Observing 15/09 - in surprisingly good seeing

[lunator]

Despite having a week off the weather has been pretty poor here in Bucks. There was some hope for clear skies and I was planning to get a quick look at RS Ophiuchi and the novae in Cassiopeia.

It was looking good around 8.30pm so grabbed my ‘grab and  go’ set up of ST80 on the heavy duty photo tripod.                                             

The 1st stop was the Moon low on South in between the houses.  Starting with the 25mm ortho giving x16and then using the 12.5mm(x32). The moon fitted comfortably in the field of view with clear detail. This gave me my first indication the seeing was good. I particularly liked the view of the Clavius crater. I  could see some of the interior craters so I pushed the magnification to x100 (4mm ortho) and the smaller craters were very clearly visible within clavius.

RS Ophiuchi
Dropped back  to the 25mm (x16), first impression – no colour.
Used the 12.5mm to darken the sky background a little more.
It is quite faint now. 
Fainter than HD162488 (7.98)
Similar in brightness to HD162215 (9.68) & HD162369 (9.56)
Brighter than HD162449 (9.81)
I estimated the Magnitude at 9.6.

My 2nd Novae of the night was the novae in Cassiopeia. Just used the 25mm.
Nova Cass is still quite bright. It looked reddish-orange to me.
It was fainter than bright star HD220819 (6.61)
Similar to HD220057 (6.94)
Brighter than HD220770 (7.82) star and much brighter than SAO20610 (8.97)
I estimated the magnitude to be about 7.

Saturn had cleared the houses and with the conditions I decided to push the magnification to maximum available using the 4mm ortho. (x100). For the first time I spotted the band on the surface (this is easy in my large scopes) and I am certain I could see the Cassini division.  

I moved onto Jupiter and very quickly decided to stay with the 4mm. I could clearly see multiple belts with details on their edges. Seeing all the belts and not just the equatorial ones was a very pleasant surprise. The 4 moons were strung out 2 either side. 
This was the best view of Jupiter I had had in a small scope. 

With the good seeing I decided to have a go at Pi Aqilae.
It would be tricky in the ST80 with a separation of 1.4” and a delta M of 0.41
The ST80 Raleigh criteria of 1.725” and a Dawes limit of 1.45”
In my experience for bright close pairs even at the Dawes limit you can detect the companion if it is with 2 magnitudes of the primary. I was able to see an elongated star and when checked against WDs it was in the right quadrant. Overall i was quite pleased with the result.