June 18-19, 2009
On June 18th, 2009 I was able to grab a session in my backyard. I wasn't feeling very well that evening, as I was still recovering from being glutened (I'm a celiac so no products with gluten in). I began tonight by just cooling down and setting up and then went through the following objects:
Seeing 8/10 Air is calm and upper winds are not an issue
I started in Ophiuchus at 11:00p.m. on June 17th, 2008. The next three objects were observed in an XT10 using a 13mm Stratus eye piece at 92x.
M12 Globular Cluster
11:00p.m. The globular is large and mottled. Appears to have a triangluar shape though the central core is not heavily seen; it is hinted at with averted vision. At 92x in the 13mm Stratus the entire cluster is easily visible and gives great detail. I can resolve the entire cluster and individual stars are easily visible. The core is about 20% of the halo and slightly brighter at times when transparency improves. There are four chain of stars evident to me. This is a wonderful globular to spend time with enjoying the details found within it.
M10 Globular Cluster
11:30p.m. This globular is round in shape, and the core is diffused and loose and makes up about 20% of the entire globular. Mottling was evident in the globular. Beautiful globular that is typical of globulars with a tight inner core and a nice bright halo. Core is equal in brightness in this case to the core. Easy tonight to distinguish some individual stars in the globular. Arms seem to be evident though I am unsure but included them. Another good globular to look at.
M6 Open Cluster in Sagitarrius (Butterfly Cluster) June 18th, 2009
To locate this cluster telrad to Alnast and then go diagonally down to the right and you can't miss it. M7 is right below it. The Butterfly shape is easy to see for me when looking at this cluster. There are several smaller but bright bluish stars near the top of the butterfly and a bright orange/yellowish star in the tail of the butterfly. The bright orange/yellow star is larger than the blue stars that are so clearly visible. This cluster is medium rich in stars and averted vision really helps to bring more of the stars out. Here is an inverted version of my sketch:
M22 Globular Cluster in Sagitarrius
XT10 using 21mm and 13mm Stratus and 5mm Hyperion
To find M22 I used the telrad to get to Kaus Barealis and then go up diagonally to the left and you'll run right into it. In my 21mm Stratus that I use as a finder eyepiece I can see an inverted and upside down L made up by 25 and 24 Sagittarrii which are the vertical parts of the L. A small and tight globular this is a great example where the core is much brighter than the halo of the globular. I estimate it at around 40% of the cluster. The globular is huge and is resolved across all of the globular. Averted vision for me brought out a band of darkness running SW to NE. Good object to view in both the 21mm Stratus, the 13mm Stratus and the 5mm Hyperion. Clear crisp image in all EP's.
I'm not happy with the sketch and will be revisiting this before the middle of August to resketch. I took over an hour and a half to sketch but could tell I was still not feeling good.
June 18, 2009 next evening
M9 Globular Cluster 11:52p.m.
XT10 with 13mm Stratus
I used the telrad to go to Sabik and then over to 3 stars running north-south in a equalateral triangle that is facing east-west. No go down to a double and M9 is down a little bit to the left as I see it in my 13mm Stratus. The core is very bright as is the globular itself with the core being much more brighter than the halo around the globular. As I continue to look I want to resolve a chain of stars that appear to be in the S. to SE and there is some granularity is present, but I had to use averted vision to see it.
XT10; 13mm Stratus
My next object was M107, a globular cluster in the constellation Ophiuchus. This globular is one of the weakest globular that I've seen. I can view a small inner core around 10% or so of the halo. Some stars are resolved in the halo individually. Direct vision shows the core and averted vision ab out 1 moon length of the core and hints at individual stars. My 5mm Hyperion is too much power on this object tonight as transparency is continuing to degrade.
July 15th and 16th, 2009
M20 Trifed Nebula
XT10 and 13mm Stratus and Orion Ultrablock NB Filter
dddThis is an easy item to find and I have viewed it several times in the past. Simply go to the Lagoon Nebula and then look for 4 stars in a trapizoid above it and to the right/west. The bottom star in the finder or binoculars is M20. My observation chart shows how I found it and if I remember I'll include it later. The center star in the southern hub of the Trifed is a double and without a filter a hint of nebulosity shows. Putting in the narrowband filter the nebula jumps out. This is a great example where averted vision allows one to see more though. I can make out the three dark lanes separating the nebula into sections. Dark adapation and averted vision with a narrowband filter is key to this wonderful object.
M17 The Swan Nebula or Omega Nebula
Orion Ultrablock NB Filter
If you start again at the Lagoon Nebula M8, and then up to M21 the Trifed then continue to work your way up. M17 is just above the open cluster M18. M18 is above 3 stars in a horizontal line. These three stars are just above M24, The Star Cloud which is just absolutely gorgeous! I could spend hours sketching in there but I need to improve my sketch a lot more before I tackle that object (as you'll see in my Swan Nebula sketch; I need to redo this one, it looks like a terradactyl). I have to say that outside of M42 right now, the Swan Nebula is perhaps my favorite emission nebula (so far). Without the filter I can make out parts of the nebula but yet again, the narrowband filter really brings this object into clarity, and WOW!!!! It definitely looks like a swan on the surface of the water; or in my opinion perhaps a lune. The breast area of the swan is really bright and condense with the head visible but lightly as is the rear of the swan/lune. The edges are diffused in most places, but look sharp in the NW edge. Some stars are visible on the neck region, but none in the center. I could see no dark lanes tonight but will go back to the Swan in my next session to observe more details.
A narrowband filter on this one is a must!
I have this sketch and am going to a dark site to do this justice. I'll repost it.
M18 Open Cluster
M18 is easy as I just dropped down from M17. This is a tight open cluster that is in a triangle shape. It is a young star cluster at around 30 million years old based on the type of hottest stars in the cluster, spectral type B.
NGC 6210 Planetary Nebula "The Turtle"
13mm Stratus; 5mm Hperion; Orion Ultrablock Narrowband Filter
I now turned my attention to a couple of my favorite DSO's, Planetary Nebula. I'm not sure why I enoy them so much since they signify the death of a star, but in some ways they also signify the birth of new stars by the elements they put out into interstellar medium.
To get to NGC 6210 I used the telrad to jump to Komehporos in Hercules and then to a group of tars that are up and to the left (east in a finderscope, opposite in an EP). On the right hand side of this group of stars is an asterism of a triangle with a double star on top (pointing east in a finderscope, righ in a finder EP in a dob). From the top at the double star, jump across to another double star right across, adn then go to the left in the eyepiece. The Orion Ultrablock Narrowband filter really didn't show much at this time except to confirm it is a planetary nebula by its ball shape versus the pinpoints of the stars in the area. I did most of my observing without the NB filter and moving back and forth between the 5mm Hyperion and the 13mm Stratus. At 92x in the 13mm Stratus the color of the PN was a greenish-blue and was a ball shape. I could detect an inner core (hints with averted vision) and an outer halo. At 200x in the 5mm Hyperion the color remained the same. Of course no central star was apparant due to poor seeing conditions in the atmosphere I could not see the 12th magnitude star (I've seen it listed at 12.7 at one source, and David Knisely has seen it in his 2000 online observation. No luck for me tonight. Perhaps if the sky settles I'll give the central star another try. At 200x the edge is diffused forming a pale halo/circle around an inner core/halo. At 200x I could also make out what I first thought was a similar image to the Saturn PN Nebula, but the inner core was irregular in shape. Upon observing for around twelve to fifteen minutes I was able to make out three irregularities from the inner core. This truly does give it an image of a "turtle."
As a bright planetary nebula it is a fun object to go after and take a look at. Just some fun info on this obect: "At a distance of 4700 light years the apparent size of this nebula translates to an actual diameter of about 0.4 lights years or 25,000 AU. That's about 300 times larger than our solar system if you take its diameter as the mean orbital distance of Pluto." If you understand distances even just in the solar system, the nebula is large in human terms. Very cool.
NGC 6818 Planetary Nebula "Little Gem"
13mm Stratus and 5mm Hyperion; Orion Ultrablock Narrowband Filter
Telrad over to Rho 1 Sagittarri and then jumped to 43 Sagittarii. Then I jumped up to Upsilon Sagittarri, a bright star up and to the left in a finder. I now jump to HIP95755 then over to HIP96536. From HIP 96536 I went to the south and east and there I found NGC6818. Best view at this time was in the 13mm Stratus as conditions were started to worsen. It stuck out easily as a planetary nebula with no filter in the eyepiece. NGC 6818 is green/emerald in color, rounded or circle in shape, with diffusion at the edges and no irregularities at 92x. The NB filter brings out the brightness of the planetary but no further details as it turned it white. 200x did not bring out any further details. This sketch is done at 200x.
Well, that's all. Here's hoping I can get out this week but the monsoons from Mexico have snuck in around a high pressure that is moving east. I wonder if the clear skies of summer will last for more than a week this year?