Thursday, 31 March 2011

Light trespass

My observing site is rural with some skyglow from nearby towns, although this is only really noticeable when there's a lot of water vapour in the atmosphere and the sky is hazy. The house and garden are on farmland but we do have a couple of neighbours just across the public footpath which runs alongside the garden.
One set of neighbours, a retired couple, are fine, they only put lights on when needed and they don't have security lights. The ones next to them, however, have an upstairs light which is kept on - unnecessarily, in my opinion - all the time during the dark hours; normally I wouldn't object, because it's their electricity bill, but it faces my observing site. They also have a badly-aligned outside light in their garden which they switch on when they let their dog out, and this blitzes my observing area because the light goes right through the hedge - I don't blame them for lighting the way for their dog, we do the same for our three except our light is better aligned and doesn't shine anywhere else other than where it is supposed to. Our garden hedge that side (north) is quite high but the foliage doesn't cover all the gaps. It's not as bad in the summer because the leaves on the trees block out some of the light (I hope the neighbours don't decide to chop them down!).

I could do what other observers do and ask the neighbours to turn their lights off - and at least the security light isn't on all the time - but I feel awkward doing so. Therefore, I am going to rig up some sort of screen to stop the light trespass. I think the easiest way of doing this will be to put up a couple of easily removable poles and hang blackout cloth, or a large wooden panel, across them. The cloth will be easier to put up and store when not in use.

On a related note, the local council here have got a large grant from the UK government (only two other areas in the UK have got similar funding) to repair the highways, from resurfacing all the roads to renewing bus shelters to replacing the existing decades-old street lights. Apparently the new lighting is to be LEDs which will be brighter but, properly shielded, will not cause skyglow. I have read mixed things about LEDs and how they can make an illuminated area as bright as day, is this necessary? How bright do people need it to be? Is the nation really that scared of the dark? And it won't reduce crime: when living in London and Southampton, both large cities with loads of lights, I witnessed several muggings and was myself the victim of an attempted assault, all which took place at night in the full glare of the street lights. Scumbags need light to see what they're doing, same as anyone else. Night-vision CCTV would probably be more effective than brightly illuminating everywhere. But if LEDs, despite their brightness, are shielded and the horrible orange glow vanishes, to be replaced by dark skies above then I won't be complaining.
In the meantime, as this is a 25-year plan, why don't the Isle of Wight Council do what a lot of other councils are doing and switch off the lights in order to save money and reduce their carbon footprint? The IW Council is broke and having to make massive cuts yet won't turn off the lights after midnight. This makes no sense, it's the easiest way to make savings and reduce their carbon footprint, with the added benefit (and probably most important to astronomers) that we get our dark skies back. I have written to them, yet never received so much as a 'thank you for contacting us' - although I have emailed them again today. There is a so-called 'Eco Island' initiative here, where they want to decrease the carbon consumption of the Isle of Wight and increase our standard of living. This is all good stuff, but nowhere on their site have I found any references to wasteful lighting, so I have written to them, too. It will be interesting to see what their reply is, if they do reply. If they don't then we'll know it's a load of hot air, in more ways than one.

Sunday, 27 March 2011

Clear skies 2010

As some of you might recall, I've been keeping a (admittedly probably unscientific) spreadsheet of clear skies vs cloudy ones (I've had friends and relatives keep a note of sky conditions when I have been away, such as at TSP). I've made a note of clear skies, partly cloudy ones, and totally cloudy ones. Clear and partly clear both mean observationally usable ones as, even when partly clear you can still do some observing, even if it's with a pair of binoculars or half an hour with the scope.

According to my spreadsheet, 2010 had 111 totally clear nights, which is 30% of the total nights of the year. That's nearly one third which, considering a lot of people think the UK has a largely unfavourable climate is better than you'd think, and that's despite the horrible harsh and cloudy winter we've just had.
Clear and partly clear, added together, comes to 169 nights or 46%. That's getting on for HALF of the nights here in this part of England being usable for astronomy during 2010. Quite a surprise. Unfortunately, as ever, there's a caveat - the clearest time is May, June and July when all-night astronomical twilight keeps deep sky observing to a minimum. However, I will make a resolution to use those nights to observe and sketch the brighter DSOs, such as the Messier and brighter NGC nebulae and clusters, rather than just waste them. Maybe I will observe the planets, if any are around, as well. It will be a nice throw back to the time, 19 years ago, when I first got into observing and observed all through the summer twilight - my observing notes throughout the 1990s and early 2000s go right through June and July, no complaints about the twilit nights there!

So far in 2011, 24% of nights have been clear and 29% have been clear or partly clear, mostly during March. I will admit to not taking full advantage of them, mostly because they have coincided with the Moon's gibbous and full phases.

Looking at all the clear skies we've had - and I hope 2011 and beyond follow suit - I am going to make more of an effort to make use of them. It's not always possible to use every clear night, of course, as life tends to get in the way, as does tiredness and - let's be honest - laziness, but using half or more would be great.

Yep, Britain has got a reputation for being fairly useless astronomy-wise but - and it does depend on where you live, as we have a varied climate for such a small archipelago - it's not quite as bad as some people think. Most people work the usual 9am-5pm Monday to Friday routine and, as such, can only observe at weekends and on vacations, so they tend only to look at the sky then. That tends to give the impression that it's semi-permanently cloudy, as they are only looking through a small window of time so, statistically it's bound to give a skewed impression.
I am lucky though, in that I live in one of the clearest areas of Britain. The Isle of Wight, just off the south coast, has got one of the highest sunshine totals of anywhere in the country and this also means more clear nights. No, the UK isn't brilliant and we'd all like 300+ clear nights a year but you'd have to move to somewhere like Arizona for that - although I don't deny that if the opportunity presented itself I'd be off like a shot!

Friday, 25 March 2011

Thursday evening at the local astro society

The weather recently has been clear, but murky, and last night was no exception. I went to our local society's observatory last night (every Thursday is the open evening and we usually get a mix of members and sometimes interested members of the public) and we took out some scopes, including a 10" Orion Intelliscope.
Unfortunately the mist and murk were worse than the previous night and we only were able to look at the brightest Messiers. Galaxies, as expected, were worst hit and even normally good Messier galaxies were almost obliterated. We did look at M105, NGC 3384, M65 and M66 (NGC 3628, one of the Leo Triplet with M65 and 66, was utterly wiped out by the murk), M81, M82, open clusters M93 and M46 (not a bad view despite their low altitude in Puppis and the misty conditions), perennial faves M42 and M43, plus the attractive blue and yellow double star Iota Cancri and, later when it rose, Saturn, whose rings have opened up since I last saw it.

I have never used an Intelliscope before. The concept is similar to the Argo Navis system, a digital setting circle. You enter your wanted Messier or NGC number, the display shows some numbers, which are how far you need to push the scope in altitude and azimuth to get to where you are going, along with arrows showing which direction you need to push the scope. The numbers get lower the nearer you are and when you arrive at the location the display will read 0<>0 0<>0. The society's Intelliscope was a little off, with the objects being just out of the field of view, but not by much. It's a neat system and I'd like a similar thing for my scope, maybe an Argo Navis, one day.

Despite the crap conditions it was a nice evening and we also spent the time putting the world to rights as well as observing. It was disappointing though, that only a handful of us were outside, with most people choosing to sit inside the building and chat. It's an astronomy society, so it would be nice if everyone was outside but that seems to be the difference betwen UK and US amateurs. Over there, it seems to be a more vibrant and active scene.

Clocks go forward on Sunday morning. Yuck.

Thursday, 24 March 2011

Observing, 23rd March 2011

With the waning gibbous Moon not now rising until a minute after midnight (after one of the brightest full Moons in 20 years, thanks to it being at perigee), I hauled the 12" out for a galaxy-hunting session in Leo. We've had a nice run of lovely spring weather just recently, with lots of sunshine and some warmth, which makes a nice change after the coldest and cloudiest winter I can remember. Unfortunately, this has coincided with the rise of the Moon, so deep sky observing has been out of the question, but I've gone out several times with the binoculars for a general look round.

Date: 23rd March 2011
Conditions: Chilly (8C/46F), clear but murky; mist was coming down and making the skyglow worse. Very dewy indeed.
Transparency: III-IV (murk wiped out some of the fainter galaxies)
Seeing: II
NELM: Around 5.8
Equipment: 12" f/5 dob, 22mm Televue Panoptic (69x), 15mm Televue Plossl (101x), 8mm Televue Radian (190x)

NGC 3628, galaxy in Leo - Fairly large, low surface brightness but not too faint. Elongated east-west. Dust lane visible with averted vision. In the 8mm Radian (190x) it stretches across the field of view. One of the 'Leo Trio' with M65 and M66. 69x, 101x, 190x

NGC 3593, galaxy in Leo - Fairly faint, elongated E-W oval. Brightens to a non-stellar core. 69x, 190x

NGC 3379, galaxy in Leo - M105, one of the Messier objects in the H400. Very bright. Round with gradual brightening towards the centre. Makes an attractive pair with NGC 3384. Nice. 69x, 190x.

NGC 3384, galaxy in Leo - Next to M105 this isn't quite as bright and is slightly smaller. Brightens slightly towards its centre. 69x, 190x

NGC 3389, galaxy in Leo - Much fainter than 3379 and 3384. Elongated east-west. Featureless. Not easily seen at 69x, needs more magnification to be seen well. 69x, 101x, 190x

NGC 3379, 3384 and 3389 all fit into the same field of view at all powers (69x, 101x, 190x).

NGC 3377, galaxy in Leo - Bright oval. Oriented east-west. Bright, non-stellar core. 69x, 190x

NGC 3810, galaxy in Leo - Dim. Oval. Slightly brighter core. 69x, 190x.

NGC 3640, galaxy in Leo - Bright and round. Brightens gradually  to a non-stellar core. I looked for the tiny companion, NGC 3641, but only suspected I saw it. That will definitely have to wait for a less murky evening. 69x, 190x

NGC 3900, galaxy in Leo - Fairly bright. Oval, elongated north-south. Brightens gradually to core. 69x, 190x

I packed up at 2145 because it was getting mistier, murkier and generally yucky, causing lots of light scatter that you don't normally see here, and the galaxies were getting wiped out. This takes me up to 140 out of the 400 Herschel objects, which is 35% of the total. I still have five objects in Leo to do, so hopefully I can get these remaining ones within the next few weeks. I know that, in order to complete the H400, I am going to have to go further south, either to the Canary Islands or TSP again one year - but that is no hardship!

Here's the so-called 'supermoon' (which is what the media were calling it), one day after full, as it rose. I leaned out of an upstairs window, while handholding my Canon 7D and 400mm lens. It was low down and very golden. Even for a deep sky person it was a very attractive sight!

I haven't given up on sketching, it's because I want to get as much done of the Herschel 400 as possible so, for the time being, I am just finding things and doing written descriptions of them. I will go back to sketching as soon as possible.
I have got exciting news, but more on that soon...

Thursday, 10 March 2011

Observing 9th March 2011

Date: 9th March 2011
Conditions: Chilly, no wind at first but increased later on. Waxing crescent Moon was a bit of a nuisance and interfered slightly. Some drifting cloud
Seeing I
Transparency III-IV
Equipment: 12" Dob, 22mm Televue Panoptic (69x), 15mm Televue Plossl (101x)

NGC 2129, open cluster in Gemini - Totally dominated by 2 8th mag stars; the rest are much fainter (11th mag) plus some much fainter ones. At 69x it's hazy but is resolved at 101x. Bright, not scattered, quite compact. 69x, 101x

NGC 2266, open cluster in Gemini - Triangular haze with three slightly brighter stars in a line along SE side. One bright star at tip. Compressed, quite rich and partly resolved using averted vision at 101x. 69x, 101x

NGC 2304, open cluster in Gemini - Scattering of stars in semi-circle. There are 4 or 5 brighter stars with more scattered around. Fairly bright. 69x, 101x.

NGC 2355, open cluster in Gemini - Faint at 69x. Irregular. 69x shows dozens of faint stars on a misty background. At 101x the misty background has a vague S-shape. 69x, 101x.

NGC 2395, open cluster in Gemini - Irregular group of fairly bright stars plus fainter ones. Not rich. About 15 bright stars plus a couple of dozen or so fainter ones. Elongated N-S. 69x, 101x.

NGC 2420, open cluster in Gemini - Moderately faint patch. Rich, concentrated, fairly large. At 69x it's mostly unresolved mist but at 101x there are 14 or so brighter stars scattered across a background of unresolved stars. 69x, 101x.

Packed up at 2100 because the sky was getting murkier. I have now finished the H400 in Gemini, these were what was left over from last year.


Space shuttle Discovery returned to Earth for the last time yesterday. The shuttle program is nearly at an end, with only an Endeavour mission and a possible Atlantis mission, both to the ISS, left. It's a shame that, when Atlantis lands for the final time (if her mission gets approved), the shuttles will never fly in space again, instead finding themselves as museum pieces.

Monday, 7 March 2011

Observing 7th March 2011

Finally! After five months of endless cloud and the odd clear spell being around a gibbous or full Moon, I have actually managed to do some observing! It's been a totally cloudless day, a rarity in itself over this winter (which has been the cloudiest winter for 50 years, as well as one of the coldest), and the clouds stayed away as it got dark so I opened the shed and pulled out the scope. Everything seemed fine, the collimation was not too far out and the shed and silica gel had done their job of keeping the scope protected during some fierce winter storms and snow and the mirrors mould-free.

Date: 7th March 2011
Conditions: Chilly, cloudless, slight breeze with one or two stronger gusts that banged shed doors, no dew, no frost. That horrible light mentioned in my previous post has now gone!
Seeing: I
Transparency: II-III
NELM: 5.8-6.0
Equipment: 12" dob with 22mm Televue Panoptic (69x), 15mm Televue Plossl (101x), UHC, OIII filters.

I decided to knock off the remaining Herschel 400s I had left to do in Orion, left over from last year. The one failure was NGC 1788, no matter how much I searched, I couldn't find this little bugger. I think it had got too low.

NGC 2169, open cluster in Orion - This is an interesting cluster which looks like the number 37, upside down. The '7' is the westernmost part of the cluster. It has three bright stars and four fainter ones which make up the number 7.
The '3' is slightly larger and brighter than the '7', it also has three bright stars plus one slightly fainter one and six much fainter ones. There is a clear gap between the two components with no stars between them.. Very attractive. 69x, 101x

The sketch of 2169, below is not recent. It's a sketch I did some years ago but I thought I'd add it in to give an idea of what it looks like.

NGC 2194, open cluster in Orion - Easy to find. Quite faint but rich. There are a few quite faint, but distinct, stars in front of many, many fainter ones. Partly resolved. Detached - stands out well despite faintness. 69x, 101x

NGC 2186, open cluster in Orion - Awkward to find, especially as it's not shown on my Sky Atlas 2000.0 so I had to come back to the house and print off a MegaStar chart with telrad circles on it. Not easy with one eye tightly shut to preserve its night vision! Located within a triangle of bright stars, which points east. Faint. Poor. Not concentrated. 69x.

Hunted for NGC 1788. Got annoyed with it and gave up as I just could *not* locate the thing, so I moved on.

NGC 1999, reflection nebula in Orion - This was easy to find, as it is located just south of the Orion's Sword complex. Small, round and bright. Fuzzy with brighter middle. UHC does not improve the view much if any while OIII is totally useless. 69x, 101x, UHC, OIII.

It was a short session, slightly under a couple of hours. I'd inevitably forgotten a few items, such as printing off MegaStar charts and other bits I had to return to the house for, but it was a good session and I'm pleased. It's nice to be back, although I'd not been idle because I'd done a lot of birding (my other interest) over the winter. The Moon's on the rise again so, after this coming weekend, it might be a while before my next session. And I managed to avoid trampling the daffodils too badly in my observing patch, there were casualties but only one or two.

This is the sort of weather we've had over the winter (observing shed is the grey one in the background). Cloud, cold and more snow than usual.

I never did get to the Isle of Wight Star Party this year. I intended to, but caught a bad cold so, deciding that I would not be thanked for sharing (as well as not feeling like standing around in the dark with it) I didn't go.