Archive for December, 2011

Hickson’s in the wind!

Blog Wednesday 28th December 2011

 

Big Andrew Robertson in Norfolk had given me the heads up during a telephone conversation earlier in the day that it was going to be a clear one. The sky cleared in the afternoon to a perfect sky and temperature dropped as daylight leaked away. A delightful waxing Moon decorated the sky to the south with a blazing Venus below in the SSW, Jupiter with a loftier perch in the SE, a lovelier evening scene is hard to imagine. On the negative a stiff breeze had got up and this continued to build as darkness fell and was to prove a telling factor with my nights observing.

As soon as dinner was cleared away I was out and had the observatory open, I synchronised the telescopes and software by sending the mount to Jupiter, even with the cameras at a very fast exposure and refresh rate the planet was like a wasp in a jar!

It had been my attention to work in Taurus, Aries and Pegasus and catch a few more of the tricky Hickson compact galaxy groups. After reviewing this idea I went for HCG 5 in Pisces, a little lower I thought and I was attracted by the fact that the main member was an NGC galaxy so my software should take me there pretty easily. This turned out to be true NGC190 got me straight onto the group, the only problem was the wind shaking the big reflector, I had to reduce the exposure time which meant that I wasn’t going so deep and detail displayed on the monitor would be limited, longer exposures around 20secs that I like to use on faint galaxies such as these would mean just a smeared mess on the monitors. Even with the shorter camera time I had to be patient before I got any decent images on the screen, I f I was happy with it, I froze that frame and sketched the detail, all the 4 group members were readily visible but field stars didn’t show as point light sources making them all look like tiny faint additional galaxies, very frustrating. As it happened I managed to capture the scene pretty accurately as checking with the Palomar image on Aladin the next day proved, a better night and I should have pulled a little structural detail out of the central NGC190a. A nice little cascade of galaxies, see my sketch here

I clearly had to look lower and get the scope further out of the wind, but that could wait I was going indoors for an hour to watch BBC Top Gear with my sons, a real lads thing. I was back out promptly at 21.00ut and continued with HCG 4 low in Cetus, well low for the UK at -21 Dec! The sky there to my south was very poor the Sky Quality meter reading just 18.8 compared with the reading for the HCG5 in Pisces which was 19.5, not good itself. With some hunting around I found the group, my planetarium software doesn’t recognise the Hickson atlas so I have to search by galaxy catalogue identifier if I have one? Or if not by RA & Dec, as my set up is NOT pin point accurate this can take a while, but in a way the difficulty adds to the fun factor for me and overall satisfaction when successful. I did get HCG4 the primary or (a) member being PGC2047 an attractive mag 13.8 barred spiral, in images there is a lot of detail visible in this galaxy, the Palomar image show much to interest so under the right conditions I should see that with ease. The conditions however weren’t right! I did see a central extended bar and structure, an arm projecting on the western edge and heading north, strangely when I checked today there is something going on where I indicated but it is faint compared with much more prominent N-S arms that were invisible to me, apart from that with patience, and by that I mean around 60 mins spent on the observation it is a good one and another from the list. See my sketch here

I exchanged texts and conversations with Andrew Robertson as is usual during observing sessions, we can pretty much guarantee that each other will be out there if conditions are right J

The last search of the night was for HCG 28 in Eridanus, the wind appeared to have eased a little it was now past 22.00, with no identifier member galaxy to search for I was scanning by coordinates, I found a group of galaxies centred on PGC 15061. I returned to my search for HCG 28 which was close by, somewhere! After 15 mins I returned to PGC 15061 and sketched the field, I identified 3 members in total at the time but using Aladin the next morning found one of the stars that I had drawn it was in fact another galaxy making 4, so I smudged the original point star to give it some fuzz ;¬) Aladin etc listed this as a group so I have named it PGC15061 group the member to the NE is not identified as a PGC galaxy by as Ginnis j042512.70-095334.8, I know rolls off the tongue doesn’t it!! See my sketch here

Well that I was it, cloud was coming in from the west, I could see that on my wide field lens and Mintron camera and all observations had been hard one tonight.

Blog Wednesday 28th December 2011

 

Big Andrew Robertson in Norfolk had given me the heads up during a telephone conversation earlier in the day that it was going to be a clear one. The sky cleared in the afternoon to a perfect sky and temperature dropped as daylight leaked away. A delightful waxing Moon decorated the sky to the south with a blazing Venus below in the SSW, Jupiter with a loftier perch in the SE, a lovelier evening scene is hard to imagine. On the negative a stiff breeze had got up and this continued to build as darkness fell and was to prove a telling factor with my nights observing.

As soon as dinner was cleared away I was out and had the observatory open, I synchronised the telescopes and software by sending the mount to Jupiter, even with the cameras at a very fast exposure and refresh rate the planet was like a wasp in a jar!

It had been my attention to work in Taurus, Aries and Pegasus and catch a few more of the tricky Hickson compact galaxy groups. After reviewing this idea I went for HCG 5 in Pisces, a little lower I thought and I was attracted by the fact that the main member was an NGC galaxy so my software should take me there pretty easily. This turned out to be true NGC190 got me straight onto the group, the only problem was the wind shaking the big reflector, I had to reduce the exposure time which meant that I wasn’t going so deep and detail displayed on the monitor would be limited, longer exposures around 20secs that I like to use on faint galaxies such as these would mean just a smeared mess on the monitors. Even with the shorter camera time I had to be patient before I got any decent images on the screen, I f I was happy with it, I froze that frame and sketched the detail, all the 4 group members were readily visible but field stars didn’t show as point light sources making them all look like tiny faint additional galaxies, very frustrating. As it happened I managed to capture the scene pretty accurately as checking with the Palomar image on Aladin the next day proved, a better night and I should have pulled a little structural detail out of the central NGC190a. A nice little cascade of galaxies, see my sketch here

I clearly had to look lower and get the scope further out of the wind, but that could wait I was going indoors for an hour to watch BBC Top Gear with my sons, a real lads thing. I was back out promptly at 21.00ut and continued with HCG 4 low in Cetus, well low for the UK at -21 Dec! The sky there to my south was very poor the Sky Quality meter reading just 18.8 compared with the reading for the HCG5 in Pisces which was 19.5, not good itself. With some hunting around I found the group, my planetarium software doesn’t recognise the Hickson atlas so I have to search by galaxy catalogue identifier if I have one? Or if not by RA & Dec, as my set up is NOT pin point accurate this can take a while, but in a way the difficulty adds to the fun factor for me and overall satisfaction when successful. I did get HCG4 the primary or (a) member being PGC2047 an attractive mag 13.8 barred spiral, in images there is a lot of detail visible in this galaxy, the Palomar image show much to interest so under the right conditions I should see that with ease. The conditions however weren’t right! I did see a central extended bar and structure, an arm projecting on the western edge and heading north, strangely when I checked today there is something going on where I indicated but it is faint compared with much more prominent N-S arms that were invisible to me, apart from that with patience, and by that I mean around 60 mins spent on the observation it is a good one and another from the list. See my sketch here

I exchanged texts and conversations with Andrew Robertson as is usual during observing sessions, we can pretty much guarantee that each other will be out there if conditions are right J

The last search of the night was for HCG 28 in Eridanus, the wind appeared to have eased a little it was now past 22.00, with no identifier member galaxy to search for I was scanning by coordinates, I found a group of galaxies centred on PGC 15061. I returned to my search for HCG 28 which was close by, somewhere! After 15 mins I returned to PGC 15061 and sketched the field, I identified 3 members in total at the time but using Aladin the next morning found one of the stars that I had drawn it was in fact another galaxy making 4, so I smudged the original point star to give it some fuzz ;¬) Aladin etc listed this as a group so I have named it PGC15061 group the member to the NE is not identified as a PGC galaxy by as Ginnis j042512.70-095334.8, I know rolls off the tongue doesn’t it!! See my sketch here

Well that I was it, cloud was coming in from the west, I could see that on my wide field lens and Mintron camera and all observations had been hard one tonight.

More Hickson’s in time for Christmas

Blog Friday Night/Sat morning 23rd/ 24th December 2011

 

If you read this blog regularly you will be quire aware that chasing the Hickson compact galaxy groups (HCG’s) has become quite a preoccupation with me, if not something of a minor obsession.

With work concluding at lunchtime on Friday 23rd I was looking a 10 full days before I was to return, surly there would be some clear windows for observation during this welcome break. The Moon is new on Christmas Eve so the early holidays would be a perfect time for deep sky observing.

I noted that the sky had cleared at 10pm 22.00ut on Friday night so I was straight out into the observatory, the ‘Powermates’ and ‘barlow’ lenses were removed from the telescopes and I was soon hoping to the bright stars of Orion. Very close to gamma Orionis I found HCG34 as listed as ARP327, this is a tiny tumbling cascade of 4 faint galaxies with the brightest NGC1875 at the head of the fall, running through PGC17173, PGC17175 and terminating with PGC17176, see my sketch here.

I now ‘had the flavour’ and moved onto HCG31 again in Orion this time out just below the Hunter shield. Star hoping to p6 Orionis then using the goto to take me to NGC1741A the primary galaxy in the group of 4. They formed quite a tangle with NGC1741A and PGC16573 overlapping to form a distinct ‘tick mark’.NGC1741B formed the lower right corner of the groups ‘blocky’ outline with very faint PGC16571 (mag17.9). Not part of the group but close by in the sw of the view was another relatively prominent galaxy well within the fov IC399 round and bright at mag 15.9, see my sketch here.

It is now past midnight and we are into Christmas Eve, my next group is in Eridanus ‘the river’ and long sinuous constellation that wends its way from dazzling Rigel at the foot of Orion down past Fornax well below my horizon. HCG30 marks almost the most northerly part of this constellation. Again this group had 4 members but this time they covered a slightly wider field so didn’t form an interesting over all outline with my set ups as the first two did. What this group lacked in overall aesthetic profile it made up for in the fact that there was some structure visible in one if not two of the member galaxies. Member (a) PGC15620 showed 2 spiral arms on the monitor the most southerly member (b) PGC1561 showed itself to be elliptical; (c) PGC15624 the most northerly member and (d) component PGC15636 are considerably smaller and fainter. A testing group overall although A & B members were relatively easy, I had to locate the group by patiently moving the RA & DEC controls until I had the coordinates exactly. See my sketch here

My last sketch of the night was the most challenging, located at 01.30 with a mixture of star hoping to get me close and final searching using RA & DEC controls to match the coordinates HCG32 in Lepus was well and truly in the murk of the southern horizon for me and will test any visual observer from the UK to utmost limits to locate. As with the previous three the group has 4 members, with 3 in a N-S line with one to the left in my sketch. (a) Component PGC16583 close to a mag 12.9 star is the largest and brightest as one would expect with a circular outline, (b) component PGC16578 is the northern most member surprisingly showing as being mag in my Sky Map software, the original Paul Hickson Atlas lists it as being mag 15.28, closer to my sketch rendition I would say. (c)PGC16587 and (d) PGC16584 for a close central pair of faint tiny smudges close to a mag 3.2 star.

A testing observation and one I’m pleased to have under my belt, see my sketch here.

 By the time I had identified all the group components it was 02.30am and time to get to bed as there would be demands of the festive season aplenty upon me early in the morning of Christmas eve.

 

Happy Christmas all 🙂

Time well spent on the Moon

Blog Saturday 17th and Sunday 18th  December 2011

 

Lunar observing and sketching is something that I’m guilty of neglecting for a few months now, mean while my 2 sketching friends Frank McCabe & Chuck Hastorf across the pond in the US had been prolific in this department.

It was actually my intention to observe Mars this morning, I never got there! Using the two telescopes still set up from the previous ‘Jupiter experiment’ that I had shared with Es Reid. To recap the 20” was showing through the later Watec 120N+ video camera and an x4 TeleVue Powermate lens. The 6” refractor was running through the older 120N Watec and a standard x2 barlow lens.

As part of ‘hoping’ to the target process I sent the scopes to the Moon, the terminator then caught my attention and held it. I was soon focusing my intention on one particular crater, its image completely filled the monitor the magnification factor was very high with a small chip and focal length of 7552mm (F15), at the time the crater was unknown to me, after sketching (view here)I incorrectly identified it as Davy. It was Bill Leatherbarrow BAA President and Lunar section Director who correctly identified it as “Ptolemaeus”  “the crater to the north is Herschel, and the main crater on the floor is Ammonius. There are many low saucer-like depressions on the floors and a multitude of smaller crater-pits.”

Sunday 18th December 2011

The following morning I was again afforded the opportunity to get out and observe, once again I used the Moon and its terminator in particular as an alignment point. Today I deliberately stayed and sketched before I moved on to Mars.

The feature that caught my eye today was known to me, it was Plato with dramatic inky shadows cast across its near 100km of smooth floor. The sprinkled peaks of the Montes Teneriffe below Plato in my sketch also caught my eye once again with their dramatic fang like shadows and also by their brilliant ice white peaks, this is what I tried to capture in my sketch which can be seen here.

Coincidentally my friend and fellow BAA Lunar section member across the Ocean, Chuck Hastorf had been captivated by the Plato shadows the previous morning and had sketched Plato too, researching that a crater rim high point known as ‘plato zeta’ See chucks sketch here.

Chuck writes:

 

Hello Dale

 

I was curious about the striking long shadow cast at the lunar sunset on the 14th.  Lunar day 22.  After some research I found: 

 

 “…Elger mentions on the west rim, casting the longest shadow at sunset, was called Plato Zeta. “

Let’s see, if the diagonal in the NexStar gives a mirrored image, then..The shadow originated on my right and stretched to the my left….my head hurts,  If it was Plato Zeta, the name Plato Zeta is worth remembering.  I’m going back next Lunar Day 22.  Hopefully, the weather will cooperate and seeing will improve.

 

Clear Skies

 

Chuck

 

I then moved onto Mars surprisingly getting it onto the small ½” chip easily despite the very narrow fov at the long focal length, this was equal to very high magnification and not surprisingly Mars was a boiling, gibbering mess on the monitor, a polar region was distinct and there was some darker features in the swirl but totally unidentifiable. I opened the door and walked up the steps into the observatory and using the eyepiece port on the flip mirror fitted to the 153mm F9 refractor took a visual on Mars, the eyepiece was a 19mm running through a x2 barlow  giving 145x, the image was tiny, showing a gibbous phase clearly and polar brightening. I took that eyepiece out and dropped in a 7mm Ortho fitted with my preferred Neodymium filter giving 393x and again a pretty messy view, what did become evident was brightness running down the limb opposite to the terminator edge. It was pleasing to look upon Mars rather that a serious or scientific observation. It didn’t even match my observation way back in September from Kelling under exceptional seeing conditions. 

There ended this early Sunday morning session, Dale

An evening of tweaks & Jupiter

Blog Saturday 10th December 2011

 

Es Reid Cambridge optical designer and engineer is a frequent visitor to our home and my observatories. Without Es’s technical expertise much of the work done at the observatories would happen, things would be much ‘lower key’ and agricultural.

I invited Es over on Saturday afternoon with the lure of a good dinner, the bait proved, as it often does to be irresistible.

Our guest arrive just after 3pm, he brought with him the refurbished HST drive motor. Es kindly sorted this out for me with a small Cambridge electric motor repair specialist, cost was £100 but I think this will be money well spent as it keeps the telescope and the gramophone motor drive conversion by Will Hay in the early 30’s together. Es also returned Aubrey’s Nikon binoculars which had gone out of collimation following our summer trip to Italy they again worked perfectly much to Aubrey’s delight.

After tea in front of a roaring log burner we ventured out into the cold observatory it was a cold afternoon, the temperature was dropping fast as night approached and there was a bitter wind blowing. Es first took a look at the mirror support system as I continue to have problems with collimation as the mirror shifts and sticks as I moved about the sky, this became obvious as each time I moved the scope the piggy backed 6” refractor and the 20” mirror would go out of  alignment!

Es loosened off some nylon mirror sidewall supports and announced although not perfect things were a little better. It would get a testing after dinner when we intended to run the Watec 120N+ video camera on Jupiter at a long focal ration to see what the view was like.

With a good helping of fine homemade cottage pie enjoyed we got back out into the observatory and got going on Jupiter. The evening was spent collimating the telescope mirrors and the 2 telescopes to each other, slewing about the sky testing the accuracy of the goto, Es declared himself dissatisfied with this and attributed it in the main to the crude clutch the mount employed which amounts to 3 small 10mm nylon tipped bolts which screw down onto the RA & Dec shafts. The Dec is just about OK but the RA can’t be held firmly and as the slew ends a degree of slippage takes place giving inaccuracies. Es & I discussed modifications and a remedy will be affected in the near future.

To finish off with we had both Watec cameras on Jupiter the older 120N on the 6” refractor doesn’t have a true planetary session where the later 120N+ does, we had that running through the 505mm mirror. Settings on both were set for very fast exposure with gain right down. The camera on the 505mm mirror was running through a Televue x4 Powermate and the camera on the refractor through a x2 barlow considering these were deep sky cameras and not planetary web cam jobbies the views were very good, the x4 TV Powermate gave the 505mm a focal length of 7552mm at F14.96, I was once told by someone who knows much more about such things than me, Bern Kapinski of Modern Astronomy I think? That a Watec camera is roughly equal to an 8mm eyepiece in terms of calculating magnification that is 944x! Can this be right? OK let’s be conservative and say 10mm that is still 750x the Jupiter image on the monitor was very large I would say approx 70mm across! It wasn’t razor sharp but it was very steady with the 2 dark elongated barges in the SEB that we commonly see at the moment very prominent. I wanted to sketch the image which was worthy of such an effort however the messing about with collimation etc continued Es is never satisfied an feels things can always be better, impatient me I just wanted to sketch. The story is that by the time we had an image on the monitor steady again seeing had deteriorated. I grabbed a single short exposure frame with the laptop capture card which took a good while for me to figure out how to use! This image isn’t that representative on what was displayed on the montor they never are I have found.

Es then wanted to take a video run so he could play around with it in Registax software at home, unfortunately neither of us could find out how to do this L

It was at this point with the images dimming and brightening on the monitors in quick succession due to fast moving cloud arriving from the west that we closed up. I left everything set up as was in the hope that I could rise at 5am and see what Mars looked like with the set up on the 20”. That didn’t happen the night remained cloudy and turned to rain early the next morning.

Still we had good fun, after all that is what this is about, enjoying ones self.

Dale

Finding Hickson’s in the windy mornings

Blog Monday 5th and Tuesday 6th of December 2011

 

With my eye firmly fixed on the Hickson Compact Galaxy Group project I was getting to bed at a reasonable hr to take advantage of the early morning Moon free clear skies the current colder snap was giving. The alarm waking me just before 5am gives around an hour to get a brew made and out into the observatory, everything fired up, a target group located and sketched before my daily routine kicks in at 6am or thereabouts.

Leaving the back door of my warm but not too warm house out into the chill of a dark pre-dawn day gives me a thrill with the bright outline of the Plough of Ursa Major at the zenith, I get butterflies as I walk the dozen or so yards and unlock the observatory as I do so I look over my left shoulder to the south and see magnificent Leo high and level with the burning ember of Mars in his belly. The anticipation, the childlike excitement of being out in the dark, needing to be quiet, when all around me are asleep in bed and unaware of what I’m up to.

So I have set the scene so now down to the results On Monday I picked HCG46 to go for first, this turned out to be tricky as it wasn’t in my Sky Map Pro 10 database so I went to the location detailed in Paul Hickson’s Atlas but wasn’t sure if I was seeing faint galaxy smudges or not, mainly due to the fact my mount & goto aren’t quite up to Paramount standards and secondly because it was windy a wind laced with frosty cold, this shock the big telescope with the 6” on its back constantly smearing and blurring the video images. I gave up on this and moved a little lower into Leo where the scope would get a little more protection from the walls onto a brighter group HCG47. This was more like it although I had to wait for quite a while until I got a lull in the NE wind and a steady image I could sketch, I think a really still morning would have yielded more detail. They sky Quality meter registered 20.7 when pointed at the observed area. This group was dominated by a lovely n-s extended spiral showing me structure the other members were obvious but not structurally interesting, the galaxy just off of the northern tip of the primary member had 2 stars close east and west, the western that close that in the conditions it looked more like a brightening in the galaxy than stellar, checks with Aladin later showed it to be a star. I was generally pleased with the observation realistically one successful and accurate observation recorded in a sketch is all that I could expect in an hour.

Tuesday morning was an almost carbon copy of Monday, clear & cold however the wind speed had dropped a little, it was still enough to shake the scope about and interfere with viewing however. Undeterred and with my mug of hot tea I went back to HCG46 and again I met with trouble, in the end I settled on a galaxy PGC30128 that showed up in Sky Map Pro and was very close to the coordinates of 46, I thought this might be the primary member. I found it OK just to the north of a reasonably bright star with a distinct little Triangulum asterism to the north of the field, I sketched the scene noting in some tiny faint smudges in the hope (now vain) that they were galaxies and not v faint shaky stars. By the time I concluded I knew this didn’t add up and it was another failure on 46.

I had wasted valuable time and a hint of panic set in, I hate not to produce a creditable drawing from a session especially one where I have had to sacrifice sleep. I decided that the group below Leo in Hydra were too low in a sky starting to brighten, so I went to the Lion’s rear for HCG53, a brighter group. Again the wind was trouble and I had to wait for a steady view in the end I had to put pencil to paper, better conditions i.e. less wind and a darker sky, it was now past 6am and I would have pulled out more detail. That notwithstanding this is a reasonable representation and I even caught an unidentified tiny galaxy to the right of the centrally placed B & C members. NGC3697 showed some nice spiral structure, greater than my sketch indicates during the odd less windy moment. Not complaining, I was a little late now for getting ready for work but I had another Hickson under my belt.

Dale

Getting the Vets in

Blog Saturday December 5th 2011

 

I had arranged with some good friends, husband and wife, Rob & Helen White, both Vets and keen naturalists to come over to visit the observatory and hopefully take a look at Jupiter. As usual it had been a hectic day, Aubrey & I arrived back at Chipping almost exactly at the time I had arranged for Rob & Helen to come over, indeed they were already there when we got back.

Rob is a keen antiquarian book collector and had kindly brought along some examples of his exquisite collection for the boys and I to take a look at, some of them very rare indeed. In return we showed them some of the books in our Astronomical collection, especially those linked with the Hay, Steavenson telescope (HST). After enjoying books over tea, we moved outside and looked at the observatory housing the 20” reflector and 6” refractor, either I’m getting weak in my old age or that roof is getting harder & harder to open! We under a partially clear sky so it was looking good for a spot of observing for the guests. While we looked at the telescopes discussing various aspects Aubrey was opening up the Fry observatory housing the historic HST, we soon moved across and I pointed the heavy and venerable telescope towards Jupiter, the low power view was lovely and showed a dark spot in one of the equatorial belts, a shadow transit perhaps? The guests were invited to take a look and become accustomed to the telescope, ‘slo mo’controls and focusing, being scientists they soon had the hang of that so we increased the power and put the binoviewer in place, unfortunately seeing only proved to be mediocre so I had to drop back on the magnification by using a pair of 32mm plossl’s. The view was periodically reasonable and during those steady moments the dark spot showed itself not to be a shadow transit but one of the 2 prominent deep brick red barges that sail the NEB at this time, as clearly shown in here in an image by Simon Kidd . Rob & Helen clearly enjoyed the view as well as the age, presence and provenance of the telescope. Cloud was building from the west as we transferred across to look at the Moon, the terminator was rugged and breathtaking and again Rob & Helen were impressed, as was I. We took it in turns to observe; I increased the power a little and moved out to the limb. Another round of turns at the eyepieces and the cloud was just about solid. Rob & Helen went indoors where Aubrey showed them what we refer to as ‘Will Hay’s travel scope’ a lovely Georgian 2” Merz refractor whilst I closed up in case of rain. After a little more conversation our guests departed both seeming very pleased at their look out into the amazing solar system. Sharing such moments with others is totally priceless, I hope they enjoyed the experience as much as I did.

Dale

An early morning ‘brew & slew’

Blog Friday December 2nd 2011

 

With the Moon now starting to interfere with evening Deep sky observing and the forecast saying the east would clear out after midnight and turn frosty I set my alarm for 5am, this would give me a hour or just over before I had to get ready for work.

Thankfully the forecast turned out to be correct and I got out under a fine sky with a nice brew of tea around 5.15am. It was my intention to make a start with one of the many Hickson’s in Leo. I happened to choose HCG44, also known as Arp 316 in the mane of the Lion, for no particular reason. It turned out to be a fine and interesting choice, being a group pretty much everything that H17 my last observation was not. It covered a large field 3 of the 4 member’s revealed good structure. I had observed all the members before but not as a group, not as a Hickson and not with the 20”. As the fov needed to catch all 4 was so large I had to refit the focal reducer that I hadn’t be using, not only that, I had to unscrew both reducer and nose piece as much as was practical to increase the field of view as far as possible, even then I only just got all members in. In the centre of this group is a stunning double act NGC3190 is an edge on with a lovely dust lane seen prominently in my sketch, next to a nice spiral with 2 prominent arms one up, one down, this is NGC3187. To the lower right of the field is NGC3185 a barred spiral with 2 prominent arms finally the only member without structure displayed is seen to the upper left in the field this is NGC3193 at mag 11.62. A very nice group and a fine bonus before a day at the office.

Dale

Keeping up with the Jones’s

Blog Tuesday 29th November 2011

 

A rather good clear night gives me another opportunity to pick off a few more of the Hickson compact galaxy groups. Although I actually started the evening with another challenge this on set for me by my good Stateside friend Frank McCabe, he wrote to me saying that he thought  the large a rather diffuse planetary nebula in Pegasus ‘Jones 1’ aka PK104-29.1 was one that I should be able to get relatively easily with my set up. I wasn’t so sure I’m not so comfortable with diffuse planetaries and other diffuse nebulae, the truth is that the Watec cameras aren’t very effective at the wave lengths predominantly generate by these objects, and filters have proved to be not very helpful due to the relatively short exposures these cameras offer. I took a look at Aladin which normally indicates what I’m likely to see, well in the case of galaxies especially. The image didn’t bode well; it was a large backward facing C and faint. Enough of the fears, I went for it, of course I did, it was well placed and I located its place in our galaxy with relative ease, there was a hint of brightening on the monitor but no more and it wasn’t C shaped or even draw-able. I decided to try a filter if for no other reason that to say I had ticked that box. I used a 1.25” Lumicon visual UHC filter that I have, screwing it into the cameras nosepiece I refocused using some brighter local stars until they had gone from bloated to sharp, I then returned to the location of Jones 1 and cranked all things to max, low and behold there it was, not dazzling, but there in all the right places with some regions brighter than others, a grouping of faint stars in the centre, a very pleasing result. I made a sketch which you can see here and moved on, no time to waste; it was a work day in the morning.

My target was Hickson 17 in Aries, because it was well placed, I hadn’t done any home work on this one so didn’t know what to expect. I was surprised at how compact this one was and how tiny the5 members appeared, certainly no spiral structure to be seen here, the magic lay in their vast distance and faint magnitude. In fact my planetarium software listed the faintest member PGC8559 as being Mag 19.3, that is likely to be a photographic measurement but that not withstanding it certainly isn’t brighter than mid 18th mag so quite impressive, it certainly came a went on the limit of camera the cameras grasp. All members were PGC catalogued I found out after I sketched them, I later labelled another outline sketch.

And so to bed, pretty satisfied. Dale

Making a start on the Hickson’s

Blog Saturday November 26th

 

Stewart Moore the section Director of the Deep Sky section of the BAA and Owen Brazell Galaxy Section Director of the Webb Society and also Stewart’s Deputy at the BAA had come up with the fantastic idea of a join society project of observing and imaging the challenging Hickson Atlas of Compact Galaxy Groups. This list of tight faint galaxy groups numbering 100 and are well placed in most instances for observation from the northern hemisphere, including UK latitudes. Catching these distant galaxies visually will require large aperture telescopes or CCD cameras to image them. see map here

My 20” mirror and Watec deep sky video camera combo are well suited to finding these in the depths of the universe.

Saturday night was my first opportunity and attempt at starting on the list, I won’t drag this evenings observing out for too long, it was a disaster, I had camera connection issues, the telescope mounts goto was not working correctly and I spent a number of hours not observing any of the Hickson groups!

 

Blog Saturday November 27th

 

Another clear night was delivered offering a chance to wash away the disappointment of the previous evening.

I started early evening under the late autumn sky which is truly dark by 5.30pm local time. Working within the square of Pegasus towards the lower right corner I soon had Hickson 93 also known as Arp 99 on the monitors; yes the 6” refractor and older Watec also picked the group out, with little drama but 4 of the 5 members were there for sure.  Through the 20” the view was dominated by NGC 7549 a very attractive barred spiral at the north of the group with a overall outline the that shape of an oat seed with in which could be seen 2 dramatic bright arms, a real beauty. The other members varying in size, magnitude and slightly in shape were more your characteristic distant fuzzy. After sketching I moved east through the square into Aries were I caught my first sight of Hickson 18, I was rather bemused at first as there are chain of 4 galaxies the upper 3 so close they appeared to overlap and form a kind of Y shape (from the north down PGC 10042, PGC10043 & UGC2140) they ranged from mag 15-16, to the south with just a small gap from the ‘Y’ is UGC2140a the brightest of the 4 at mag 14.1 showing a core and elongated outline, it lay just above a bright mag 10.2 star that set the whole group of to resemble something of an exclamation mark!

This is a very interesting group, unusual and quite challenging to make out who is who? It did tell me that Paul Hickson back in the 1980’s was not exaggerating when he called them “compact”

That was it for tonight, I was well pleased with my observations, the failure of the previous night forgotten and the excitement at the prospect of other Hickson’s elevated 🙂

 

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