Category: Deepsky log

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I suddenly remembered an article I read in Zenit, a Dutch astronomy magazine. There I read an article on observing objects in Cygnus with some wonderful sketches from Fred Hissink, a very experienced deep sky observer from the Netherlands. He had observed (and made a sketch) of NGC 6888, the Crescent Nebula. He used an 80mm Megrez 80II ED and an OIII filter. If he could observe the Crescent nebula with an 80mm, the Veil Nebula, also known as Cygnus Loop or Cirrus Nebula, shouldn’t be a problem for my 85mm Zeiss. I got out the 32mm Televue Plossl and the Lumicon OIII filter, scanned the area around 52 Cygnus and there it was, the Veil nebula. The eastern part of the Veil, NGC 6992-95, was clearly with direct vision, thanks to the OIII. The western part, NGC 6960, which is situated around a bright star, Cygnus 52, took a little longer to detect. After barely suspecting it at first sight, I could detect a small part of the nebulosity using averted vision and adding a little movement to the small refractor. If the western part would have been visible with direct vision, the whole Cygnus loop would have fitted into the 3.2-degree field of view nicely. The Cygnus loop has a diameter of 6 full Moons.

As I mentioned earlier, the whole nebulosity is called Cygnus Loop, Cirrus Nebula or Veil Nebula. To add a little to the confusion, according to Stephen James O’Meara, the eastern segment, consisting of NGC 6992-95 (and IC 1340), is also known as the Network Nebula, the western segment as the Filamentary Nebula. Anyway, whatever the name, it is a beautiful object and I can’t wait for my new 12-inch dob to arrive and have a look at the Veil! I can only say get out there and have a good look at this celestial treasure. For me, visual observing and the aesthetic beauty of all the different objects is the main reason why I’m into amateur astronomy, and the Veil is one of my favorites. Even under light polluted skies this wonderful nebula can be seen even with a small telescope and the right filter.

Below you find a finder chart and a more detailed chart that should give you an idea what the size of the object is in a 3-degree field of view (like my Zeiss with the 32mm plossl). Click on the images to enlarge. Both images have been made with SkyTools2 from CapellaSoft.










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However, the biggest surprise was still to come. As it grew darker, we saw that the sky was much clearer, more transparent, than the night before. Around 23.00hrs we detected the outline of the Teapot (Sagittarius), and a good part of Scorpius was also visible. In the northeast, Capella was already above the horizon, which we didn’t see until 00.15hrs the night before! I started to get really excited, and got the 85mm Zeiss with the 20-60 zoom-eyepiece out, and mounted it on the Manfrotto photo-tripod. Leo had his Sky-mirror with the 15x80 Vixen big binocular mounted. And what did we locate in Sagittarius with these small instruments under these “mediocre” light conditions in the middle of July? Well, it was amazing to be honest. Without too much trouble we spotted M28, M22, M25, M24, M18, M17, M16, M8, M20 and M21. (see the map below, click to enlarge). I couldn’t believe my eyes. Even the nebulosity of M8, M16 and M17 was easy to see, without the use of filters!



Image created with SkyTools 2 by CapellaSoft


On Friday night Sagittarius had been completely lost in the haze, and now there they where, a whole bunch of celestial treasures to be seen with 80mm binoculars and an 85mm birding-scope. We only used some red LED's, a German star-atlas and Sue French’s “Celestial Sampler”, to locate the objects. Oh, by the way, we also used the streetlights on the horizon as points of orientation, and the fully lit church tower in the distance also came in handy for reading the time

This proved to me that air pollution is much more an issue for amateur astronomers than light pollution. I had seen all the Messier object in Sagittarius on a star party in Austria last year, but I never had seen them all from my own hometown. Incredible! Anyway, what I also liked very much about the site last night was the 360-degree horizon. Around 00.00 hours local time we where in for another wonderful sight. The Moon came up over the horizon, and I mean really over the horizon. It was the first time ever for me to see the moon touching the skyline, no haze, no clouds, just a beautiful yellow-orange Moon, and on top of that, a set of big rotating wind turbines where visible as big moving silhouettes against the Moon.

Around 02.00 hours we ended our observing session with a few of our all time favorites, M 27, the double cluster in Perseus, the Coathanger, M 31 and Albireo. Astronomy in the suburbs can still be very rewarding.
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M 42 and M 43
I took of with the Orion nebula (M42). What struck me was the fact that this nebula was easier to detect and better “visible” in my 85mm Zeiss at the lowest possible magnification (16x with the Televue Plossl), than it was in any other instrument I have been using. I checked Roger N. Clark’s book, Visual Astronomy of the Deepsky, and found out that the ODM (Optimum Detection Magnification) for this nebula is about 14x when using a 4-inch instrument under dark skies. My TAL 200K is an 8-inch and M 42’s ODM for this instrument is 27x. The lowest possible magnification on my 8-inch is 62.5x and on the Zeiss I get 16x with the same eyepiece, a 32mm Televue Plossl. In other words, the 3.3-inch Zeiss comes much closer to the ODM than the 8-inch TAL. I don’t know for sure, but maybe that’s why M 42 is best in the Zeiss. M 43 was also visible in the Zeiss using just a little averted vision. In the 8-inch 200K M 43 was not more apparent then in the 3.3- inch Zeiss.

Anyway, after studying M 42 and M43 in the 85mm Zeiss, I switched to the TAL 200K for some medium to high power views of the Trapezium. I was lucky tonight! Despite the mediocre seeing conditions, for the first time ever I immediately detected the 5th Trapezium star (at 166x with the 12mm Lanthanum), the so-called E-component, from my own light polluted backyard. I have already seen the E and F component two years ago from a dark sky site, but never from my own backyard. The central area of the Orion Nebula normally takes very high magnifications well, but tonight 222x (7mm Vixen Lanthanum) was the maximum for the Trapezium area. Higher magnifications only blurred the view.

Eskimo Nebula (NGC 2392)
The Eskimo nebula, the brightest planetary in the winter night sky, looked awesome tonight. At the lowest magnification (62.5x) it was clearly visible as a fuzzy ball of light with averted vision. With direct vision the nebula disappeared, but the 10th magnitude central star popped into view, exactly the same effect as with the Blinking Planetary (NGC 6826) in Cygnus. At 400x (this nebula did allowed high magnification tonight!) it was clearly visible that the nebula consists of a brighter inner circle and a slightly darker and fuzzier outer circle of nebulosity. This is a very rewarding object to observe. I tried all filters and magnifications available. I noticed that the OIII filter has its limitations on my 8-inch with high magnifications. Above 166x (12mm eyepiece) the OIII makes the view to dark. I can observe much more detail at high magnifications without the OIII. At 200x I found the overall image I got at its best. I did not detect the dark ring that separates the brighter inner part from the somewhat dimmer outer ring. I have not detected “the eyes” of the Eskimo.

NGC 2903, M65 and M66
Later that night I decided to have a go at some galaxies in Leo, NGC 2903, M65 and M66. These three more or less bright galaxies in Leo stayed almost completely “invisible” tonight. I could detect the brighter core of NGC 2903, but that was all there was to see. M 65 / M 66 stayed invisible. Not a good night for galaxies, even not for the few brighter ones I sometimes can observe from my backyard.

Saturn and M 44
As time went by, the seeing became worse and worse. Around 23.00 hours UT I aimed the 200K on Saturn. High magnifications proved to be completely useless. It only blurred the view of Saturn. I decided to have a look through the 85mm Zeiss, and at 30x the view was simply wonderful! Saturn and M 44 filled the field of view almost completely. M 44 is a real object for binoculars and rich field telescopes. When it teams up with one of the planets, it always looks spectacular! This was the highlight for me tonight. The stars looked just like sparkling diamonds, and together with the bright Saturn the overall view was simply awesome.



Image from Skytools 2 by CapellaSoft (click to enlargr)


Castor, Iota Cancri, Alcor and Mizar, Sirius and Polaris
I ended my observing session with a few beautiful (double) stars. Castor at 133x showed only the AB pair as two bright white stars. At the time I was observing Castor I didn’t know that there is a C component, a magnitude 8.8 red dwarf, about 73” from the A component. I will try to observe this faint companion next time.

Iota-1 Cancri is one of my favorite doubles. Even in the 85mm Zeiss at 60 to 70x the two components are visible as a golden a blue pair, almost as beautiful and striking as Albireo. This double should be on everyone’s observing list, just like Alcor and Mizar. This naked eye-duo looks great through almost every instrument. I simply enjoyed the view through the small refractor for a few minutes, before I pointed the Zeiss at Sirius, the brightest star around. Now I could see the quality of this small instrument. Sirius looked just like a bright white star. No colors visible around the edges and no Fringe Killer needed!

Last but not least was Polaris. Believe it or not, after all these years, this was the first time I looked at Polaris with my telescope, and I found this double surprisingly easy to see. Polaris has two components A and B. A is a magnitude 2.0 yellowish star and the much fainter B (magnitude 8.2) can be found at a position angle of 218 degrees and at a distance of 18.4”.

At 00.30hrs UT I decided it was time to pack up, after four and a half hours of freezing cold. Around 2 o’clock AM local time I sat indoors, warmed by the heater, enjoying a glass of malt whiskey (no ice) and dreaming about the beautiful objects I had seen tonight. These are the nights that keep me in this wonderful hobby……..




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The Moon
We started with the Moon. The view through the TAL 250K and bino-viewer was simply stunning. The first thing that caught our attention was the alpine valley area. The view of the Alps and especially the shadows they casted, were awesome. They looked like a row of teeth on the lunar surface. Then there was in the same field of view the extremely long, triangular shadow of Mons Piton. To the north-northwest of Piton, the tops of Mons Pico and the mountain just to the south where lit by the Sun while the base and Mare floor where still in the shadows. Just right in front of the Alps some of the Mare ridges where visible.

To the south of the Alps, a part of the northeastern part of the Apennines was already visible, and with the bino-viewer it was as if we observed the mountain chain in 3-D. To the south-southeast of the Apennines, on the edge of Mare Vaporum, was a large rectangular area visible. It looked just like a big landslide to us. With the bino-viewer, Rima Hyginus with the crater in the middle, was again a wonderful sight. To the west of Hyginus, part of the Rimae Triesnecker complex was visible.

On the southern hemisphere, the most interesting feature was the group a group of four craters, Ptolemaeus with to its east Albategnius and to its south Alphonsus and Arzachel. On the floor of Alphonsus, a dark patch could be seen on the western rim of the crater floor. This is probably the result of some volcanic outfall.

We observed the Moon for quite some time, and we concluded that with the bino-viewer the views are simply the best. You see much more detail than with one eye, and observing is not tiring at all. You can observe using both eyes for hours on end. What also surprised us was that you could see Rima Hyginus with the 85mm Zeiss Diascope, with the zoom-eyepiece at maximum zoom (60x). The quality of this small birding-scope is very good.



Image shot with the Coolpix 4500, Zeiss Diascope and Zeiss zoom
eyepiece a few hours before the actual observing session


Saturn
We only had a short look at Saturn. The seeing was deteriorating quickly (a lot of moisture in the air), and high magnifications were useless. However, the Cassini division was very clear, and we could also see a dark band across the surface of Saturn. We are still discussing about this dark band, was it the shadow of the rings, or a dark zone in the clouds of Saturn?

Deepsky
We started with M 35 in Gemini. This large open cluster looked best in the 8-inch Vixen, because of the wide field of view (f/4 800mm) that you get with this instrument. From there we went to Orion. M 42 was unbelievable in the bino-viewer. Of course you can only see a small part of this nebula in the TAL 250K, using the bino-viewer, but the views were great, even without the nebula filters. The area around the trapezium is one big complex of nebulosity, which you can observe again and again, and you always will see new details. We did not detect the E or F component of the trapezium group (theta Orionis). With the Zeiss Diascope at 60x, the Orion Nebula looked like a big bird flying through the skies with its wings spread. It was amazing to see how far out both nebulous wings spread out from the centre. Again a very pretty sight. M 43 was also visible in the 85mm refractor, using a little averted vision.

We also looked for the running man (dark area between NGC 1973, 1975 and 1977) but we did not detect any nebulosity in the area. The same goes for the Horsehead nebula (IC434) and M 78. They also stayed invisible, even with the nebula filters we used.

Next on the list was M 44 (Praesepe) in Cancer. This is really a wide open cluster, and it fitted niceley in the 8-inch f/4 Vixen and the 85mm Zeiss. The best view however was with the 15x80 binoculars. Saturn and M 44 nearly fitted into the same field of view! From M 44 we moved to Gemini again. This time for a planetary nebula, the Eskimo Nebula (NGC 2392). It was very easy to spot at higher magnification (fuzzy appearence), but at low powers it just looked like a star. With the bino-viewer and the two Zeiss eyepieces, you could see a grayish, equally bright centre and a fuzzy outer ring around it (probably the Eskimo’s fur-lined hood). We did not see “the eskimos eyes” which you see on the many photographs. From there we hopped south into Monoceros to have a look at the “Christmas Tree”, NGC 2264. It didn’t fit into the TAL’s field of view but with the 8-ich Vixen, it looked just fine, a small Christmas tree. We also looked for Hubble’s variable nebula, but it was “invisible”. Hubble’s variable nebula (NGC 2261) is very intriguing object. Sometimes you simply just see it, and sometimes it is completely invisible.

Finally, we observed a few double stars with the Zeiss. Cor Caroli and Alcor/Mizar are still two of my favorites after all these years. The Zeiss shows them really well, esthetically a beautiful sight. Around three o clock we packed up after six hours of observing. After two months of cloudy nights, last night was a real treat! « Collapse

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M 39 (image from SkyTools2 by CapellaSoft)


2. M 103 (NGC 581)
This open cluster in Cassiopeia is often overlooked because of the fact that it is very small and therefore not “spectacular”. M 103 can be located very easy. First find Ruchbah (Delta Cassiopeiae). Go 1 degree to the east-northeast. There you will find M 103. Until now I did not resolve this small open cluster completely with my 15x80 binoculars, but I definitely detected some stars superimposed on a somewhat hazy background of M 103. In the 8-inch Klevztov at 133x Messier 103 is resolved almost completely. M 103 has a diameter of 6’ and a visual magnitude of 7.4. With 25 to 30 stars ranging from magnitude 8 to 12, the triangular shape of M 103 definitely makes it look like another Christmas tree in the night sky. Three of the cluster’s brightest stars mark the tips of the triangle. When I increase the magnification I gradually detect more and more, fainter stars. The star at the "top" of the Christmas tree is yellow white. The star at the southeast apex is bright white. Others report a 9th magnitude red star at the centre of the cluster. Until now I haven’t “seen” it but maybe my telescopes aperture is to small to detect colours of 9th magnitude stars. Anyway, M 103 is a lovely small open cluster, so be sure to visit this celestial Christmas tree with your telescope the next time your in the Cassiopeia area.



M 103 (image from SkyTools2 by CapellaSoft)


3. NGC 2264 (The Christmas Tree Cluster)
The last of the three Christmas trees, NGC 2264, can be found in Monoceros. During this time of the year you have to wait until three o’clock in the morning to see the constellation culminate high in the south. NGC 2264 (nicknamed the Christmas Tree Cluster) is very easy to find. From 31 Xi Geminorum go south-southwest for about 3 degrees where you will find the 5th magnitude 15 Monocerotis, the brightest star of NGC 2264. In my 15x80 binoculars I already see almost all the stars that mark the outline of this heavenly Christmas tree. NGC 2264 is a large, bright open cluster with a diameter of 20’ and a visual magnitude of 3.9. In my 8-inch Klevtzov at 62x I see about 20 to 30 stars. When increasing the magnification I detect more and more fainter stars. By the way, in my Klevtzov-Cassegrain, the Christmas tree stands upside-down.



NGC 2264 (image from SkyTools2 by CapellaSoft)


Well, here ends my journey to the three celestial Christmas trees. I enjoyed it very much and I can only recommend these three open clusters wholeheartedly. Happy “tree” spotting!
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To warm up for a long night of observing I started with one of my favourite doubles, Eta Cassiopeiae, also known as Struve 60. The difference in colour and magnitude is just wonderful. The A component is a golden magnitude 3.4 star. At a position angle of 317º lies it's companion, a yellow-orange magnitude 7.5 star. The separation between both stars is about 12", an easy split even at lower magnifications.

After half an hour my eyes where adapted to the dark, and it was time to visit some open clusters in Cassiopeia, M 103 which a have observed a few times before, and a few "new" ones on my list, Trumpler 1, NGC 663 and NGC 654. As you can see on the map below, the four open clusters are all situated in the area between Delta and Epsilon Cassiopeiae. You can enlarge the map by clicking on the image.



Map from SkyTools 2 by CapellaSoft


M 103 (01h33.2m +60°42')
This small open cluster looks like a small triangle or Christmas tree. It is only 6' wide and its magnitude lies between 7 and 8. At a magnification of 133 I counted about 20 stars, at 200x about 30. What is clearly visible is that two of its brightest stars can be found at two of the apexes of the triangle. The star at the "top" of the Christmas tree is yellow white. The star at the southeast apex is bright white. Right at the centre of the cluster I detect a pair of stars that seem to be yellow and blue, but I'm not 100% sure about this one. Others report a 9th magnitude red star at the centre. I cannot find it but maybe my telescopes aperture is to small to detect colours of 9th magnitude stars.

Trumpler 1
Now this little gem really surprised me, and I immediately recognized it. I had seen it before, when looking for other objects in the area, but I failed to identify it. I had to use a little averted vision, but I definitely saw two rows of stars, running more or less parallel to each other in NW-SE direction. One row holds tree stars that are very easy to see from my backyard. Using a little averted vision, a fourth star comes into view, while the other row also shows itself with three stars. With averted vision at lest 10 other stars pop into view. Trumpler 1 has a diameter of 4.5' and its visual magnitude is 8.1. It is a detached, strongly concentrated cluster with a large range in brightness and poor richness in stars. Be sure to visit this little gem the next time your in the M 103 area!

NGC 663
My next stop was NGC 663. This 16' wide, magnitude 7.1 open cluster looks more or less elongated, with a beautiful double to the east of it's brightest star. At a magnification of 133x the cluster almost fills the field of view. The best view however as at 100x (20mm Vixen Lanthanum). I counted more than 30 stars, when using averted vision. It's brightest star shines at magnitude 8.4. This is the first time I observed NGC 663, but it won't be the last. I wasn't in the mood for sketching tonight so I will save that for the next time. The image below comes very close to what I saw through the eyepiece. Click on the image to enlarge. The limiting magnitude is 12, north is up and west is to the left.



Image from SkyTools 2 by CapellaSoft


NGC 654
About 0.75 degrees to the north-northwest of NGC 663 lies my last open cluster for tonight, NGC 654. This open cluster has a diameter of 5' and its visual magnitude is 6.5.
NGC 654 is a very delicate, small open cluster. It has a lot of stars that seem to be of an equal magnitude. At a magnification of 166x, the stars keep popping in and out of view, but when looking a bit longer using some averted vision I count 15 to 20 stars. At the south-south-eastern edge of the cluster lies a bright, magnitude 7 or 8 star. At 133x the cluster is at its best. It looks like somebody spilt some grains of salt over a black tablecloth. A wonderful view.

About 23.00 UT it was time for a coffee break, but first I wanted to give my two light-pollution filters a little test. After trying them on NGC 654, NGC 663 and Trumpler 1 the conclusion was very simple. The Baader Skyglow left the whole view intact, but didn't make the sky look any darker. The Lumicon deepsky filter definitely darkened the background but......... killed a lot of the faint stars in all three clusters, and coloured the brighter ones. Conclusion: visually these broadband filters are of no use for observing open clusters.


PART 2: DOUBLE STARS, MARS AND M77
At 0.30hrs UT I started with the second part of my observing night with a few double stars in Aries. If you look about 10º south of Triangulum you will see three stars in a more or less crooked row. These are Alpha, Beta and Gamma Arietis, the three brightest stars in the constellation of Aries. I included the map below to give you an idea where to find Aries. Note the position of M 45, the Pleiades. It might help you to locate the three bright stars. I selected four doubles for observing tonight: 1, Gamma, Lambda and Epsilon Arietis.



Map from SkyTools 2 by CapellaSoft


Gamma Arietis
I started with the brightest of the four doubles, Gamma Arietis. This is a magnitude 4.8 star, that I can see with my naked eyes from my backyard. With a small viewfinder it is easy to spot. What I immediately noticed that there seems to be no difference in colour or magnitude between the two components. Both shine in a white light and after verifying I found out that both stars are of exactly the same magnitude, 4.8. They are separated about 7.8" and the B component lies at a position angle of 0º. At 100x I really enjoyed these two celestial gems for a few minutes. Double stars are fun, even under light polluted skies!

1 Arietis
This is a close pair of stars, only 2.8" apart from each other. I could split them at 80x (hint) and 100x (sure), but the best view was at 166x. The brighter, magnitude 6.2 A component looks yellow while the magnitude 7.2 B component, lying at a position angle of 166º, looks white. 1 Arietis can be found 1.75º north-northwest of Beta Arietis. A very nice couple!

Lambda Arietis
To locate Lambda Arietis, just go northeast for a little more than 2º. Lambda is a very wide double, separated by 37.4". The A component is yellowish magnitude 4.9 star. The bluish magnitude 7.7 B component lies at a position angle of 46º. This double was at its best with the lowest possible magnification of 62x.

Epsilon Arietis
This double is a very though one. They are almost of equal magnitude (5.2 and 5.5) but only 1.5" apart from each other. Maybe the seeing had deteriorated in the last hour, because I was able to split 1 Arietis, which components lie 2.8" apart, but I was unable to split Epsilon, even at 400x. As you can see on the map above, Epsilon lies almost halfway between Aries and M45. I will have to wait for a more stable atmosphere before trying to split Epsilon Arietis.

Mars
Around 1.45 UT Mars was already high in the southeastern sky, together with the Pleiades. Because the seeing was getting worse I first didn't want to point the telescope at Mars, but on second thought I decided to give it a try. I was surprised! At 166x I definitely detected some darker areas on the rust coloured surface, and both poles looked white. Because Mars was jumping up and down due to the bad seeing, higher magnifications where not possible.

M 77
Around 2.15 UT (I was getting really tired) I decided to go for one last object, M 77 in Cetus. I had never seen it but tonight it was relatively high in the sky, and should be easy to spot. I could see the 4 or 5 stars that mark the tail of Cetus, so I had a go at it. As you can see on the image below, M 77 can be found 3 to 3.5 degrees south of Gamma Ceti, the second brightest star in the tail of Cetus. I didn't expect to see anything at lowest magnification, but I was in for a surprise again. I think that after M 31 this is the easiest galaxy for me to see. Using direct vision, it has a very bright core at 62x, even as bright as a star (9th magnitude) that lies to the east southeast of the galaxy. At 166x, using averted vision, the galaxy almost doubles in size, a round glowing disk with a very bright and large core. A great object to end my long night of observing at 2.40 UT. I can only come to the conclusion that even in a suburban area you can enjoy a long night of deepsky observing. You only have to choose the right objects!

Clear skies!



Map from SkyTools 2 by CapellaSoft
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Fecunditatis look much darker than Mare Imbrium. Between Mare Frigoris and Mare Imbrium the dark lava flooded floor of the crater Plato really stands out from its surroundings. The three very bright (young) craters Tycho, Copernicus and Aristarchus really jump out at you. The crater rays of Tycho and Copernicus are a wonderful sight, even through 7x50's.

Later that night I observed a few objects in Cygnus with the Vixen 7x50. While centring the field of view on Gamma Cygni, the star that marks the "body" of the Swan, M 29 can be seen in the same field of view very easy. It looks like a small smudge of light, about 2 degrees south of Gamma Cygni.

From there I went to Omicron 1 and 2 Cygni, my favourite group of colored stars in Cygnus. Omicron 1 and 2 are both very orange colored 4th magnitude stars, that can be found 4.5 degrees southwest of Deneb (Alpha Cygni). Omicron 1 is also a visual triple. It stands together in the night sky with a very blue star (magnitude 5) about 5.5' to the northwest of the orange Omicron 1. They form a very beautiful visual pair of stars with brilliant colors. The third star of Omicron 1 is a magnitude 6.9 star about 2' to the south of the orange star.

Next on the list was the narrow double star (for binoculars) 61 Cygni. Although the two almost equally bright components are only 29" apart, they are an easy split in 7x50 binoculars, especially when the binoculars are mounted on a mirror mount. The two stars look bright orange to me.

I also visited M 39 with the 7x50. The triangle of stars is very easy to find. Just go from Deneb about 9 degrees to the east-northeast and you will come across a bright triangle of stars. This is M 39. Because the clusters stars are scattered over an area of 30' they looked better in the 7 x 50 than in the telescope.

At 23.00 hrs UT we had a tea break.


TAL 250K (M 13, the Blinking Planetary, M 27 and M 57)
After half an hour we continued with the TAL 250K. It was still around 17 degrees Celsius outside, but the air was very dry. Nothing dewed and the books that where lying around felt dry. Later that night when I got home I checked my weather station. Humidity was only 27 percent outside.

We looked at several objects both with and without the binoviewer, and boy, this piece of equipment from Baader really makes a difference with some of the objects observed. I was shocked by the different appearance of M13. In the middle of June, when the nights are very short and it doesn't get really dark, M 13 looks just like a smudge of light with very few stars resolved when I look with my 8 inch TAL 200K. With the 10-inch TAL 250K there are significantly more stars resolved, but when you put in the binoviewer, the whole cluster just stands there, with chains of stars running from the centre outwards. I wonder how M 13 will look around the end of august, when it gets a lot darker. Anyway, on this globular the binoviewer made a real difference!

The next object to visit was NGC 6826, the Blinking Planetary. On the finder chart below (click to enlarge) you can see where to find NGC 6826. Start at Sadr (Gamma Cygni) at the centre of the Cygnus. From there go about 9 degrees northwest to δ (Delta) Cygni. From delta go north to θ (Theta) Cygni, a magnitude 4.5 star. The blinking planetary lies a little less then 1.5 degrees to the east.




Image from SkyTools 2 by CapellaSoft (Click to enlarge)



We viewed the planetary at a magnification of 200x and used no filters. We immediately saw why NGC 6826 is called the blinking planetary. When you look at it with averted vision you see a nice round and bright planetary nebula without a central star. When you look at it directly, the nebula vanishes completely and the central star becomes visible. Just by moving your eye a little it pops in and out of view. A truly wonderful object!

Later that night we observed two other planetary nebulas, M 27 in Vulpecala and M 57 in Lyra. Here the different reaction to nebula filters showed really well. While M 27 got much more contrast with the OIII filter, the same filter did nothing with M 57. M 27 looked really big and M 57 was also very different from what I am used to see in my 8-inch Klevtzov. The centre of M 57 is not open but looks a little hazy white.

At 01.00 hours UT (3.00 local time) we packed up, satisfied with the first test of the TAL 250K equipped with the binoviewer. I noticed that for some objects the binoviewer showed more detail (like M 13, the Moon), for others it didn't,. However the viewing with two eyes is much more comfortable than with only one eye. It is definitely less tiring.

At 3.30 local time I dropped into bed, while the first birds where already starting their morning concert.
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