Mag x423, Y Shadow, Unexpected Company

[cloudsweeper]

Friday evening - second session, this time with the 10" Dob.  Moon (3 days from full) had emerged this time - couldn't resist.  

I concentrated on the region with Schickard, Nasmyth, and Phocylides.

Mag - from x144 to x423 - sharpness still good at x423, but a bit duller.  Also tracking harder, and 'scope wobble an issue.  But x212 and x254 were perfect - focus less critical, stable and steady view.

The floor of Schickard is clearer than those of Nasmyth and Phocylides, and its many large and small craters showed up well.

What caught my eye however was a distinct Y shadow where Nasmyth abuts Phocylides.  It extended the full length of where they join, and since Nasmyth has a diameter of about 78km, that gives an idea of its scale.  I can only imagine there must be a high peak at the centre of the Y.  Anyone know for sure?  I attach a pretty basic sketch to illustrate.

As for unexpected company, near the end of the session I heard a couple honks and looked up to see two ghostly swans, flying low, and directly overhead.  (I've had for company owls, geese, hedgehogs, and bats - never swans!)

Doug.

Edited November 28, 2020 by cloudsweeper

[maw lod qan]

Excellent post! Sharing the night with nature is so wonderful.

Dont get any hedgehogs, or geese, but bats, owls, coyotes and foxes are seem or heard often.

[Stu]

Lovely stuff Doug.

Not sure if these help, from the MoonGlobe HD app.

It certainly looks like there is some higher relief in that area.