Category Archives: Double Stars

The 18 inch gets to see the sky

The 18 inch finally got its first look at the sky, as it cleared just before sunset after a day of thundery showers, some of which were torrential. The forecast called for a clear night so I hoped to get at least an hour in. I put the scope together, which at least is getting easier and waited – impatiently it has to be said! – for darkness. Collimation was a breeze as, despite the scope being loaded into a van, driven along 200 miles of motorway network, carried on a ship across a bumpy Solent, driven across the appalling goat tracks that pass for roads on the Isle of Wight, unloaded from the van and bumped across the cratered and uneven back lawn, it was not that far out and even if it had been, the large bolts make it a joy to do and not a boring chore. It took 30 seconds to line up the secondary and then the primary – it was FAR easier than either my 12 inch or my 8″ scopes.

I did discover a slight Telrad fail – I’ve put the base in the wrong position. It’s not a big problem but I could have done with putting it next to the finder. I’ll move it at some point, and I’d like to screw the base to the UTA, rather than have it fixed by means of the adhesive base, but it’s going to be ‘fun’ getting it off to move it. It’s not a big deal, it just means that I have to walk round the scope to the eyepiece once I have located something.

When it got dark, the Milky Way was as good as I have ever seen it, with the Cygnus rift very striking and the rest iridescent. It was very prominent right down into Sagittarius. I forgot the SQM, but the naked eye limiting magnitude was at least 6.2.
The neighbours’ lights were annoying as usual, and I wish they’d adjust their insecurity light as it blitzes everything. Luckily that only seems to be put on when their dogs are out having their late night piddle. I wish they’d move away and a nice elderly couple who go to bed at 8.30 and who don’t have all the house lights on would move in instead!

Date: 18th September 2011
Conditions: Clear at first, clouds moving in later. Very dewy (88% humidity) and wet underfoot.
Seeing: II
Transparency: II-III; IV later when clouds arrived.
NELM: ~6.2
Equipment: 18″ f/4.3 Dob, with 22mm Televue Panoptic (90x), 8mm Televue Radian (247x)

First up, as it wasn’t dark and I was just itching to look at something, was the Alcor-Mizar system.Very nice at 90x, with the jewels blazing brightly. As this is an f/4.3 mirror it was evident that I need a coma corrector, such as a Paracorr but I can live with it for now.
I didn’t take any notes, beyond writing names down, either; this wasn’t a ‘serious session’, it was more a case of getting used to the scope and to the ladder I needed to use with it, rather than a proper serious observing session.

NGC 7006, globular cluster in Delphinus – I’ve seen this on quite a few occasions but never as good as this, and this was with the sky still dark blue. At 247x, it was resolved and the core was very dense. 90x, 247x

NGC 7331, galaxy in Pegasus – This was the best ever view, the galaxy appeared very large and bright, with a bright tiny core. Elongated north-south. 90x, 247x.

I also viewed NGC 7337, NGC 7335, NGC 7336, NGC 7340 and MCG+6-49-44, the ‘Fleas’ in the Deerlick group. The fainter Fleas were quite hard with my 12″ but are easy in the 18″. NGC 7336 was pretty faint and the faintest of the group. 247x

The scope is a bit stiff to move, although not hugely so and I expect the stiffness will wear off in time. Besides, it’s better for it to be slightly too stiff than too easily moved.

I packed up at 2130 just before the moon rose as the clouds had returned (contrary to the weather forecast!). I took the scope to bits and returned it to the shed, after carefully drying it off. The shroud was wet through and that’s now hanging over the landing rail to dry.

In unrelated news, I have decided to get another car. My Citroen is getting a bit old and I’ve never really liked the thing as it’s too small, feels ‘cheap’ and is easily ‘bullied’ off the road, so I have traded it in for a Renault estate. Hopefully I can pick the new one up on the 24th. It has an added bonus in that the big telescope will fit into it, as I decided on the spur of the moment to change my car, I thought I may as well get a bigger one while I was at it. The only downside is that the tax will cost more and it will also cost more to run.

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.

Double vision

On Tuesday (11th August) we FINALLY got a clear night. Well, clearish, as the haze was bad but it was certainly better than the near 100% cloud cover we’ve been getting recently.

Because of the murk and the rising waning gibbous Moon, I decided to stick with a few doubles in Bootes, plus some ‘lollipop’ bright objects elsewhere in the sky. It was also a short session as it was gone 11pm and I had to be up for work the next morning.

My observing notes read as follows:
A rare clear night this summer – July and August have been frankly bloody awful with only a couple of clear nights for observing, including tonight.

The transparency tonight is not good and I am only using a small refractor (my 12″ is out of action, and likely to remain so for a while or until I get a new one), so concentrating mostly on double stars. After having been out here a while, the sky conditions are not good. It’s milky and there’s very little contrast in the Milky Way with some high thin cloud and the waning gibbous Moon interfereing.

Alcor and Mizar in Ursa Major:
One of my favourite doubles, this well-known system is a lovely white pair, visible to the unaided eye but superb through the small refractor at 37.5x

Albireo (B Cygni):
My favourite double, the bright gold star and it’s slightly fainter, bright blue companion are stunning.

Delta Bootis:
Faintish gold star with faint blue companion. Wide double. Nice.

Unfortunately only a short session, due to having to go to work tomorrow. I’ll be glad when the long nights are here and BST is back to as it should be, GMT.

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Have decided to go for a 12″ Lightbridge or Revelation. I had decided on the LB, but my work contract finishes two weeks earlier than planned, so I might go for the cheaper Revelation instead. However, I was pretty annoyed to hear that the Revelation has now gone up from £549 to £660 in the past week. Bugger!