Thursday, 15 April 2010

Volcanic sunset

Here in the UK, the big news of the day (discounting the, frankly boring, General Election and the various political parties trying to outdo each other with the various packs of lies and promises they have no intention of keeping) is the huge cloud of volcanic ash that has covered the country, and most of Europe, from Eyjafjallajökull volcano in south west Iceland, which is currently erupting. The eruption has grounded all flights into and out of the UK and most of Europe and this is set to continue into the weekend.
However, with the ash covering the UK, it has provided the potential for decent sunsets. This evening's sunset was a little redder and darker than usual.

More practically, I sincerely hope the eruption has died down, or the eruptive material is blowing away from us, in three weeks' time, as I will not be best pleased if my flight to the US is disrupted or cancelled. The trouble is, with nature, you never know

Observing 14th April 2010

Seeing II
Transparency III-IV - pretty 'milky' with some light scatter
Still, with no wind., although the slightest of breezes sprang up later.
Instrument: 12 inch f5 Dobsonian, 22mm Televue Panoptic (69x), 15mm Televue Plossl (101x), 8mm Televue Radian (190x), Lumicon OIII filter.

As the skies were really murky, and Virgo was washed out by the murk and a lot of light scatter in that direction, I decided to go to Draco for the Herschel 400 objects (and others) there instead. Things were a little awkward as Ursa Major was upside down and the charts difficult to relate to the sky without turning them upside down.

NGC 5866: Bright, fairly small. Elongated n-s, brightens gradually towards a diffuse centre. Bright star on one end and a slightly dimmer star on western edge. Dust lane? 190x

NGC 5907: Very thin, edge-on galaxy. Not much of a nuclear bulge, if any. Fairly faint, elongated n-s, quite large, stretching across field of view at 101x. 69x, 101x

NGC 5985: Very small and bright. Oval. Bright core, elongated n-s. 190x

NGC 5982: Very large oval galaxy, evenly bright, no brightening to middle. Slightly elongated, not face on. Looks like smudge or thumbprint. Very faint, not much brighter than background sky. 190x.

NGC 6543: Very bright and blue planetary nebula, even without the OIII filter. This was fairly easy to find, although at first I thought it would be too low, as the stars I was using to hop to it weren't that far above the trees in next door's garden. The OIII filter really brings it out. Small and round. Slightly fuzzy and definitely non-stellar at 69x.
At 190x it is uniformly bright with the middle being no brighter than the surrounding halo. No darkening anywhere within the nebula. 69x, 190x, OIII filter.

NGC 3147: This took a bit of finding, I had to star hop to it, using galaxies, rather than stars. I began with the easy to find M81/82 and went from there. 
Bright, round, with bright nucleus. 190x.

Because of work the next morning, I packed up at midnight BST. For a short session, it was a pretty good one, and I don't have to return to Draco for any Herschel 400 objects.

Observing April 11th and 12th 2010

At last! A clear night - or was it? It certainly began promisingly enough with the skies clearing off so I set up just before sunset in the hope that I'd get some observing done.
Unfortunately this state of affairs didn't last long and after the session began drifting clouds appeared and, as if in a devious conspiracy, they sat right where I aimed my scope. It seemed that when I moved to a different part of the sky they followed!
However, despite this, I managed to see the grand total of three objects on my H400 list.

Chilly +4C
Seeing III, Trans IV - Drifting clouds interfereing with observing, plus some high cirrus stuff
NELM 6.0
Instrument: 12 inch f5 Dobsonian; 22mm Televue Panoptic (69x), 15mm Televue Plossl (101x), 8mm Televue Radian (190x), Lumicon OIII filter

NGC 2392 - planetary nebula in Gemini: Easy to find. At 69x it's round, fuzzy with bright middle. It's a greenish-blue colour. OIII brings it out well. At 190x it looks very fuzzy with a very bright centre and a dark area between outer parts and centre. 69x, 190x OIII

NGC 2420 - open cluster in Gemini: Nice, fairly small o.c. Very rich and moderately bright. Irregular shape with c. 30 bright stars on a nebulous background which is many many unresolved stars. The brighter stars are all the same, or similar, brightnesses. 69x, 101x

NGC 5194 and NGC 5195 - galaxies in Canes Venatici: Fantastic. NGC 5194 (aka M51) is a large, face-on spiral. Spiral structure is easily seen and it has a big, bright nucleus.
The companion, NGC 5195, is much smaller. Round with a halo surrounding a bright core. 69x, 101x.

At this point, the clouds were becoming more than just an irritation, they were becoming a damned nuisance, so I packed in. As I came back outside to pick up the scope base, the clouds had filled the sky.


The following night, 12th April, wasn't totally clear, so I didn't even bother carrying the scope out but, instead, decided to bag Melotte 111, the Coma Star Cluster, with my 8x42 binoculars. Mel 111 is on the AL Binocular Deep Sky list, which, apart from four objects in Cepheus and Lacerta, I have just about finished.
Easily seen with the naked eye, this huge open cluster is pretty spectacular in binoculars. It is harp-shaped, with 15 bright stars outlining the shape of the harp. There are many more fainter stars in among the brighter ones. The stars are all blue-white and the brightest ones all the same magnitude. Nice.

Sunday, 11 April 2010

Forecasters' idea of a 'clear sky' vs my idea of a clear sky!

Just recently, I have got more than a little annoyed and frustrated with the weather forecasters' less-than-accurate definition of "clear skies". To me, as to any other amateur astronomer, a clear sky DOES NOT mean murk, high cloud and other general crap obscuring the view of all but the brightest stars and planets. I am so fed up with reading on the forecasters' web sites (including the BBC) and hearing and seeing the weather bulletins on TV and radio promising "clear skies" only for it to be haze and murk with only a few bloated, bright stars and planets visible and all but the very brightest star clusters wiped out.
Okay, I understand that Joe and Jane Public don't give a toss about astronomy and that, as long as shadows are cast during the day and they see the odd star or two or the Moon (when around) at night then, to them, that constitutes "clear" but, can we have a bit more accuracy in the forecasting please? If it's going to be hazy, tell us. Don't fib and say it's going to be clear when there's actually going to be a load of high thin cloud around.
Yes, we do get contrails from jets passing overhead, but these dissapate quite quickly and the high thin rubbish is not all contrails in any case.

To this end, I have emailed the Mess Met Office. It most likely won't change anything but it's always good to let these sort of organisations know that people are taking notice of what they do and say and, if it's inaccurate, then they should know.

"I am an amateur astronomer and I am increasingly annoyed and frustrated, as are other amateurs, by the forecasters' definition of "clear skies". To us "clear skies" do not mean high haze and murk with only a few bright stars visible as this is NOT clear and is totally useless for doing any astronomy.  Can we please have forecasts which more accurately reflect this and not misleading (from an astronomical point of view) ones that do not take into account high thin clouds? Several times recently clear skies have been forecast, only for those so-called "clear skies" to turn out to be murk and high cloud - and on checking the on-line forecast it still says "clear skies" when it obviously isn't!

I understand that the forecasts are aimed at the general public, a lot of whom consider a bit of hazy sunshine or a few bright, bloated stars and a murky Moon to be "clear" and who have no interest in, or understanding of, astronomy, but amateur astronomers are also members of the public and we'd like more accurate forecasts, please, taking into account haze and high thin clouds.

It'll be interesting to see what sort of a reply I get - if, indeed, I get one.

Friday, 9 April 2010

Observing, April 8th 2010

The first clear night in April so far that I was able to observe. While I am a deep sky observer, I do like to look at the planets now and then and it would be a shame to ignore Mercury when it is favourably placed as it is at present. Both Venus and Mercury are low in the western sky just after sunset and, through my birdwatching spotting scope, I saw Mercury as a disk. I also took a couple of - bad - photos with my Canon 40D and 400mm lens, one of which is this one. I labeled it as Mercury doesn't show up that well (click for larger picture):

By the time I'd finished messing around with planets and finished setting up the scope and gathering all the observing bits and pieces together it was time to observe. Unfortunately it wasn't as clear as it promised, with a very thin haze which scattered light around, making the naked eye limiting magnitude a very poor 5.8 to 6.0.

Clear, but with a very high thin haze.
Cool: +6C, down to +2C later.
Very slight breeze now and then
Seeing: Ant II; Transparency: III
NELM: 5.8 to 6.0 due to light scatter caused by haze - poor for here.
Instrument: 12 inch f5 Dob, 22mm Televue Panoptic (69x), 15mm Televue Plossl (101x), 11mm Televue Plossl (138x), conditions not good enough for higher magnifications.

I spent most of the session in and around Ursa Major which is rich in galaxies but no so rich that you're overwhelmed by sheer numbers of the things, which is the case once you get into Virgo and Coma B. All these observations are of galaxies.

NGC 3613 UMa: roundish, fainter than 3619 (which is in same f.o.v at 69x) with a much fainter core. Well defined against the sky.

NGC 3619 UMa: Bright, oval, small. Well defined. Bright core.

NGC 3610 UMa: Small, bright and round. Bright core.

NGC 3556 (M108) UMa: Yep, a Messier, but this has shown up on the H400 list, so here it is - Large, almost edge-on. Can see dust lane. Star superimposed on top of galaxy; it looks like a stellar core, but isn't.

NGC 3982 UMa: Not quite round. Bright. Bright core surrounded by halo.

NGC 3972 UMa. In same field of view as 3982, but much fainter. Elongated. brightens somewhat towards centre.

NGC 3998 UMa: Much larger than previous two galaxies. Round with some brightening towards centre.

NGC 3992 (M109) UMa: Large, oval and featureless. Uniformly bright with three foreground stars superimposed on it. Quite boring, really.

NGC 3953 UMa: This one is very nice. It is large, elongated north-south and is bright. It also has a large nucleus which is brighter than the surrounding galaxy.

NGC 4026 UMa: Bright, elongated NE-SW. Lovely edge-on spiral with a very bright nuclear bulge.

NGC 3729 and NGC 3718 UMa: These make a nice pair. Both are oval and pretty faint, although easy to find. Both are uniformly bright with no hint of a nucleus. 3729 is the larger one of the two galaxies. Hickson 56 is nearby but the crap hazy conditions made this invisible.

NGC 3631 UMa: Round with bright compact core. Pretty large and pretty bright. Bit of a bugger to find though, due to its location out on its own, just below the Dipper bowl. Hint of spiral structure with averted vision.

NGC 4565 Com: A perennial favourite! This is an edge-on spiral and is spectacular to look at. At 138x it stretches right across the field of view. Very bright with very bright nuclear bulge and a very prominent dust lane which cuts it in two.

NGC 4494 Com: Near 4565 this is another bright galaxy. Round with bright core.

NGC 4448 Com: Located just off the apex of Mel 111 (the Coma Berenices Star Cluster) this is a bright not-quite-edge-on galaxy. Nice bright compact core. Elongated east-west.

NGC 4559 Com: Large spindle-shaped even glow. Well defined against background sky.

NGC 4278 Com: In same f.o.v at 69x as NGC 4283. One is elongated and brightens towards its centre and the other is smaller, brighter, rounder and has a more compact core.

NGC 4274 Com: Bright oval. Almost edge on. Brighter middle.

By this time it was getting late, thanks to that thief of observing time BST. As I had to be up at 6am for work, it was time to pack up and head in.

At the Isle of Wight Star Party back last month, Owen Brazell was selling off a few spare eyepieces, which he'd replaced with Televue Ethoses and I bought a very nice 22mm Panoptic from him, which has now become my main 'searching' eyepiece. The barrel is scratched but the e.p. is in otherwise excellent condition and it has replaced the 20mm and 25mm Televue Plossls in my collection - now I have two redundant eyepieces!

Monday, 5 April 2010


All this afternoon it has been looking good for a clear evening. Until just now when it clouded over - the satellite pic does not look good either, with the system out to the west turning round and dragging crap up from France. How annoying.

Above: Satellite image, from, showing the crud moving up from the south/south-west. There's a clear spot to the south west, but that, unfortunately, will miss us. The latest view shows it filling in, in any case.

Below: The view from the garden, looking south west, and an upstairs window, also looking south west, aren't any better.

It might clear off in the early hours but as I have to be at work tomorrow morning, that's not a lot of good. Hopefully, it'll be better later in the week. I have only managed five observing sessions since January, so this is all a bit depressing, especially as I want to get among the spring galaxies before the days lengthen so much that observing will become awkward. I think I'd like to emigrate to a clearer climate at a lower latitude. I'm glad winter's over but I hate the light nights.