Club night report

[GavStar]

Despite the light evening, we had a really fun club observing session last night. Being nice and warm also helped (but not the midges that were out earlier on)

We had four scopes out (a 10" dob, a nice large Ritchey Chretien, Stu's Tak FC-100DC, and for the first time at the club my TEC140) and there was also an imager so a varied mix.

Started at around 9pm finding Jupiter in the light skies. Immediate nice views with a big festoon in the NEB and three roundish white objects in the SEB. This tallied up nicely with Neil's image posted last night. Great views in all three scopes, with the Tak showing all the features that the TEC showed. The RC showed an excellent live feed of Jupiter with lots of detail through the attached camera.

Eventually stars started appearing, and my first target was the double double, a current favourite. A clear split in the TEC but I personally preferred the view the Tak showed, the stars seemed just a shade crisper to me, maybe it was the magnification or the eyepieces being used? Next was M13, which is where the TEC started to show the aperture advantage. Nice granular view at around 90x.

The highlight for many of us then followed which was surprisingly for me M5. It took magnification really well and at 200x showed both the inner core clearly and a beautiful sprinkling of stars around it particularly to the bottom left.

Stu decided to instigate a few double star challenges. First off was I think Epsilon Bootis (Izar), which at 200x showed clear split of the much fainter second star. At this stage I got out the 4mm delite for 250x and the extra magnification definitely helped. We had a quick look at Porrima. Then Stu got us looking at one whose name I can't recall (Stu?) where the split was very tricky. We managed to convince ourselves that we did see the second star at 5 o'clock but it was not conclusive.

By this time Saturn was rising. Initial views when it was at 7 degrees high were horrible, lots of CA and unstable viewing. However, later when it was higher, the rings were much clearer and we saw 3 moons (plus one rogue star pretending to be a moon).

Finally I had a quick look at one of my favourite doubles, Albireo, which in the 4mm delite took up most of the fov of the eyepiece - a clear split  The blue and gold of the two stars always excite me. We packed up around 12.45am.

So despite the skies being quite light, a very pleasant time and it showed me that there was plenty to look at even in not that dark skies. (Lesson for next time is to bring mosquito repellent...) Many thanks to Peter for his help using the E-Bomb (ethos 21mm) to find several objects over the course of the evening.

[David Levi]

Nice report. I observed M5 (again) last night - at 200x magnification as well. It is a beautiful globular cluster.

Apart from having to stay up late or go to bed and then get up I like these warm observing nights - so comfortable and relaxed.

[GavStar]

Just remembered we also had great views of the ring nebula which took magnification well and had good definition with largish scale. I prefer the views of the ring to the dumbbell - more distinctive imo. 

Jupiter was a bit bright at times so I should have tried my baader moon and sky glow (annoying I forgot to do that)

 I'm sure there's other things I've missed as well. Quite a long night...

[Stu]

3 hours ago, Gavster said:

Then Stu got us looking at one whose name I can't recall (Stu?) where the split was very tricky.

Nice report Gavin, it was a fun night.

The tricky one was Zeta Herculis, my nemesis in that I've never managed to split it. I would agree that there was definitely something visible last night, not something I would say was conclusive but closer than I've ever managed before. Perhaps now I know what I'm looking for it might become easier.

M5 was a cracker in your TEC, as was Jupiter  

[GavStar]

Thanks Stu. I've had a quick look into Zeta Herculis (you've got me hooked now!). From the information I've found, it seems that the separation of this double star is 1.3". Apparently the first diffraction ring of the primary for a 140mm scope is also around 1.3" which makes it even more difficult to spot the companion star. It should show as a little spot that disrupts the diffraction ring and I think that's a very accurate description of what we saw last night. With a 130mm scope the companion should sit on the edge of the first diffraction ring making it easier to see. Sounds like a job for my AP130GTX!! I think I'm going to get my 3.5mm eyepiece out of mothballs for this task to get 235x magnification. EDIT from further reading to make this double obvious it's suggested to use up to 500x. Gulp! Powermating my 4mm eyepiece may be needed....

I'd be interested in hearing other people's success (or not) stories with this double and what they used to see it?

 

[PeterW]

You guys always end up staying and seeing more good stuff! We also managed M64 and M51 in the 12" RCX, but edge of visibility stuff as it wasn't even properly dark. The 2degree field of view helps when it comes to finding stuff. Pity next months meetihg will be even lighter :-( 

great session

PeterW

[John]

Great report Gavin. Some nice scopes being used too

It was a lovely night for doubles last night. Zeta Herc was clearly two stars but very close together with my TMB / LZOS at 300x. A little clearer at 480x (!). The secondary star is at about 5:00 pm with a frac and looks sort of dirty blu tack coloured to me (ie: greyish !). The secondary does sit more or less on the 1st diffraction ring with my 130mm. The diffraction ring with that scope is very thin so not too obstructing.

I reckon yoiu got it !