Orion Doubles, Lunar Dome Too As A Bonus!

[cloudsweeper]

6.55pm, waxing gibbous Moon, clear sky - put the 8SE into action for a change, for the ease of GoTo and the joy of targets being tracked.  I aligned on Betelgeuse only, since I was operating in that area, so GoTo was likely to get me right on targets.  And so it was.

Sigma 729 / 33 Ori - a close match, 1.9" separation.  Using the SAO number put me on target.  At x169 the pair was just separated, and AV helped.  At x185 - less clear, also a bit wobbly.

Sigma 712 - 3.2" - the faint companion was just discernible at x 102; better at x145.

Sigma 654 / 17 Ori - triple, but visual double, 6.8".  The faint companion was easily spotted at x145; the primary appeared yellowish.

And now the highlight.....a lovely spectacle:

Sigma Ori / 48 Ori - a very popular multiple, actually a septuple system, but a visual quadruple.  At x68, the bright A/B star stood out, with the D and E stars at 13" and 41".  In distance terms, the E star is about 0.25ly from the primary, which is about 15 or 16,000 AU!  The faint C star (11" sepn.) was close to the primary, on the opposite side, but it was clearly seen, especially with AV.  

And in the same FOV - 

Sigma 761 - a little west of the above - a triple, comprising a pair at 9", and an outlyer at 68", forming a sharp arrowhead pattern with three stars of similar magnitudes.  Also very clear at x68.  x102 also good.  

(I also tried for 32 Ori and 52 Ori - separations 1.4" and 1.2" - I had to hop from Bellatrix and Betelgeuse, as the SAO numbers of the targets were not in the handset.  But the seeing was against splitting these close binaries, and at x169, 185, things were a bit wobbly too.  Perhaps also the lack of sharpness from the 'scope - esp. with brighter stars - might have been a factor here?)

The Moon was blindingly bright at x68, so I quickly went up to x102 with a polarising filter attached (briefly), and examined the region near the terminator.  From Copernicus, crater Hortensius was found in Mare Insularum, but the six domes (small, flat topped volcanoes) to the north could not be detected, even up to x203.  However, the larger Milichius Pi Dome, NW of Hortensius, and west of Milichius itself, was noticed at x145.  It stood out as a small circular patch with a subtle change of shade relative to the surroundings.

After a final more general view at the lower mag of x102 (revealing beautiful clarity and detail), I ended the session after 1 hour and 40 minutes, having achieved most of the goals I had set.  Very rewarding indeed!

Doug.

 

[des anderson]

That`s a great report and your descriptions of the double stars was just great. Des

[Astro Imp]

A great report of what was obviously a very  enjoyable and rewarding session. 
I didn't take the opportunity of going out last night, stayed in and watched the footie and when the match was over the cloud had arrived.

 

[Paz]

Great report, I've plagiarised a couple of objects for my target list.

[Stu]

Lovely stuff Doug, a very productive session. Sigma Orionis is a corker isn't it  especially with that triple above it.

I've caught 52 and 32 Orionis in the Mewlon recently, I would think the should be within reach with a well cooled scope and good seeing.

 

[cloudsweeper]

58 minutes ago, Stu said:

Lovely stuff Doug, a very productive session. Sigma Orionis is a corker isn't it  especially with that triple above it.

I've caught 52 and 32 Orionis in the Mewlon recently, I would think the should be within reach with a well cooled scope and good seeing.

 

Yes Stu, I was very satisfied indeed, especially after not being out for 10 days!  (Still had 29 sessions this year, mind you.)  I'll try 32 and 52 Ori again - might do better with the Dob, or even the 120 frac.  I did wonder if the Cat's lack of sharpness (esp. with bright stars and the resulting glare/scatter) might be an issue - although I did enjoy the GoTo and the tracking.  I had grown used to going to the Dobhouse to make notes and change EPs, then return to find the target had moved out of view!  

Doug.

[Stu]

Yes, tracking is nice, I'm enjoying similar aspects of the Mewlon/GP-DX

[chiltonstar]

If you have any luck with 32 and 52 Orionis, try 42 Ori as well. It's quite a challenge, but doable with my 180 mak, so probably your scopes as well.

Chris