Some Shadow!

[cloudsweeper]

28/1, after 3.30am - very clear, not as windy as yesterday - so set up the ED80 Apo again.  The Moon (waning, just past third quarter) was low in the SE.  Cassini (which I viewed closely yesterday) was right on the terminator, and just west in Mare Imbrium was a most interesting sight, namely the small Mons Piton, casting a very long, thin, and pointed shadow back towards Cassini, giving an indication of Piton's shape.  The mountain and shadow together were about the size of Cassini itself.  At x80 the view was very sharp and detailed, with only a slight shimmer, and that did not detract from the clarity.  Still OK at x120, less so at x160.  I returned to this area well over an hour later at 5.10, and the shadow had almost reached Cassini.  Since Cassini has a diameter of about 56km, I estimated that the shadow of Mons Piton exceeded that figure - a shadow more than 34 miles long.  The view seemed steadier; clarity and detail were excellent, even now up to x160, at which mag the Moon's movement in the eyepiece was very obvious.

I wanted to check how this new 'scope did with doubles, so Lyra's Double Double was the next target.  It was easily found at x20/4.1deg, as two unsplit specks.  Same at x60.  At x120, those specks became two fairly matched pairs running in perpendicular directions.  Both separations are about 2.3", so the 'scope performed well in showing all components as nice sharp points with a very clear split.  At x160 however, only one pair was resolved and clarity decreased on account of the seeing no doubt.

I did try for a few fuzzies, but the combination of smallish aperture and a bright Moon meant no success there, and after 1.75 hours I ended a very enjoyable session. 

Doug.

[Alan White]

There is a 3:30 AM! A time I spend with my head on pillow, admire you dedication.

That little 80mm is sounding rather good.

[Astro Imp]

Interesting report Doug.
Carrying on from your post yesterday when you mention ten sessions already this year I can see how you manage this now. I'm afraid I'm with @Alan White, 3.30am is sleep time!!!

[cloudsweeper]

1 hour ago, Astro Imp said:

Interesting report Doug.
Carrying on from your post yesterday when you mention ten sessions already this year I can see how you manage this now. I'm afraid I'm with @Alan White, 3.30am is sleep time!!!

Darn it, I've been rumbled!  ?

Doug.

[domstar]

Great report. I really like the details about the moon. I've never considered the size of the shadows before. That's phenomenal. 

I'm with the others- maybe we should have a whip-round and get you a comfy pair of pyjamas.

[cloudsweeper]

1 hour ago, domstar said:

Great report. I really like the details about the moon. I've never considered the size of the shadows before. That's phenomenal. 

I'm with the others- maybe we should have a whip-round and get you a comfy pair of pyjamas.

Thanks Dom.  I too had  not given shadows much thought,  but this one was so well shaped, and close to a crater of known size that the comparison was quite easy.  

3.30?  It was actually my wife who pointed out the clear sky.  I suspect she was trying to get rid of me.  ?

Doug.

[cloudsweeper]

2 hours ago, domstar said:

Great report. I really like the details about the moon. I've never considered the size of the shadows before. That's phenomenal. 

I'm with the others- maybe we should have a whip-round and get you a comfy pair of pyjamas.

Comfy pyjamas?  Go ahead!  That way, I can get up and go straight out.  Thanks for the kind thought!  ?

Doug.