - "Alschain" - (beta Aquilae) - A Very Tough Double for the LX 90 and "maybe" the ETX 125
Although Alschain is a widely separated double star (12" arc) it is still a tough object because of the brightness of Beta Aquilae (magnitude 3.7) and the VERY dim companion at only magnitude 11.4. Any other star isolated against a dark background sky would be a relatively easy dark sky/100x object for the ETX 90....but not when so overshadowed ("overbrightened?") by such a bright star so close. The faint star is a red dwarf, but due to its faintness the color cannot be seen. In the ETX 125 (maybe with 220x) and perhaps a lot more easily with the LX 90, look for this very faint star DUE SOUTH of the brighter star.

Object 3 - Another Very Tough Double - Zeta Aquilae
To give you an idea on just how difficult it will be to see this star, note that it was DISCOVERED in the 26 inch refractor at the U.S. Naval Observatory and had gone unseen before. However, that being said, the very faint companion star to Zeta (magnitude 3.0) can theoretically be seen even in the ETX 90; but that is "theoretical." It cannot be seen at its 5" arc distance from the bright star even with the ETX 125; there is only a thread of hope with the larger 8" scope as well, but I have glimpsed this star on repeated occasions when the seeing is very steady and using powers in excess of 250x with 8" scopes of good quality. The faint star can be found (?) exactly northeast of the brighter star and VERY close; if you have a crosshair eyepiece, try blocking out the glare of Zeta with a cross hair and then look for the star. This trick works WONDERS in difficult double star observing!

Object 4 - A Very Nice Double for the ETX 90 and Larger Scopes - 23 Aquilae
You won't find this one in your AutoStar Library, so dial in the coordinates and try to find this magnitude 5.9 star and its 9.5 companion. Because of the star-rich region of Aquila, this star will be a bit hard to find,but once located, medium-high power (about 120x) in the ETX 90 and larger scopes will reveal the fainter star almost DUE EAST of the brighter component, separated by only 3" arc, making it not an easy target for the ETX 90, but certainly should be resolvable. It is a very nice contrast in brightness and worth the effort to find.

Object 5 - Pi Aquilae - Tough Test for the ETX 90! Good Double Star This pair, magnitudes 6 & 7 are a great test for the ETX 90, at a separation of only 1.4" arc; in some cases it MAY be a good test as well for the ETX 125. Try it out and see if YOU can split it! Look for the stars in a NE-SW orientation and VERY close and almost equal magnitudes. If you do not split it at first, make sure you have the correct star, as this is just below naked-eye visibility. Then go up to about 100x....if it still does not "open up" try 150x to 200x depending on the steadiness of your night air. That should do it!

Object 6 - Eta Aquilae - Very Nice Naked Eye Variable Star! ETX 60 and 70's ideal object!
This is a very nice Cepheid-type variable star (see http://www.weasner.com/etx/ref_guides/draco.html ) that likely is more accurate than your wristwatch at keeping time. Really. Does your Timex keep on tickin' to the tune of 7.17622 day accuracy? I think not. The Delta Cephei stars are pulsators that brighten as they expand their diameters (like a balloon getting larger) and dimmer as they shrink. However, unlike MOST Cepheid variables, Eta Aquilae exhibits a very interesting deviation as can be clearly noted in the light curve below:

Note the small "plateau" about one-half way as the star is diminishing in light. It last for nine hours and occurs with every dimming of the star; this is not a normal occurrence for Cepheid variables. The best way to observe this star is either with your lowest power on the ETX 60 and 70 or with the naked eye/binoculars. Since the star is relatively bright, comparison stars will be some distance off, but are clearly identified using the fine comparison and finder charts from the American Association of Variable Star Observers (AAVSO). These wide field "a" finder/comparison charts can be downloaded, saved to file, resized and printed in chart form from your computer. Because of its minor brightness changes AND the rapid period (it diminishes in less than one day!) there is NOT a dedicated chart for Eta Aquilae, by by linking to www.aavso.org you can access the many charts available for other nearby stars that will include this star in their widefield ("a") charts!

Object 7 - A Very Fine and Easy Variable to Follow! R Aquilae
This huge star is a pulsating "Mira"-type variable red giant star that may be about 600 light years distant (it is difficult to judge accurately distances of Long Period "Mira" variables). It has an nice magnitude variation of almost 7 magnitudes and is easily observable throughout its range with the ETX 60 and larger telescopes. However, the ETX 60 and 70 are the ideal telescopes of choice for observing such stars, which range from magnitude 6 to about 11, fully within the range of these telescopes throughout its cycle.

Notice how predictable the light changes in this star are from the sample light curve above. The period (total number of days from brightest through dimmest and then back to brightest again) is actually DECREASING on R Aquilae. Once over 350 days, the period is now just under 300 days! Thus, you should observe this star at most only about every week or two and report your observations routinely to the AAVSO at the link provided above.

For a good comparison star chart for this interesting long period variable, link to: http://charts.aavso.org/AQL/R_AQL/RAQL-B.GIF for a chart to make estimations of magnitude, and the link http://charts.aavso.org/OPH/X_OPH/XOPH-A.GIF as the finder ("a") chart for both locating the star and for estimating with brighter stars (naked eye) when at its brightest.

Be sure and note the incredible RED color of this star throughout its cycles. As one of the coolest stars known (all of its friends are constantly saying: "....man, you're the COOLEST star I've ever known...", R Aquilae is located in the "great rift", the dark star-obscuring cloud of the Milky Way, making its reddish color stand out even more vividly.

Object 8 - A Nice Small Galactic Cluster: NGC 6755
This is a relatively small (10' arc, about 1/3 the moon's diameter) but moderately bright (magnitude 8.3) cluster containing about 50 stars, most of which are too faint to individually see in all but the ETX 125 and LX 90 scope; even with those larger apertures, expect to see only 15 or 20 of the brightest members of this group on the darkest nights, with the remainder appear as a very dull background "glow." It is a very nice cluster, however, with some of the brighter stars visible in the ETX 90; the ETX 60 and 70 show this - and the following cluster, ngc6709 - as a faint round glow in medium-high power. This is a VERY distant galactic cluster, about three times further than the only-a-bit-brighter ngc6709.

Object 9 - Another Small but Nice Galactic Cluster - NGC 6709
Located due north and a bit west of ngc6755 is another galactic cluster that is very similar in appearance, but much easier to see the fine array of stars at medium-high magnification. Total, there are about 40 stars visible in this cluster with the LX 90, about 30 in the ETX 125 and some 12 visible in the ETX 60 and 70 at high (120x) magnification. Note particularly the brighter "double" star in the photograph below taken with a 13" astrograph (courtesy Lowell Observatory) seen at the lower right of the cluster. These two stars are the brightest members of the cluster, but several other brighter outer members are clearly visible. This is a nice object for very dark skies, one that is often overlooked in a very star-rich portion of the Milky Way.....you owe it to yourself to do some slow scanning through this area!

Objects 10 - Very Nice Dark Nebulae - The BEST for Amateur Telescopes: B143 and B133
Two of E.E. Barnard's "dark nebulae," these light-blockers are excellent objects but require VERY dark skies and very low power, wide field views. The Milky Way is so incredibly rich with very faint stars and rich nebulosity in this region that dark nebulae on a very deep dark night really can stand out. B143 is located at R.A. 19h 38m; DEC +11 degrees 00m and is most definitely the easiest to find and see. Look for it only 1.5 degree WEST of gamma Aquilae; it is that easy to find. On the other hand, B133 (R.A. 19h 05m; DEC -06 degrees 55m) is not as conspicuous and requires your GO TO function to locate. Look for it as a place where "stars ain't" as they say. In the rich Milky Way, both stand out clearly as black spots against the star field behind.

Dark nebulae is actually light-absorbing dust that rests amidst the spiral arms of the galaxy; indeed, were it not for such dust, the intense light and radiation from the center of our galaxy would make life difficult if not impossible throughout the galaxy! The dark dust is BETWEEN you and the stars blocked behind it that you merely cannot see.

Look in your lowest power with a fully dark-adapted eye (at least 15 minutes or more) at B143 for two lobes or "prongs" that can be clearly seen in most scopes. This double nature can even be seen in binoculars as the dark nebula is very large, about the size of the moon. B133 is about 1/3 that size and a bit more difficult to make out at first; moving the telescope very slightly back and forth across the field will assist in your eye adapting to such a low contrast object.

Object 11 - Another Excellent Variable Star! R Scuti (in Scutum)
This is another very fine classic variable star that is well worth keeping up with, and easily observable - if not the BEST - star for the ETX 60 and 70 telescopes, varying between magnitudes 5.8 and 7.8 in a period of only 140 days; thus it is a good idea to record this star's brightness about once per week. Actually, if you are in a hurry, you can easily make your magnitude estimates with some good 7 x 50 or 10 x 50 binoculars! However, you will be missing the incredibly stunning field of stars surrounding this area. It is a very rich region near the Milky Way arm.

R Scuti is a classic and easy-to-follow "semi-regular" RV Tauri type star that has an "overlying" period of some 140 days, but also exhibits considerable unpredictable and erratic behavior within that period.

Download and save to file this link from the AAVSO for R Scuti as your observing and locating chart for this nice variable: http://charts.aavso.org/SCT/R_SCT/RSCT-B.GIF. You will need to go to file and resize this chart to make it suitable for full page printing.

Notice in the figure below the remarkable difference in the light curve for R Scuti than for our preceding Long Period and Cepheid variables. R Scuti is only MODERATELY regular as can clearly be seen! And that is what makes this star so remarkable exciting to observe! In addition to the regular large brightness fluctuations of not-even "regular" periodicity, there are innumerable minor outbursts and unexpected variations to make this a truly exciting star to keep up with.

Note the deep minimum periods (marked with the red "a") that occur on a semi-regular basis as well as all the minor irregular fluctuations in between. The "primary period" is about 144 days, but the star is so irregular that much can happen in that interval. You should make an effort to monitor this star to assist in the studies that are underway on it and other stars like it. Send your observations once per month (observe about once weekly) to: www.aavso.org to have them included in the growing body of knowledge of the semi-regular variable star groups.

Objects 12 - the BEST galactic cluster of the summer - Messier 11 - "The Wild Duck Cluster"
Messier 11 is like Saturn when you see it for the first time in your telescope....you will never forget the beautiful view. This cluster almost resembles a sparse globular cluster but is technically a very RICH galactic cluster some 5000 light years away; one can only image what this remarkable object would look like if moved to the distance of our CLOSEST star clusters, such as the Pleiades, only 450 light years distant! Even at that great distance, the LX 90 8" scope can reveal about 250 stars down to magnitude 13.8 easily; only slightly less stars can be seen with the ETX 125; expect some 175 plus stars with the ETX 90 and using medium high magnification with the ETX 60 & 70 you should be rewarded with at least 100 or more beautiful stars....all about the same magnitude! Using medium magnification really reveals the beauty - and more stars - of this cluster. In reality this wonderful object contains an estimated 850 to 1000 stars down to magnitude 18.

The first thing you will notice about M-11 is the interesting yellowish bright star right in the middle of the cluster, obviously MUCH brighter (magnitude 8.0) than the stars of the cluster. There is a reason for that. This particular star is a FOREGROUND object....it is NOT part of the cluster, but located somewhere between M-11 and Earth. It is this star, on a very dark night, that provides a near-3-D look to Messier 11 and its surrounding rich stellar neighborhood. It was the famous observer "Admiral Smythe" who gave this object its aviatric name "Wild Duck Cluster," when he remarked in his observing notes that this remarkable object appeared to him as a "....flight of wild ducks" in the sky.

Object 13 - Galactic Cluster Messier 26 (a mere kid-brother to fabulous M-11)
Messier 11 is wonderful, and is a tough act to follow, and is only magnitude 9.1 and about 10' arc across; thus it appears as a disappointment if you have just looked at Messier 11! With a good dark night and the ETX 125 or LX 90 about 25 brighter stars can be seen out of maybe a total of 125. About a dozen are visible in the ETX 90 and the brightest 9 are clearly visible in the ETX 60 and 70 under medium high power. Messier 26 is truly smaller and contains less stars than M-11, as both are almost the same distance away.

Object 14 - A Small, but Fine Globular Cluster - NGC 6712
A lone globular cluster - but one that is worth checking out - is located in this "GO TO" TOUR, this being in Scutum. At magnitude 8.3, it is a fairly bright and easily-found object in the ETX 90 and larger scopes; it appears as a very tiny and faint "fuzz ball" to the ETX 60 and 70. Medium power (about 30x per inch) is required to really get a good look at this object, but even with the 8" no resolution is possible, this object being very distant. On a very dark night and about 220x, both the ETX 125 and LX 90 should see some "granulation" of the small disk (only 2.5' arc) of light around its edges, these being the red giant stars that are so faint as to be just out of reach of our range of telescopes.

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WANDERING ABOUT....YOUR NEW "USER OBJECT" IN AQUILA

Since the two dark nebulae (Barnard's B143 and B133) are perhaps the easiest and best such objects for amateur telescopes, AND you may want to try your hand at some piggyback astrophotography (see my "Piggyback Astrophotography" guide at http://www.weasner.com/etx/ref_guides/astrophotography.html). LET'S LOAD both these dark nebulae INTO OUR USER OBJECTS! Take your Autostar and key in the coordinates for each as given above.

On AutoStar, go to: "Select/Object [enter]...." scroll down to "User Object" [ enter]. Now enter the coordinates given above for "B143", using the number keys on AutoStar. After entering the coordinates and pressing "Enter" yet again, scroll down one and you can list the magnitude of the object as "0"[Enter]. Now go back and mode back to "USER OBJECT / Add...." and enter the coordinates and information for B133 as well.

Next Constellation GO TO" TOUR Installment: SAGITTARIUS, the "Archer," and the home of the most fantastic view of star clouds this galaxy has to offer from Earth! We will explore the Omega nebula, the Trifid, the great Sagittarius star cloud, and peer right into the galactic center and its impacted masses of stars and dark nebula. In the meantime, hone up on your piggyback astrophotography skills with your ETX or LX 90....this is one area of the sky where a simple camera set to "bulb" (B) and a five minute exposure can reveal the true wonders of our Milky Way galaxy! In this wonderful majestic soaring celestial Eagle we will examine the rich and thick clouds of stars that comprise the most dense portion of our Milky Way galaxy as we move every-so-closer to the galactic center in the famed archer Sagittarius.

Good Observing and explorations of this wonderful world of deep space!

P. Clay Sherrod
Arkansas Sky Observatory
Conway / Petit Jean Mountain
Arkansas

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