Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Classic Messier

beginner classic dso observing report observing refractor
  • Please log in to reply
194 replies to this topic

#76 AllanDystrup

AllanDystrup

    Apollo

  • *****
  • topic starter
  • Posts: 1408
  • Joined: 27 Sep 2012
  • Loc: Denmark

Posted 10 June 2016 - 04:23 AM

     For comparison, here's an observation I made of M13 almost 2 years ago, when dark nights had returned in September. The observation was done with my small CZJ Zeiss E50/540 mm refractor at 51x magnification. The view is -almost- comparable to my recent observation with the 80mm Vixen, done in the twilight zone (although of course the image scale is better for the 80mm)...

    

     I'll need to re-observe some of these globs above the Milky Way plane, in the upcoming fall, 2016...

 

M13 E50.540 BlackL-S.jpg

 

Allan


Edited by AllanDystrup, 10 June 2016 - 09:52 AM.

  • CharlieB, Sasa and Redbetter like this

#77 AllanDystrup

AllanDystrup

    Apollo

  • *****
  • topic starter
  • Posts: 1408
  • Joined: 27 Sep 2012
  • Loc: Denmark

Posted 10 June 2016 - 04:39 AM

M5

 

 

Meanwhile, here's my observation of the M5 Globular Cluster in Serpens Caput; Like the two Messier GSs in Hercules and the M68 Hydra GC, this glob is high up above the Milky Way plane, at a medium distance from the Sun. M5 is well positioned for observation from my backyard, but M68 is quite a bit further down S of Corvus in Hydra, and already way past the meridian and sinking in the W, when Nautical Twilight finally appears after midnight, -- so that one will have to wait till fall.

 

-----

 

     It’s a summer night in early June, 01:45 local time.  It’s still nautical twilight up here, at 56° N latitude, but a globular cluster should be within reach of my 80mm refractor. I decide to go for M5 in Serpens (Caput), starting my star hop from Alpha Serpens (Unukalhai – or Unuuk al Hay, The Neck of the Snake. Gotta love those old Arabic names...). From Apl Ser i sweep with the 10x 60mm finder 8° SW, until I get a nice, kite/diamond shaped asterism in the field of view. M5 is clearly seen in the finder (as well as in my 8x30 bino) as a faint, nebulous hazy spot, just off the N tip of the kite.
    
    At 24x in my ATC K-40mm eyepiece, M5 shows up as a hazy ball, that appears grainy with averted eyesight. Clicking the magnification up to 60x @ 0.7° FOV (CZJ O-16mm), I settle on this view to frame my drawing. The 5m star 5 Ser is seen at the SSE end of the FOV, forming a triangle with two fainter (10m-11m) stars to the NW.  At the center is M5, that appears slightly elliptical, leaning towards NE. The brightest stars (Mvis 12.5m) should be resolvable in my 80mm refractor, but given the less than optimal observation conditions, I can only resolve what looks like one individual star (but is actually a pair of red giant stars) in the SE part of the cluster.

    

M5 BlackL-CropS.jpg

    

Link to full ->Obs. Report<-

 

Allan


Edited by AllanDystrup, 10 June 2016 - 04:52 AM.

  • CharlieB, DHEB and Sasa like this

#78 sparrowhawk

sparrowhawk

    Ranger 4

  • *****
  • Posts: 369
  • Joined: 02 Sep 2007
  • Loc: North Dakota / United Arab Emirates

Posted 24 July 2016 - 05:07 PM

Hi Alan,

 

Do you have an astronomy blog with your observations posted? I really enjoy reading your reports and seeing the methodical approach you take to observing. 


  • AllanDystrup likes this

#79 AllanDystrup

AllanDystrup

    Apollo

  • *****
  • topic starter
  • Posts: 1408
  • Joined: 27 Sep 2012
  • Loc: Denmark

Posted 26 July 2016 - 02:11 AM

Hi Shawn,

Thank you for the kind feed back, much appreciated :)

 

I have considered gathering my obs. reports on a blog, -- I do have them much more organized in proper categories on my pc, and would like to present that on the web. Just haven't got around to that, yet...

 

Meanwhile, here's the report from my latest observation, of :

 

-------------------------------------------------------------------------------------------------

 

M51, The Whirlpool

 

     ”Mad dogs and englishmen, walk in the midday sun...”. Thus wrote Kipling somewhere, -- I forget the context, but the line came to mind this summer night, when trying to catch M51, the Whirlpool galaxy. ”Mad dogs and danes, observe in the midsummer night...”.

 

     The star hop to M51 is easy : from the end of the Dipper’s handle (Eta UMa) -> 2° E to 24 CVn, then -> 1.5° S to a triangle of 7m stars ; M51 is just east of the S corner of this triangle. The conditions this early morning (00:30 Local DST) are however rather bad: though the transparency and seeing are just above medium, the cocktail of a Bortle red suburban backyard, nautical summer twilight, plus a 73% moon at 18° altitude in the SE, all this combines to the effect that I can’t even (as possible in autumn and winter) spot the galaxy with my 10x56 bino.

 

     Now switching to the Vixen FL-80S/640 refractor, and using my ATC K40mm finder eyepiece, for 24x @ 1.7° FOV, i can just glimpse a faint nebulous area at the proper location of M51, -- but even this requires an effort plus averted vision. No chance of producing a drawing of any value under these circumstances!

 

And then again...

 

     Switching to my R2 eyepiece, I immediately see two bright hazy stellar cores, each surrounded by nebulosity. Adjusting the integration and gain, structure starts to emerge in the nebulae (106x @ 0.3° FOV). I sit down and start to make a drawing: the face-on galaxy NGC 5194 (aka. M51a) displays 2 obvious, grand spiral arms, while the dwarf galaxy NGC5195 (M51b) shows a couple of clearly brighter lines (like eyelids) around the lenticular core. The arms of M51a show angular bends plus hints of ”knotty structure” (starburst regions), both the result of close gravitational interaction with M51b.

 

 

M51-RAW-Black-Crop.jpg

 

 

     Comparing my drawing to that of Stephen J. O’Meara in his book ”The Messier Objects”, I can see much more detail  in M51 (with the exception of the bridge between M51 a-b) with my 3” refractor and R2 Eyepiece from a NELM 5m sky, than he was able to with his 4” TV Pronto refractor from a pristine NELM 8m sky (3.600 ft  up, at Volcano, Hawaii), ”where the Milky Way is bright enough to cast shadows...”    

 

     Some are questioning, whether this kind of observation can be called ”visual”, arguing that only photons collected by glass should fit this definition. I totally disagree with this attitude. In my view, any personal registration and description of an object (be that textual or graphic) done by viewing it ”real time” at the telescope under the night sky is ”visual astronomy”. I don’t care what image itensifiers are used, -- more aperture, a ccd+lcd or a NV eyepiece...   If I can get a view of M51 in my small 3” refractor matching that of a bulky 18” Dob, I will go with that, especially when the observing conditions are otherwise impossible.
 
Allan

 

(PS: will post a link to the full obs. report here, soon)


Edited by AllanDystrup, 26 July 2016 - 09:53 AM.

  • photiost, xavier and CharlieB like this

#80 Sasa

Sasa

    Vanguard

  • *****
  • Posts: 2356
  • Joined: 03 Nov 2010
  • Loc: Ricany, Czech Republic

Posted 26 July 2016 - 02:19 AM

Allan, amazing, your drawing through humble 80mm shows rougly how I saw M51 through 250mm Dobson under 6.0 mag sky.

#81 Sasa

Sasa

    Vanguard

  • *****
  • Posts: 2356
  • Joined: 03 Nov 2010
  • Loc: Ricany, Czech Republic

Posted 26 July 2016 - 07:56 AM

I missed in the morning the part about camera involved in the process. That explains a lot. I have no problem if people are using cameras for night observing. Definitely not my cup of tea, but whatever makes people happy under night sky is fine.

#82 AllanDystrup

AllanDystrup

    Apollo

  • *****
  • topic starter
  • Posts: 1408
  • Joined: 27 Sep 2012
  • Loc: Denmark

Posted 26 July 2016 - 09:09 AM

     :grin: Sasa -- that is a common reaction from die hard conservative visual observers. I've just had a lengthy discussion with Thomas (Astrojensen), and we don't agree on what constitutes "visual" observation.

 

     My take on this issue is, that "visual" is using the eye/brain to coax out details of a real time image of the universe, under the night sky. The image may be a naked eye view, but typically it is enhanced and intensified, conventionally by a larger aperture than the pupil, using refraction/reflection in glass. More modern technicques (CCD, NV) allow further image intensification using a CCD or photomultiplier -- it is the very same image, mind you, as you observe with your glass eyepiece, and you use the very same observation techniques, but the S/N ratio of the image is much improved, and the details you can see for yourself (I repeat: in real time), and the information you can learn is likewise much increased.

 

   This early morning my choice was: to see NOTHING in my 3" refractor (but a faint nebulous shadow of a galaxy, or to see what I have drawn, using the R2. I chose the latter, for this observation...

 

Allan


Edited by AllanDystrup, 26 July 2016 - 01:32 PM.

  • xavier and OC Telescope like this

#83 sparrowhawk

sparrowhawk

    Ranger 4

  • *****
  • Posts: 369
  • Joined: 02 Sep 2007
  • Loc: North Dakota / United Arab Emirates

Posted 26 July 2016 - 12:21 PM

I guess I missed this in earlier posts. What is an R2?

#84 AllanDystrup

AllanDystrup

    Apollo

  • *****
  • topic starter
  • Posts: 1408
  • Joined: 27 Sep 2012
  • Loc: Denmark

Posted 26 July 2016 - 12:34 PM

Google "revolution imager r2".
There are other options for electronically assisted astronomy.
Check the EAA forum here at CN.

Keep an open mind, and
Have fun! :-)

Allan
  • OC Telescope likes this

#85 sparrowhawk

sparrowhawk

    Ranger 4

  • *****
  • Posts: 369
  • Joined: 02 Sep 2007
  • Loc: North Dakota / United Arab Emirates

Posted 26 July 2016 - 03:05 PM

Google "revolution imager r2".
There are other options for electronically assisted astronomy.
Check the EAA forum here at CN.

Keep an open mind, and
Have fun! :-)

Allan

Ahh, fascinating. I didn't realize you were using EAA (I keep thinking Experimental Aircraft Association) but given the detail in the sketches for the size of refractor that makes sense.

So you are sketching from the image on the LCD?

I take it there is some debate about EAA and if it can be considered pure visual observing?

Edited by sparrowhawk, 26 July 2016 - 03:34 PM.

  • AllanDystrup likes this

#86 AllanDystrup

AllanDystrup

    Apollo

  • *****
  • topic starter
  • Posts: 1408
  • Joined: 27 Sep 2012
  • Loc: Denmark

Posted 27 July 2016 - 02:48 AM

...
So you are sketching from the image on the LCD?

I take it there is some debate about EAA and if it can be considered pure visual observing?

 

     Yes, the sketch of M51 was done directly from my small "Starshoot LCD/DVR" screen, using the R2. I have the R2 as "just another eyepiece" next to my ATC K40mm finder ocular in my Zeiss turret. I can click back and forth between the eyepieces, from glass to R2/LCD, as I prefer.
    
     In viewing the image at the telescope focal plane, the process of exploring, studying, interpreting, sketching and communicating what I see live at the telescope, -- this process is *exactly* the same, whether I use image amplification with a glass ocular or with the R2/LCD.

 

     In fact the only difference between a passive, traditional (ocular) and active, modern (electronic, photonic) amplification, is the enormous gain in resolution and detail you get with the latter. This is essential to me in a LP Red zone environment, and especially when observing from 56dg N latitude, where the summer nights are in perpetual nautical twilight.

 

 

     Is there debate about "pure visual" and EAA? You bet!

 

     Some consider real time/live EAA "cheating". It breaks the limits of gain and resolution imposed on your instrument using passive glass only. Some feel it takes out the sport of pressing your finely honed observing techniques to the utmost, showing just how deep and detailed you can go with your top tuned glass and 25 years of training. Showing how good an observer, you are. EAA is like riding a motorcycle in Tour de France, "not fair!".

 

     I do understand that argument, and respect it. There is a sport and a pride in fine tuning your equipment and skills to the extreme, yielding the most outstanding, supreme observing achievements. I bow to that, any time.

 

     But there is an other dimension. My most used instrument currently is my portable Vixen FL80S/640mm F/8 refractor on a Zeiss Ib GEM / 2V tripod mount. It is a light grab/go rig, with a fast setup/tear down and cool down time. I use it all the time in my red suburban backyard and our yellow zone weekend cottage. I use it so much, exactly because it is so light, versatile and easy. Yes, I would like considerably more aperture, but my location, my observing preferences and conditions simply do not allow it.

 

     I do however want to dive into and explore and experience our surrounding universe with the most detailed views I can possibly squeeze out of my 80mm. And I don't really care about "pure" in this context, I have no emotional attachment to glass only. This is where EAA enters the scene. If I have the options in the depths of our nordic summer night of "purely" seeing... nothing, or with EAA seeing details of the colliding galaxies of M51, -- well, you know my choice.

 

     Enough said on this subject! (but you DID ask :grin:). For further discussion, I'll refer you to the EAA forum here on CN.

 

     Next up will be this nights observation of the globular M56 in Lyra. -- You will be able to compare the details I have observed in this globular using the R2, with my previous observation reports on globular clusters.

 

Allan 


Edited by AllanDystrup, 27 July 2016 - 03:08 AM.

  • sparrowhawk and OC Telescope like this

#87 sparrowhawk

sparrowhawk

    Ranger 4

  • *****
  • Posts: 369
  • Joined: 02 Sep 2007
  • Loc: North Dakota / United Arab Emirates

Posted 27 July 2016 - 08:05 AM

Thanks for the additional info! I started reading some of the EAA posts last evening. Personally I like the challenge of using smaller refractors. Adding the EAA device seems to redefine where the limits a small refractor are found.

 

I can sympathize with the perpetual daylight right now. At 46-deg 52' north we aren't getting many hours of dark time either currently. You're at 56-deg north? I didn't realize Denmark went that far north, unless you've taken Island back?  :)



#88 AllanDystrup

AllanDystrup

    Apollo

  • *****
  • topic starter
  • Posts: 1408
  • Joined: 27 Sep 2012
  • Loc: Denmark

Posted 27 July 2016 - 09:07 AM

I am just north of Copenhagen, at 55dg 53' N.

The northernmost point in Denmark is close to 58dg N ... Or in fact, to be precise, 83dg 30' N !

Huh??? Well, Greenland is still a part of the Danish Kingdom, so if you go to Oodaap Qeqertaa, that's pretty much as far north as it gets, without stepping out on the ice of the N Polar sea...  :shocked:


Edited by AllanDystrup, 27 July 2016 - 09:12 AM.


#89 sparrowhawk

sparrowhawk

    Ranger 4

  • *****
  • Posts: 369
  • Joined: 02 Sep 2007
  • Loc: North Dakota / United Arab Emirates

Posted 27 July 2016 - 12:44 PM

We are may be family then. I have relatives that live north of Copenhagen, near where the bridge to the land of Volvos is. :)

I haven't been to Denmark since the late 90's, forgot that it did go that far north. 🙈
  • AllanDystrup likes this

#90 AllanDystrup

AllanDystrup

    Apollo

  • *****
  • topic starter
  • Posts: 1408
  • Joined: 27 Sep 2012
  • Loc: Denmark

Posted 28 July 2016 - 07:47 AM

M56 (NGC 6779),
"Snowball" Globular Cluster in LYRA

 

     It is end of July, just past midnight local time, and I’m still deep in the Nordic summer nautical twilight. The transparency is variable due to drifting clouds, but quite good in between, and the seeing is above medium. I am however observing from my Bortle Red suburban/urban transition  backyard, and there’s a 50% (22dy) moon just rising in Taurus, albeit still low on the E horizon. The NELM is 5.0m (SQM 17.9), so I decide to go for a globular cluster with a reasonably high altitude; I choose M56, which is well placed for observation, at 64° Alt on the meridian due S .

    

     The star hop is easy : from Albireo (Bet Cyg), -> up 2° NW to 2 Cyg, then barely another 2° WNW to a nice figure "7” asterism of 7m stars; Just E of the 6m star at the base of this asterism I can glimpse a tiny hazy spot in my 10x56 bino: M57.

    

     I now plan to compare visual real-time observation of this object, using both traditional Zeiss Jena orthoscopic glass eyepieces for magnification, and also ”cheating” by using a R2 ccd/lcd for an intensified view. I will be using my Vixen FL80S/640mm F/8 fluorite apo for the comparison. The CZJ 10-O gives me 96x at 0.4° FOV, while the R2 yields approx. 106x @ 0.6° FOV. This is using a 1.5x GPC/Barlow for both, plus a 0.5x reducer for the R2.

    

     I start with the R2, set at fixed shutter/integration 256x (5s), gain at 24dB and no internal stacking. I can easily sketch around 200 brighter field stars in the central part (ca. 30’) of the FOV. The cluster itself is loose, with the brightest members resolved to more than 50 individual stars, gathered in an irregular ball with at least five chains of stars arching out in all directions. The light of the fainter stars in the core of the cluster blend into a nebulous, roughly spherical glow, brightest in the central 5’, then fading out to almost 10’.

 

M56-R2-Black-Crop.jpg

    

     The brightest stars in M56 are of 13m, while the 25 brightest members have an average visual magnitude of 15m.  With an optical limiting magnitude for my 80mm refractor of ~13m, I should - under optimal conditions - be able to resolve maybe a handful of stars in this cluster using traditionall glass eyepieces (requiring 8” or larger aperture for a resolution down to 15m). We’ll see about that...

 

----------

<Glass ocular observation of M56 – See below>

 

Link to ->Obs.Report<-

 

Allan


Edited by AllanDystrup, 29 July 2016 - 07:32 AM.

  • photiost, DHEB, Sasa and 1 other like this

#91 AllanDystrup

AllanDystrup

    Apollo

  • *****
  • topic starter
  • Posts: 1408
  • Joined: 27 Sep 2012
  • Loc: Denmark

Posted 29 July 2016 - 03:55 AM

M56, The Snowball Glob -- Continued

 

 

     It’s just past midnight, one day after my previous observation of M56 with the R2 ccd/lcd. The observing conditions are an almost exact match to the previous night, and so I have an excellent opportunity to compare the”light intensified view” (R2) with a traditional ”glass magnified view” (Ocular). For eyepiece i choose my CZJ Zeiss 10mm orthoscopic, which gives a view (96x @ 0.42° FOV) that is close enough to that of the R2 (106x @ 0.6°) for a good comparison.

 

     Looking into the eyepiece, I first notice that the FOV is a good match to that of the R2; I immediately recognize the main field stars, and am able to draw ca. 40 bright stars in the FOV without effort.

 

     Studying the details of M56 is much more demanding. I see a globular with an irregular outline of the halo and a relatively faint core. The central area of the glob is clearly mottled, and with long time, persistent and focused observation using peripheral vision, I can glimpse 4-5 stellar points in the core area, glinting in and out of sight. I am not with certainty able to place these stellar points on my drawing, so I settle at poking my pencil at 4 points, locating the stellar glimpses to the best of my ability. This is in contrast to the R2, where each and every stellar point on my drawing was observed with certainty on the lcd at the telescope (-- though drawing the central core of the glob still did take some time and effort!).

 

M56-CZJ10mm-Black-Crop.jpg

 

     So this is the best "glass view" of M56, that I was able to get this early morning -- but it must be emphasized, that the drawing was produced at 56° N lattitude, in nautical midsummer twilight, with a 28% moon just peeking up over the E horizon and with occational high cirrus drifting by.  When looking af Stephen O'Mearas drawing of M56 (in The Messier Objects, 2.Ed) I am frankly amazed at the details he succeeded in catching, albeit with a 4" refractor under pristine skies. Not close in etiher precision or detail, of course, to my "cheating" R2 drawing, but much better than my 3" glass view.

 

     It would be interesting, if others could post their drawing / observation of M56 here, for comparison.

 

Allan


Edited by AllanDystrup, 29 July 2016 - 07:41 AM.

  • photiost, DHEB and Sasa like this

#92 Sasa

Sasa

    Vanguard

  • *****
  • Posts: 2356
  • Joined: 03 Nov 2010
  • Loc: Ricany, Czech Republic

Posted 29 July 2016 - 05:17 AM

Allan, very nice comparison of two approaches. You saw pretty nice details through 80mm even under those unfavorable conditions.

 

Here are my observations, going up with the lens area (all from our light polluted backyard):

 

Nikon 8x40 bino:

- recognizable misty cloud. NW is brighter very nicely orange star. It makes the scenery very lovely. I have identified it later at home as BSC HR7302. It is a red giant with spectral type M0III.

 

Telementor 63/840:

-120x strongly mottled, several stars noticed in and near the external halo (one east from the center, the second less bright south of the center; not sure these are indeed cluster members)

 

ED100/900

- 75x first stars started to appear in the halo

- 176x: dotty, several stars at the periphery are well recognizable, several starry dots even in  the center

 

Vixen 130SS

-188x dotty over the whole surface. Averted vision shows many tens stars, these are definitely fainter than in M13. Brighter nucleus is without noticeable central condensation. It seems to be of a triangular shape. Faint halo about 3 times larger than the brighter central part, estimated dimension is about 6'. There are several fainter stars in the halo as well.


  • sparrowhawk and AllanDystrup like this

#93 AllanDystrup

AllanDystrup

    Apollo

  • *****
  • topic starter
  • Posts: 1408
  • Joined: 27 Sep 2012
  • Loc: Denmark

Posted 31 July 2016 - 12:36 AM

Hi Sasa -- thank you very much for adding your observing notes on M56, --
very interesting to compare our experiences at the telescope.

 

     M56 was clearly visible as a hazy spot in my 10x56 bino, as well as in my 10x50 finder scope. The orange star you mention is indeed 5.88m HIP-94630 (or HR-7302), at the base of the figure "7" asterism. M56 is rather diffuse and dim, but recognizable (I think) as a globular cluster in 50mm optics. I expect it might even be detectable in my 8x30mm bino under excellent skies, -- I'll try that, when the oportunity arises.

 

     My observation of M56 using the 80mm Vixen + CZJ 10-O eyepiece fits nicely between your 63 and 100mm scopes: pale irregular outlined nebulosity, 5 obvious stars in the halo (some of them foreground stars?) plus a strongly mottled center with a handful of tiny stellar glints, *just* at the limit of vision.

 

     My sketch with the R2 in my 80mm is closer to your 130mm observation. Interesting! :)

 

Allan


Edited by AllanDystrup, 31 July 2016 - 03:57 AM.


#94 AllanDystrup

AllanDystrup

    Apollo

  • *****
  • topic starter
  • Posts: 1408
  • Joined: 27 Sep 2012
  • Loc: Denmark

Posted 04 August 2016 - 10:23 AM

M11, the "Wild Duck"

Open cluster in Scutum

 

 

   It’s a cool, calm late summer early morning in the start of August, ½h past midnight local summertime. We now have a couple of hours with astronomical twilight, centered around 01:00  local DST, here at 56° N latitude, and as there’s no moon this morning, and the transparency and seeing are above medium (NELM ~5.2), this is a good opportunity for Messier hunting. Sagittarius has just crossed the meridian, so I load up my Zeiss Amici turret with CZJ orthoscopic eyepieces plus my R2 eyepiece cam, and point my Vixen FL-80S/640mm refractor towards Scutum.

 

   I first sweep my 10x56 Zeiss Bino, from the tail of the Eagle (Lambda Aquila) ca. 3° W; In the 6° TFOV of the bino I immediately catch the glowing triangular shape of the ”Wild Duck” open cluster M11 (east of Beta Sct), and a good 3° further south I can see the much smaller and fainter glow of ”The Kite” OC M26 (east of Delta Sct).

 

     The star hop is easy, using my ATC K-40mm EP (24x @ 1.7° FOV): from Lam Aql -> SW along a line past 12 Aql and Eta Sct to M11. There’s one bright 8.5m star in the center of the cluster, plus a nice pair of 9m stars just SE of the cluster. Switching to my R2 live view video eyepiece (110x @ ~½° FOV), I see that the central part of the cluster contains a score of 10m-11m double stars, plus half a score more forming small triple and quad constellations. More than a hundred fainter 12m-13m stars pepper the central core, some lining up in chains meandering out from the center. Two chains seem to delimit the cluster towards the NW and the S, thus giving it a fan / wedge-shaped outline (what led Admiral Smyth to liken it to a ”flight of Wild Ducks”).

 

 

M11-R2-Black-S.jpg
(N up, W right; -- Click for larger view...)

 

Allan

 

(Link to full Obs. Report will be posted later.)


Edited by AllanDystrup, 04 August 2016 - 10:41 AM.

  • sparrowhawk, xavier, mdowns and 4 others like this

#95 AllanDystrup

AllanDystrup

    Apollo

  • *****
  • topic starter
  • Posts: 1408
  • Joined: 27 Sep 2012
  • Loc: Denmark

Posted 05 August 2016 - 06:13 AM

M26, "The Puffball"
Open Cluster in SCUTUM

 

 

     Continuing my observation of the Messiers in Scutum, I now click back from the R2 ccd to my ATC 40mm finder eyepiece (24x @ 1.8° FOV); I pan the field W past a small 4-star asterism (with the rectangular outline of a skewed box), then S ca. 3°, following a line of 6m-7m stars flowing down towards Alp Sct. When I have both Alp Sct and Del Sct in the field, I look just E of Del Sct, where I find the faint glow of M26.

 

     Coming directly from M11, the M26 open cluster looks sparse at 24x, -- mainly a kite or diamond shaped asterism formed by one 9m star plus four ~11m stars. Clicking up the magnification to 96x (10mm CZJ Ortho, 0.4° FOV) reveals around a dozen fainter (down to 12m) stars on a hazy background of unresolved cluster members.

 

     Switching now to the R2 ccd/lcd (~110x @ 0.5° FOV),  the view explodes in a wonderful myriad of <12m stars, the brightest of which are arranged in chains swinging out from the central diamond – I get the impression of a puffball mushroom, with a puff of spores shooting up N, and being blown eastward by an invisible stellar wind. -- ”Puff, the magic puffball”... What a wonderful sight!

 

M26-Black-Crop-S.jpg

 

Allan


  • sparrowhawk, mdowns, Sasa and 1 other like this

#96 AllanDystrup

AllanDystrup

    Apollo

  • *****
  • topic starter
  • Posts: 1408
  • Joined: 27 Sep 2012
  • Loc: Denmark

Posted 06 August 2016 - 01:48 AM

M18, The "Black Swan"
OC in Sagittarius

 

 

    It is now 02:30 local DST, as I continue my observation of the Messier objects in the inner part of the Sagittarius arm:  From M26 just E of Del Sct, I first pan my ATC K-40mm finder eyepiece further SSW, past a pair of 5m-6m stars, until I hit Gamma Scuti (easily recognizable by a triplet of ~6m stars arranged in a ”Mickey Mouse head” asterism, E of Gam Sct).  From Gam Sct, I  continue to slide SSW, just 1 FOV (2°), until I have both M17 and M18 in the view.

 

     In my 10x56 bino, M18 shows up as just a small, nebulous knot of stars. The 40mm finder eyepiece view (24x) reveals a sparse cluster, with a handful of ~9m stars arranged in a ”number 2” figure (upside down, in my refractor). O’Meara named M18 the ”Black Swan” OC because of the arrangement of its central stars, which is indeed reminescent of the main outline of the glowing nebulosity of M17, just 1° due N.

 

M18-BLACK-CropS.jpg

 

     From the basic skeleton outline, O’Meara went on to imagine and sketch a full blown Black Swan, sailing the shores of the Sagittarius Arm, like a shadow of the White Swan above.  I can see that Black Swan, with my R2 eyepiece!

 

Black Swan.jpg

 

Allan


Edited by AllanDystrup, 06 August 2016 - 08:19 AM.

  • sparrowhawk and Sasa like this

#97 AllanDystrup

AllanDystrup

    Apollo

  • *****
  • topic starter
  • Posts: 1408
  • Joined: 27 Sep 2012
  • Loc: Denmark

Posted 07 August 2016 - 10:17 AM

M17, The (White) Swan

Diffuse Nebula in Sagittarius.

 

 

   It’s early morning (00:30 local DST) in the start of August, as I contimue my sweep of the inner Sagittarius arm for Messier objects; This morning I have managed to observe and draw the open clusters M11 and M26 (SE of Beta resp. Delta Scuti), plus M18 (SW of Gamma Scuti).

    
     Shifting now M18 to the lower part of the 2° FOV of my ATC K-40 mm finder eyepiece, I get the nebulosity of M17 in the upper part, just 1° N of M18. If the area around
Rho Virginis is the hotspot for deep sky Messier galaxies, then surely the area around the M24 Small Star Cloud in Sagittarius must be the hotspot for Messiers in our own galaxy, -- star clusters and nebulae galore!

  

     In my 10x56 Bino, M17 is seen as a small band of light, and at 24x in the K-40 eyepiece, is shows up as a nebulous bar, with a hook to the W. 

  
     For optimal resolution in my 80mm refractor, I switch to the R2 ccd/lcd in order to make a drawing of the central 20’ region of the nebula. The glowing gas now displays a complex pattern of several brighter clouds shining with a faint rosy hue from hydrogen excited by the radiation of embedded stellar points. The nebula clouds are separated by darker lanes and bays of dust and reduced gas concentration. -- Wonderful!

 

M17-BLACK-CropS.jpg

 

Allan


Edited by AllanDystrup, 08 August 2016 - 07:19 AM.

  • sparrowhawk, mdowns and Sasa like this

#98 AllanDystrup

AllanDystrup

    Apollo

  • *****
  • topic starter
  • Posts: 1408
  • Joined: 27 Sep 2012
  • Loc: Denmark

Posted 13 August 2016 - 04:41 AM


M29, Open Cluster  in Cygnus (NGC 6913)

The Little Pleiades  (’Llama’)

 

this is a Messier observation from almost a year ago, -- thought I'd post it now, for completeness...

 

 

     The transition from daylight saving  to astronomical time happened last midnight, October 24/25 2015, and so it is already getting dark this early evening, 19:00 loc. time. The 13day moon (95% illum.) is however climbing in the SE, embedded in a high, icy cirrostratus  haze, complete with fragments of a lunar halo – not a good night for DSO ...

    

     In spite of the challenging transparency and seeing (Lim.Mag. ~ 4m), I decide to start my sketch of the open cluster M29 in Cygnus. Aiming my red dot at the central star in the Northern Cross, I get Sadr (Gamma CYG) in the 8° FOV of my 6x30 finder, together with the surrounding, irregular circle of stars, that I recognize as ”the heart of the Swan”.

    

     Sadr and the Swan’s heart are now also just contained in the 1.7° FOV @ 24x mag of my telescope with K-40mm wide field eyepiece + 1.7GPC. Shifting the FOV now 1° to the S (ie. close to 2° South of Sadr), i get a small (ca 5’ wide) box shaped asterism in the center of the view: M29.

    

I have to turn up the magnification to 166x @ 15’ FOV to properly frame the box asterism of M29 (using my CZJ O-25mm EP with 6.5x stacked FFC+GPC barlowing). The brightest (~9m)  eight stars of the cluster now fill the central view – the outline reminds me of a standing llama – a long neck, two legs and a short, stubby tail. I can’t detect any fainter stars in the cluster in the current observing conditions, so I will have to return to M29 under darker and clearer skies!

    

M29-Black-Crop.jpg

    

 

Allan

    

 

PS:   Some notes to explain the sparse star field around The Little Pleiades...
 

M29/ NGC 6913  is a close (3.7 KLY), very young (~5 Myr) and tight (10’) open cluster containing ca. 230 stars, including many (~75% ) bright type B and A stars. Of the dozen stars >10m, the 8 brightest are early B0-1 blue hot luminous (160 KSun) supergiants forming a trapetzoid, Pleiades like asterism, that reminds me of a Llama.

    

M29 is located in the OB1 association in the outskirts of the Cygnus X region, a ~10° complex of actively star forming molecular clouds and young clusters around Gamma CYG.  M29 is still embedded in a thick dust cloud, that blocks 95% of the light as seen from Earth (a 3.5m luminosity reduction!).


Edited by AllanDystrup, 13 August 2016 - 04:52 AM.

  • Sasa likes this

#99 AllanDystrup

AllanDystrup

    Apollo

  • *****
  • topic starter
  • Posts: 1408
  • Joined: 27 Sep 2012
  • Loc: Denmark

Posted 18 August 2016 - 03:28 AM

M101
Pinwheel Galaxy in Ursa Major

 

   It’s a bright, moonlit midnight (local DST) in mid August, just at the end of astronomical twilight. There’s a high cirrostratus haze with a ring around the 13dy (93%) moon hanging at 17° altitude in Capricorn, and a few bands of lower, drifting cirrus clouds. Transparency is down at 3/7 and seeing is also around medium 5/10, so we are in a Bortle red zone in my suburban backyard (SQM 17.7 / NELM 4.8m). I am never the less out under the stars, accompanied by a family of hedgehogs, that with loud grunts are rumaging around on our terasse between the herbs and flowerpots. What can I possibly see of Messier objects tonight, with my 80mm refractor?

    

     I settle on M101, the third-largest Messier-galaxy by appearance in the sky. I lay out the star hop with my 10×56 Zeiss bino : from Zet UMa (Alcor/Mizar) -> ca. 1° W to a chain of four ~5.5m stars (81,83,84 & 86 UMa) -> leading 3° SE to a ”kite” asterism of 7-8m stars. Just ½° NW off the tip of the ”kite” is the position of M101, -- though I can’t spot it tonight in the bino (as it is possible under better conditions).

    

     Switching to the view in my ATC K-40mm finder eyepiece (24x @ 1.8°), I do now glimpse the faint nebulous glow of M101, but I’m not able to extract any details of the galaxy structure tonight - apart from a diffuse pale patch with an oval outline - even using higher magnification and averted vision.

    

     Clicking to the R2 ccd/lcd immediately allows me to recognize a starlike core in a brighter E-W oriented nucleus, with 3 major arms sprawling out from the center. I spend the next hour sketching the features of M101, as I am able to observe them mainly using the R2 live video stream : the small central area, the 3-spoked ”pinwheel” spiral pattern with darker dust segments in between and branching out towards the S, -- and even a couple of brighter star clouds in the arms (that I later identify as NGC 5461 and NGC 5447 starburst H II  nebula regions).

 

M101.png

 

 

     I look forward to observe M101 later, under better conditions, as I feel it should be possible to extract even more information from the view, than was possible tonight.

 

Allan

 

    

 


  • sparrowhawk and Sasa like this

#100 AllanDystrup

AllanDystrup

    Apollo

  • *****
  • topic starter
  • Posts: 1408
  • Joined: 27 Sep 2012
  • Loc: Denmark

Posted 21 August 2016 - 03:55 AM

M81 (NGC3031) M82(NGC3034)

 

Obs-1:  
Time: 2016-08-15/16, 22:20 – 00:20 UT,  Loc.:56N 12E Denmark, Alleroed, Setup: 1.5xGPC + CZJ O-25mm; R2 ccd/lcd
Transp.: 3/7 (high haze and banks of cirrus, 12dy 93% Moon @10° Alt in Sgr), Seeing: 7/10, Bortle: Red (SQM 17.6, NELM 4.8m)

 

    It is just past midnight, local time, in early August. There’s a thin high haze with a few passing bands of high cirrus and a 93% Moon at ~10° altitude to the S in Sagittarius. NELM is only 4.8m, so pressing on with the Messiers in the southern Milky Way (as planned) is not a good idea. Instead I decide to aim my 80mm refrector N, at the pair of Boode’s (M81) and the Cigar (M 82) galaxies @ ~35° altitude in Ursa Major.

 

     The star hop is easy: following the line from Nu through 23 UMa, and extending it the same distance (~4° NW) gets me to the triangle of Rho and Sig 1-2 UMa. A line through Sig 1-2 extended 3° NE leads to another star triangle, including the 4.5m 24 UMa. The galaxy pair M81/2 is found just 2° W of this triangle (corresponding nicely to the 1.7° FOV of my K-40mm EP @ 24x). M81 can just be glimpsed in my 10x56 bino.

 

     M81 (Bode’s Galaxy) shows up immediately in my finder eyepiece (24x @ 1.8° FOV) as an obvious oval nebulosity, while M82 (The Cigar Galaxy) is harder to spot in this wide field view. I click up the magnification using my CZJ O-25mm  for 38x @ 1° FOV; This nicely frames the pair of galaxies with the large bright oval of the face-on M81 elongated in a SSE-NNW direction to the south, and the considerably fainter light streak of the edge-on M82 now revealing itself as a narrow sliver of nebulosity elongated SSW-NNE to the north in the field.

 

     At closer study, the oval of M81 shows a gradual increase in brightness to a denser core area, with a not quite stellar core, while M82 remains featureless, apart from a slightly brighter central bar. I can not see the two bright (~9m) double stars to the SW of the core in M81.

 

M81-M82-WHITE-S.jpg

 


  • sparrowhawk and Sasa like this


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics





Also tagged with one or more of these keywords: beginner, classic, dso, observing report, observing, refractor



Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics