Category Archives: Open Clusters

Observing 10th October 2010

After seemingly endless clouds, gales, rain and murk for the past few weeks, the sky finally cleared and I was able to get out and knock off some Herschels last night, 10th October.
I decided to stay entirely within the borders of Cassiopeia and the list was mostly open clusters, apart from one galaxy. I’d already done some of the H400 objects within the constellation but still had a lot more to do. I also looked at non-NGC clusters that were nearby.

Date: 10th October 2010
Conditions: Cloudless, cool (10C), no dew, a little mist
Seeing: I, excellent
Transparency: II-III
NELM: 6.2
Equipment: 12″ f/5 Dob, 22mm Televue Panoptic (69x), 15mm Televue Plossl (101x), UHC filter

NGC 129, open cluster in Cassiopeia – Large and fairly rich. Triangular with dark area cutting through it. 69x

NGC 136, open cluster in Cassiopeia – A bit of a bugger to locate as it’s faint. Round, nebulous background with a scattering of faint stars on top. Pretty boring. 69x

NGC 225, open cluster in Cassiopeia – A complete contrast to the previous cluster. Bright, large, irregular, loose cluster. 21 bright stars plus some fainter ones among the bright ones. 69x

NGC 381, open cluster in Cassiopeia – Faint, rich and round. Detached. A chain of stars goes north from the main body of the cluster. Nice. 69x

NGC 436, open cluster in Cassiopeia – In same field of view at 69x as NGC 457 (also on the H400 list, but I’d observed this at an earlier date) and they both make a lovely sight. 436 is a small knot of stars and is irregularly shaped. Fairly rich with half a dozen or so brighter stars and many more fainter ones resolved. 69x, 101x

NGC 559, open cluster in Cassiopeia – Quite rich but relatively faint. Compressed. Some brighter stars (around mag 12) superimposed on a hazy background. Nice. 69x

NGC 637, open cluster in Cassiopeia – Compact and fairly bright o.c. There are seven brighter stars, plus more in the background. Crescent shaped. There’s a double star just to the east. 69x, 101x

NGC 185, galaxy in Cassiopeia – Elongated glow, NE-SW with some concentration towards the centre. Core’s not stellar, more diffuse. Quite large. 69x, 101x

NGC 7789, open cluster in Cassiopeia – This one’s an absolute beauty. It’s very large and extremely rich in fairly faint stars. There are no bright stars anywhere in this cluster but it’s now definitely one of my favourites. The cluster is round, and the stars are all of the same, or similar, magnitudes and there’s a hazy background hinting at even more stars – there must be hundreds.
There are also dark areas, semi circular patterns and this makes the cluster look like a rose seen face on. 69x, 101x.

NGC 7790, open cluster in Cassiopeia – Small, compressed, quite faint, irregular open cluster. Extends east-west. 69x, 101x

NGC 7788, open cluster in Cassiopeia – Just north of 7790, this is a larger, looser, brighter, sparser cluster than 7790 is. Irregular. 69x, 101x

Frolov 1, open cluster in Cassiopeia – Not much to write home about! Very small and sparse. The stars are faint and scattered. 101x

Harvard 21, open cluster in Cassiopeia – A scattered faint group of 8 stars. Irregular. 69x, 101x

King 12, open cluster in Cassiopeia – A small, bright knot NW of H21. Two bright stars and a lot of fainter ones. Compressed, not rich. 69x, 101x

NGC 654, open cluster in Cassiopeia – Nice o.c. Not round but irregular. Compressed. Quite bright. Nice. 69x, 101x

NGC 1027, open cluster in Cassiopeia – Large, irregular, bright o.c. Rich. Identified by 7th magnitude star near the centre. Other stars and 5th and 6th magnitude plus many fainter ones. 69x

Melotte 15, o.c. with nebulosity in Cassiopeia – Large, irregular sparse cluster. The nebulosity is only visible with the UHC filter. 69x, UHC filter.

I packed up at 2215, after an excellent session.

Observing, early morning 17th September 2010

This was taken tonight, not last night, but is otherwise identical. Lovely pink sunset with the promise of things to come.

The forecast looked good but, unfortunately, a waxing gibbous Moon was in the way, not setting until 0020 BST (one of life’s mysteries is this – why does a waning Moon seem to take forever getting out of the way, yet the waxing stage seems really quick, only slowing down as it approaches Full Moon?). Because of this I decided not to go outside until it was out of the way, although I can never take a nap in these situations!

Date: 17th September 2010; 0130-0300 BST (0030-0200 GMT/UT)
Conditions: Cool, totally cloudless, no wind, slightly dewy
Seeing: Ant II-III
Transparency: I (excellent) – II (very good) later (M33 visible with unaided eye)
NELM: 6.5+
Equipment: 12″ f/5 Dob, 22mm Televue Panoptic (69x), 15mm Televue Plossl (101x), 11mm Televue Plossl (138x)

NGC 1857, open cluster in Auriga – Faint, fairly rich, irregular. 69x, 101x

NGC 1175, galaxy in Perseus – Faint, not quite round. Diffuse elongated core. 69x, 138x

NGC 1177, galaxy in Perseus – NE of 1175. Very faint indeed. Barely seen. Possibly elongated. 138x

NGC 1245, open cluster in Perseus – Very nice large irregular cluster. Faint, fairly rich. Many faint stars. 69x, 138x.

I packed up at 0300 BST after a less successful session than I hoped for; I couldn’t seem to track down most of the Herschel IIs I went for, yet there was nothing wrong with the sky conditions, however I put that down to being tired. An example of tiredness-related cock-ups was when I made some soup and attempted to defrost some bread in the microwave – I ended up nuking it because I pressed the wrong button! Still, an observing session with four objects is better than no observing session at all and a lot better than my sorry effort the other evening (9th September 2010).

However, observing in the early a.m. is a nice way to spend the time, maybe better than evening sessions. There is no-one around at all and it is very quiet, although when I dropped an eyepiece on the shed floor – fortunately without damage – it sounded like an explosion! Likewise when I went back to the kitchen to make the soup, the kettle sounded as loud as a volcano.

Apart from the sound of the horses in the next field, the snoring of my darling dog in her basket, the rustle and squeaks of rats and mice in the hedge and the snuffling of a badger in the lane, there were no other noises. That’s how I like my observing sounds to be. No machines, no loud TVs from the neighbours across the way, no music, just animals and the other sounds of the night.

Observing 12/13th September 2010

‘I got the poison, I got the remedy, I got the pulsating rhythmical remedy‘

…so goes the lyric of Prodigy’s song Poison, and fairly appropriate as they were coming down the valley loud and clear from the ‘Bestival’ last night – also appropriate as I found a Death Cap toadstool in the garden yesterday, which I promptly threw in the bin out of reach of the dogs (DCs are the most poisonous toadstools known). I like the Prodigy, but I don’t like the light pollution from the festival that was wiping out the north western, and most of the western, sky or Rob da Bank’s DJ set of bad music that went on to almost 4am this morning (1am’s fine, but later than that is not. I bet they’ve pissed off the entire Arreton valley). At least that’s over for another year.

The weather forecast called for it to clear at sunset, the BBC (Met Office) said it would be clear all night but the others (Accuweather, Metcheck and The Weather Outlook) disagreed, forecasting it to be partly clear, and, in the end, they were right and the BBC were wrong.

Would this clear? Btw, the tree is dead but the birds like it so it stays

Conditions: Cool, but not cold, some drifting clouds at first, becoming murkier later. Slight dew.
Seeing: Ant II, very good
Transparency: III to IV later (III. Clear, some haze visible. Milky Way still visible but not detailed; IV. Milky skies, moderately hazy but observing of brighter NGCs doable/drifting cloud).
Equipment: 12″ f/5 dob, 22mm Televue Panoptic (69x), 15mm Televue Plossl (101x), 8mm Televue Radian (190x), OIII filter. MegaStar 5 chart printouts, Sky Atlas 2000.0, Pocket Sky Atlas and NSOG Vols I and II

NGC 6996, open cluster in Cygnus – Located within NGC 7000 (the North America Nebula). Spiral shaped cluster of 30+ fairly faint stars. Spiral is anti-clockwise. Fainter stars among the brighter ones. Chain loops off to north before turning west. Quite large. Moderately rich. Observation interfered with by drifting clouds. 69x.

NGC 6824, galaxy in Cygnus – People think of Cygnus as a realm of open clusters, PNes and nebulae, but galaxies lurk here too. Fairly bright and easy to find as it stands out against the background sky. Almost round. Brightens gradually towards the core. Core diffuse, not bright. 69x, 190x.

NGC 6894, planetary nebula in Cygnus – A bit of a sod to find, faint and quite small. Not helped by milky sky. At low power, there is a hint of something fuzzy and oval. An OIII filter brings it out as a filled-in oval. At high power, and with the OIII,  it has a darker middle and looks annular. 69x, 190x, OIII filter.

The latter observation was being affected by the fireworks from the festival, I could see the flashes in the eyepiece while looking at NGC 6894, which was hard enough to see as it was. So I abandoned Cygnus and moved over to Triangulum and Aries, which were just clearing next door’s oak trees from my position.

NGC 772, galaxy in Aries – Round, quite faint (low), condenses to non-stellar, but obvious, core. 69x, 101x.

NGC 672, galaxy in Triangulum – Quite faint, elongated west-east. No brightening in centre. Faint halo around bar. IC 1727 nearby but very faint that I want another look at it on a better night. 69x, 101x, 190x.

NGC 925, galaxy in Triangulum – Elongated, faint. Evenly bright with halo. Some foreground stars. 69x, 190x

NGC 890, galaxy in Triangulum – Round, bright. Bright non-stellar core. 69x, 190x.

By now, just before 0100 BST (midnight GMT/UT), the sky was getting progressively worse, with a lot of murk scattering light about so I packed in. There were a few other objects I hunted for, among them NGC 1156 and NGC 1012, both in Aries, as well as NGC 6857 in Cygnus and the infamous NGC 6772 in Aquila but these were all wiped out by murk and will have to wait until a better night.

Observing 3rd/4th September 2010

Another clear night, another observing session. That’s four in a week! I missed a couple of nights over the course of the week as they were murky and foggy and therefore no good for deep sky observing. Last night started off a little murky but gradually improved as the night went on.

Date: 3rd/4th September 2010
Conditions: Cool but not that chilly, a bit murky at first but improving later. No Moon. Started off clear, clouding over later.
Seeing: A I, superb.
Transparency: III, improving to II later (until clouds came)
NELM: 6.1 to 6.5 later on
Instrument: 12″ f/5 dobsonian, 22mm Televue Panoptic (69x), 15mm Televue Plossl (101x), 8mm Televue Radian (190x), 5mm Radian (304x), OIII filter

NGC 6804, galaxy in Aquila – Faint, slightly oval, stellar core. 69x, 190x

NGC 6772, planetary nebula in Aquila – I wasted more than 30 minutes looking for this (not plotted on atlases) and eventually gave up. Annoying. Will have another go at this with a MegaStar chart I’ve just printed out.

NGC 7448, galaxy in Pegasus – Bright, elongated NW-SE. Brightens gradually towards the centre. 69x, 190x

NGC 7814, galaxy in Pegasus – Bright and easy to find, located near ϒ Peg. Elongated NW-SE. Brightens towards the core which is bright but not stellar. 69x, 190x

NGC 7217, galaxy in Pegasus – Bright, round, condenses to bright but non-stellar core. 69x, 190x

Pegasus is now complete as far as the H400 is concerned, as I’d already observed some objects in it last autumn.

NGC 7686, open cluster in Andromeda – Irregular. Dominated by two bright yellow-orange stars. Loose. Fainter stars in background and around the two bright ones. Not particularly rich. 69x.

NGC 884 and 869 – the Double Cluster in Perseus – These are lovely things in a wide field eyepiece. Both clusters fit neatly into the field of view of my 22mm Panoptic (69x). If each one was isolated it would be a pretty object in its own right but, both together make one of the finest DSOs in the Northern Hemisphere – in fact the DC is (are) the best open cluster(s) in the sky and I genuinely think that we outdo the Southern Hemisphere with this one.
NGC 869 is smaller and more compact that its neighbour, 884. There are 2 bright stars in the centre, plus a compact triangular pattern of stars in the centre. 69x
NGC 884 is larger and looser. No central group of stars, unlike 869; there’s empty space at the centre. The stars of 884 are more concentrated to the western side. 69x.
All stars in both clusters are white.

NGC 650-1 (M76), planetary nebula in Perseus – Very bright indeed, looking like a miniature M27 (in fact, it is called ‘Little Dumbell’). It has a bi-lobed appearance with an outer shell extending off to the south west and north east; the south western one is slightly brighter. The south eastern lobe is slightly brighter but smaller, than the north western one.  An OIII filter brings it out nicely. 69x, 101x, OIII filter.

NGC 1023, galaxy in Perseus – Bright, elongated east-west. Condenses to very bright core. 69x, 101x

By this time, it was beginning to get very cloudy, so much so they were interfering with observing. In fact it took me several attempts to see NGC 1023 as cloud kept drifting across the field of view.
I finished the session with a look at Jupiter, which was shining incredibly brightly, like a searchlight, high in the south east. While I am not a planet observer, preferring deep sky, I was glad I had decided to look at the giant planet because the seeing was so good, in fact it was perfect, that I had incredible views and could put the magnification up to 304x without too much degradation of the image.
The North Equatorial Belt was detailed, while the STB was a bit fainter and there were festoons in some of the other bands on the planet; the North Temperate Belt showed a lot of detail, as did both polar regions. The zones also showed some marbling. The SEB, of course, is still missing or very faint.

Observing 1st September 2010

The long-term forecast is not looking too clever for the autumn (if it was the Mess Met Office I would not believe it, but it’s The Weather Outlook, who got this year’s dismal summer spot on) so I’m going to fit in as much observing as I can until the weather breaks up.
I am also doing the Herschel II at the same time as the H400 and, looking at the list of them, I have already seen quite a few. Inevitable really, as I’ve been doing deep sky observing since 1993. However, my observing sessions always previously took the form of ambling round whichever constellation caught my eye at the time and I never really did a structured observing program in the past, so my observations are scattered around various note books and sketch pads, so I need to hunt them out and see what I have and haven’t seen. Still, re-observing things is not going to be a chore – although quite a few Herschel II objects not being plotted on Sky Atlas 2000.0 is a nuisance.

Date: 1st September 2010
Conditions: Slightly chilly, no wind. Quite a lot of dew.
Transparency: III but better at zenith (II). Mostly clear except from some high cloud. Jupiter bloated with halo, however, the sky was good at zenith.
Seeing: I, very steady
NELM: 6.1 (a little skyglow reflecting from high clouds)
Instrument: 12″ f/5 dobsonian with 22mm Televue Panoptic (69x), 15mm Televue Plossl (101x), 11mm Televue Plossl (138x), 8mm Televue Radian (190x), UHC and OIII filters.

NGC 6800, open cluster in Vulpecula – Large, loose irregular group of stars forming a distorted loop. Moderately faint. 15 brighter stars plus a load of fainter stars. Not rich. 69x.

NGC 6723, open cluster in Vulpecula – Not plotted on my Pocket Sky Atlas or Sky Atlas 2000.0, so I used the Night Sky Observers’ Guide Vol 2 to find its position and plotted it myself on both atlases. I really need to start using my Uranometrias more – in fact I am planning to buy the second edition for use while observing and keeping the old ones on the book shelves.
It’s easy to find 6723 once you know where it is. It’s in a rich field, more or less halfway between α Vulpeculae and Cr 399. Faint and small. Not rich. Triangle of stars (10th/11th magnitude) at the centre help identify the cluster. 69x, 101x

At this point a neighbour across the way put his garden light on, so his dog could see while it was going about its ‘evening constitutional’. I’d not seen this light before, or not noticed it (the reason being, our garden’s very large and what happens the other end of it is not always noticed from the house or patio; the patio was my previous observing place), but it was badly aligned and blitzed my observing area. I think I’ll be asking him if he can adjust it in future, if it’s trespassing then it’s aligned incorrectly.. After 15 minutes, I was wondering just how long it takes for a dog to have a pee (our dogs are in and out in two minutes!) when the light, thankfully, went off. These are the same neighbours who don’t have curtains on their upstairs windows, no doubt believing themselves unseen (uh uh, no you’re not!). If ever I win the lottery, I’m moving somewhere where I don’t have neighbours! Why are the general public so obsessed with lighting everywhere up?

Ok, now the irritating light’s been turned off, back to the observing and it’s time for some faint nebulae.

Sh 2-101, nebula in Cygnus – near a double star, this is an area of faint nebulosity. I can’t see it very well without a filter, but the UHC brings it out nicely. It’s a large irregular patch with dark lanes in it. 69x, UHC

NGC 6888, emission nebula in Cygnus – Located among a conspicuous group of five stars, this can be seen without a filter, but only just. A UHC filter brings out the crescent shape nicely but an OIII isn’t much of an improvement. With each filter there are hints of more extensive nebulosity to the north east of the crescent. the SW portion of the nebula is the brightest and the SE portion of the crescent is a bit fainter. 69x, UHC, OIII

Minkowski 92 (M1-92), (planetary?) nebula in Cygnus – This looks like a faint double star at low power but is obviously non-stellar at higher power. One ‘star’ is larger and brighter than the other and they are very close together. 69x, 101x, 138x, 190x.

I packed up at midnight, as the high clouds were moving in and it was getting mistier.

Observing 30th August 2010

Only a short session this one, due in part to a bad shoulder. Again, because of the Moon, I stuck to open clusters and went to do an H400 clean up run round Vulpecula.

Conditions: Clear, chilly, waning gibbous moon (around 65% full)
Seeing: Excellent, A1
Transparency: II-III
NELM: Not checked.
Instrument: 12″ f/5 Dobsonian, 35mm Televue Panoptic (43x), 22mm Televue Panoptic (69x), 15mm Televue Plossl (101x), UHC filter.

NGC 6882 and 6885, open clusters in Vulpecula – Two for the price of one, in same field of view. Large, irregular pattern of stars with a conspicuous bright white one (20 Vulpeculae) off towards the edge. This is supposed to be two clusters but it’s not easy to distinguish one from another. 69x, 101x

NGC 6830, open cluster in Vulpecula – Easy to find as it’s fairly near M27. Irregular, compressed group of 20+ stars with many more, fainter, ones in the background. 69x, 101x

NGC 6823, open cluster with nebulosity in Vulpecula – Small, compressed cluster with three stars in a tight diagonal line in centre. Many more fainter stars in cluster. fairly rich.
No nebulosity seen without a filter, but with the UHC filter I can just see some faint nebulosity. One for when the moon’s gone. 69x, 101x, UHC filter.

NGC 6802, open cluster in Vulpecula – Easy to find, located immediately next to Cr399. Quite large, fairly rich but needs moderate power to resolve. Looks misty at 69x, but stars begin to appear at 101x. Irregular, elongated north-south. Faint. 69x, 101x.

That finishes off the H400s in Vulpecula – I’d already seen NGC 6940 a while back. It also takes me past the magical 100-object mark, meaning I am just over a quarter of the way through the H400, as I am on 103 objects as I found out last night after a quick count of the ticks on my list.

Harvard 20, open cluster in Sagitta – A scattered group of 20 to 30 stars just SW of M71. Not much to write home about. 43x.

Packed up at 2330 BST as the moon was rising higher and its light was being scattered around the sky more than the previous evening, despite the phase being less.

Clusters by moonlight

It was the first clear night for a while so I decided to drag the scope out and do some observing, despite the waning gibbous moon. Because of the Moon, I thought that sticking to open clusters in the Herschel 400 was a good plan.
There was definitely an autumnal nip, as well as a ‘smell’ of autumn in the air. I put an extra layer on although, by the end of the session I was wanting to take it off as I was too warm.

Date: 29th – 30th August 2010
Conditions: Clear, slightly chilly, slight breeze
Seeing: Ant II – quite good, looked at Moon after session and there was not too much turbulence
Transparency: III – not too bad. Milky way washed out by rising moon
NELM: I didn’t check, although it would have got a right hammering from the moon and would be no better than 5.5 or 5.8.
Instrument: 12″ f/5 dobsonian with 22mm Televue Panoptic and 15mm Televue Plossl (69x and 101x)
2230 BST – 0015 BST (2130 UT – 2315 UT)

NGC 7044, open cluster in Cygnus – An absolute bugger to find. Small, compressed, not rich, faint. 69x, 101x

NGC 7062, open cluster in Cygnus – Much easier to find than 7044. Nice. rich, moderately faint cluster bordered by four brighter stars. Detached. Small. Stands out nicely. 69x, 101x

NGC 7086, open cluster in Cygnus – Compact, moderately faint. Rich. Detached. Set in a nice area. There are nine foreground stars with many more, resolved, fainter ones in background. Moon beginning to interfere. 69x, 101x

NGC 7128, open cluster in Cygnus – Very small, compact, compressed. There’s a ring of brighter stars on a hazy background. There is a conspicuous reddish star on the SE side, which is the brightest star in the cluster. Very nice. 69x, 101x

That finishes the H400 objects in Cygnus, so I moved on to Cepheus. The Moon was getting higher and about to clear the oak trees that border the north side of the garden, so it was beginning to interfere with finding things.

NGC 6939, open cluster in Cepheus – Compressed, rich. Bordered to east by distinctive pattern of three stars. Quite bright. Nice cluster. 69x, 101x.

NGC 6949, galaxy in Cepheus – The charts showed this was in the same low power field of view as NGC 6939, so I decided to give it a go despite the moonlight washing out the sky. At 69x, ‘something’ was possibly there, at 101x there was a definite faint elongated smudge. I’ll have another look at this when the moon’s out of the way. 69x, 101x

NGC 7160, open cluster in Cepheus – Easily found bright knot of stars, dominated by two bright white stars like eyes, plus 5 fainter ones. Many other fainter stars in background. 69x, 101x

By this time it was past midnight and, although I didn’t particularly want to go in, I packed up as the moon had cleared the tall trees which border the garden on the northern side and was becoming a real nuisance. I did have a quick look at the thing and it was quite spectacular, if horribly bright in the 12″ (felt a headache coming on, how do people observe this thing?? Too bright for me!) before wheeling the scope back inside and putting everything away.

I doubt if I’ll be observing tonight as, following closely on from my ankle injury, I’ve torn the rotator cuff in my left shoulder. Talk about accident prone!

Observing 7th-8th August 2010

The night of Saturday 7th August into Sunday was clear, although not as good as the previous Wednesday, so I pulled the scope out for a session looking for some summer Herschel 400 objects.

Conditions:
Clear, fairly warm, around 15C
NELM 6.0
Fairly humid with quite a lot of dew
Seeing II
Transparency II
Equipment: 12″ f5 Dob, 35mm Televue Panoptic (43x), 22mm Televue Panoptic (69x), 15mm Televue Plossl (101x), 11mm Televue Plossl (138x), OIII, UHC

NGC 6834, open cluster in Cygnus – irregular, attractive cluster made up of a line of 5 brighter stars crossing an elongated haze. At 138x, most of the haze resolves into faint stars.
There’s a separate clump to the immediate south of the main cluster, a knot of 10, or so, stars and another to the north, which has six stars.

NGC 6866, open cluster in Cygnus – Large, irregular cluster. Two chains of stars extend out from centre, one to the west and the other to the right. the western one is short and contains 7 brighter stars plus fainter ones. The eastern chain is longer and contains > 15 stars in a looping pattern.
There is a wide pair to the south.

Went after NGC 7044, but this was in the ‘dob hole’ and awkward to get at. One for another night, further into autumn when Cygnus is more to the west and that part’s easier to get at.

NGC 7027, planetary nebula in Cygnus – not on the H400 list but I was in the area. I am not sure why I found this easily and not 7044, but then a PNe’s easier to recognise than one of the myriad of open clusters and knots in the Milky Way in the Cygnus area.
7027 could easily be overlooked as just another star, as it is star like. However it isn’t stellar as at 69x it looks slightly fuzzy and an OIII filter makes it really jump out as a PNe.
At 138x its oval with no obvious darkening in the centre.

NGC 7296, open cluster in Lacerta – quite small, but conspicuous cluster near Beta Lacertae. Some stars resolved at 69, more resolved at 101x.

NGC 7243, open cluster in Lacerta – large, irregular cluster which fills the field of view of the 22mm Panoptic (69x). There are at least 23 brighter stars and many more fainter ones. Nice.

NGC 7209, open cluster in Lacerta – large and quite bright. Around 40 to 50 stars resolved. A very vague, rounded ‘m’ shape.

I finished up with a trip into the North America and Pelican nebulae, using my 35mm Panoptic and 2″ UHC filter. This was lovely, with wisps and and tendrils of subtle nebulosity everywhere. Here and there, hard edges were defined. Very nice indeed.

The next morning I found that, as the air heated up in the morning sunshine (Sunday was a hot day) my mirror had condensation on it. This is not good as repeated dewings up will cause the coating to deteriorate and fail and I don’t want to have to pay out for a recoating before I get my 20″. I opened up the scope and left it to dry out in the shed, with the shed doors open.
I posted on Cloudy Nights, asking how I can prevent this and most responses involved rigging up some kind of heating system. I am going to have to pay out for a car battery, an inverter and a lamp in the first instance and then, when I can afford it, a solar panel, at least 70w. However, a cheaper solution might be a large power pack with built-in inverter. That should run a low-watt lamp for a few hours to keep the mirror dry while the outside temps rise, although I am not sure exactly how long the charge would last, although some of these machines are pretty heavy-duty things. In the meantime, I have packed a couple of socks with silica gel and hung them inside the tube near, but not on, the mirror, then sealed the scope at both ends. I also went to Sainsbury’s and bought a bag of silica gel (not clay) cat litter which I’ll decant into socks and then hang inside the scope, tomorrow. Considering that quite a few of my socks have conspired to vanish, leaving only odd ones, they can do something useful! I blame the black hole that must be lurking somewere in the washing machine. The silica gel cat litter idea was also suggested on CN, stuffed socks and beanbags are the preferred method of holding them although, apparently someone once used a stuffed animal. WTF??!!

Observing 4th August 2010

A day of intermittent heavy rain and thunder gave way to clear skies during the evening, for once exactly as the forecast had predicted. The BBC and Metcheck’s forecasts both agreed, which seems to be a rare event in itself, so as it got dark I went and unlocked the observatory (I like the sound of that!) and pulled the scope out.
Earlier in the evening I had been in a pretty awful mood, no reason just a bad day, and felt more like saying ‘sod it’ and going to bed but I am very glad I didn’t as the sky turned out to be magnificent.
All too often when you step outside and look up, what looks promising at first often proves to be pretty average, even poor, but not last night. After getting dark adapted, I checked the naked eye limiting magnitude, using charts of Ursa Minor and Cygnus, and it was better than 6.5! We have pretty dark skies here, but better than 6.5 is fairly rare. Usually we get between 6.0 and 6.5 but last night was as good as 6.7! I would guess that the heavy rain and thunder had cleared the atmosphere of pollutants and dust. During my trips to the TSP, I’ve seen people using ‘iridescence’ in the Milky Way to gauge transparency – the more iridescent the MW, the more transparent the sky. The Milky Way was just like that here last night, iridescent, which we rarely see because of summer haze. Visible to the unaided eye were M13, M31 (later on when clear of the trees) and NGC 7000, the North America Nebula These were truly great summer observing conditions and well worth the long wait for.

Conditions: Clear, quite chilly
Seeing: Very good: Ant II
Transparency: Excellent – I, but a few odd bits of drifting cloud later on
NELM: 6.5-6.7, dropping slightly when the waning crescent Moon rose later on

First was Aquila and a hunt for the few Herschel 400 objects (three) that are here:

NGC 6781, planetary Nebula in Aquila – Set in nice starry field this is large and oval and quite bright. It’s easily seen without a filter but my OIII brings it out nicely. With the OIII, the pn looks slightly rounder with some darkening in the centre, without the filter I can’t see the darkening very well. Very nice object. 69x, 101x + OIII

NGC 6755, open cluster in Aquila – An attractive, small, compressed cluster set in a nice Milky Way field. Stars all white and evenly bright. Found at 69x as a misty knot, detached from MW star field.
101x shows a tiny, vaguely triangular clump of stars, with around a dozen or so on a hazy background and with a fainter patch next to it but at 138x, the cluster looks like a butterfly with the left wing richer than the right one. Very pretty! 69x, 101x, 138x

NGC 6756, open cluster in Aquila – Next to NGC 6755 in the field of view of the 22mm Panoptic (69x). It’s half a dozen stars on a misty background. Not as rich or as compressed as its neighbour. Framed by a bight star at either end. 69x, 101x, 138x

I saw on my star charts that the globular cluster Palomar 11, also in Aquila, was nearby, and given the excellent conditions I decided to have a crack at seeing it. After quite a few false starts I eventually found it. It’s in quite a rich area and nailing it down was a bit hard. It appears as a roundish brightening of the sky. Its low surface brightness and location in quite a rich part of the sky made finding it difficult but I caught it eventually. The observation of the night, I think. 69x, 101x, 138x, 190x

I also decided to see if I could see ICs 59 and 63 in Cassiopeia. Given the great night it would have been a shame not to go for the faint stuff.

IC 59, IC 63, diffuse nebulae in Cassiopeia – These faint little buggers are right next to Gamma Cas, so it’s necessary to put that out of the field of view before attempting to look for them. IC 59 is a faint fan-shaped patch while IC 63 is fainter still – in fact I barely saw 63, just a mere brightening in the area. 69x + UHC filter.

M31, galaxy in Andromeda – this lovely piece of eye candy is one of my favourites to look at and I always drop in to say ‘hi’ when I am observing and M31 is high enough. Last night’s conditions gave me the best telescopic view I have ever had of this galaxy. Under average skies usually only the bright central area is visible but last night, I could see (using my big 35mm Panoptic, at 43x) the galactic disk spreading out across and beyond the field of view, and the dust lanes. It was spectacular, to say the least.

NGC 6229, globular cluster in Hercules – Very bright and easy to find (made a nice change from Pal 11 and the faint nebulae in Cassiopeia!). Small and round with a dense core at 69x.
At 138x, it began to look granular with some stars resolved, especially the outer ones.
At 190x, individual stars can be seen and the halo and core are very bright, still looked granular across the face. 69x, 138x, 190x.

NGC 6207, galaxy in Hercules – bright and easily seen at 69x. It is completely overshadowed by its big and bright famous neighbour, M13. Oval, with a brighter core. Elongated northeast-southwest. 69x, 101x
I also popped over to see the big showy eye candy neighbour, which was absolutely superb as usual and in the same field they make a nice pair, with the galaxy being a hidden treasure.

Before packing in, I dropped in on Jupiter, which was shining like a big searchlight in the eastern sky, as the seeing was so good, and it looked decidedly odd without the South Equatorial Belt, which has totally faded away.

By 0200, the waning crescent Moon was substantially interfering with the sky conditions and there was more drifting cloud around so that, along with the fact my feet were by now very cold (I was wearing thin trainers) made packing up a Very Good Idea. So did the prospect of work in a few hours. So within five minutes, I’d pulled the scope back into the shed, chucked my charts back in their box, gathered up my eyepieces, locked up and headed back to the house.
As mentioned in my previous post, I’d found that the addition of wheels made my scope eyepiece higher off the ground. I knew it would be higher but not *how* higher. Consequently, viewing stuff at the zenith required standing on tiptoes. This was awkward and uncomfortable, as it hurt my calf muscles and toes, so some sort of small stool was a must. I found a little plastic step stool in Tesco this afternoon, for £2.50, which will fit the bill nicely.

From the notebooks – Australia 1997

I was going through old observing note books to scan in my sketches for my new website and I came across some from my observing trip to Australia in 1997. Those brought back some exciting and magical memories! I have decided to share some of the best ones here, as well as in their categories on my web site.
Click each image for a larger view.

NGC 5139, the great Omega Centauri. This ‘King of the Globular Clusters’ can be seen from southern Europe and the southern United States but has to be seen from the Southern Hemisphere in order to appreciate it in its full glory.
I looked at this wherever I went during both trips Downunder, from South America and also each time I have gone far enough south in the Northern Hemisphere to see it.
It’s huge, slightly elliptical and has a curious footprint-shaped area of less star density or obscuring dust, just off-centre. Spectacular.

8″ Cassegrain at 72x, Manly, Brisbane, Qld, Australia
August 11th, 1997

NGC 4755, the Jewel Box cluster in Crux.
This is my favourite star cluster, shaped like a capital ‘A’ and made up of blue and white stars of varying brightnesses but with a conspicuous red giant at the centre.

8″ Celestron SCT, Alice Springs, NT, Australia
July 21st, 1997

NGC 6822, galaxy in Sagittarius. This is Barnard’s Galaxy, a faint dwarf galaxy. The galaxy was a faint elliptical glow, quite faint against the background sky. Elongated 2:1 north-south with no central brightening.

20″ Dobsonian at 60x. Lions Camp Duckadang, Linville, Qld, Australia
August 26th 1997

NGC 55, galaxy in Sculptor.
At -39 S, this is too low to be seen from England, even from the IW (our theoretical cut off is -40 but with atmospheric extinction, not a chance). Huge elongated galaxy with a very bright, mottled core. Only just fits into field of view at 120x.

12.5″ Dall-Kirkham Cassegrain
Ellesmere, Qld, Australia
August 3rd 1997

NGC 7293, the Helix Nebula in Aquarius
I made two separate observations of this. One was from a rural site, the other from an urban one. Needless to say, I saw the nebula without an OIII filter more easily from the countryside than I did with a filter from the suburbs of Brisbane, where it was invisible. It was also 1st quarter Moon when I saw it in the suburbs.
Very large, oval ring with a low surface brightness and diffuse outer edges. No central star seen. Drawing made at the suburban site.
8″ Cassegrain at 72x, Manly, Brisbane, Qld, Australia
August 11th, 1997