surprise night

Yesterday afternoon Clear Sky Clock showed it would be clear.  But it is notoriously wrong for high thin clouds or fog conditions, which is what I saw upon arriving home last night.  The GEOS satellite I also checked didn't look promising, with a river of water vapor pouring in to the Bay Area.  So I didn't set up.  But, after dark, it was clear.  I've noticed how many times thin clouds will dissipate after nightfall; it must have something to do with the air temperature changing?  In any case, I set the 8-inch up and had a nice surprise night.

After poking around Orion for a while -- which is sinking soon after darkness now -- catching E-F in the Trapezium, I went after some Carbon Stars.  The seeing was average but the transparency was below average -- the sky lit up with haze from the rising full moon.  I barely made out what I thought was Alpha Hydrae; after confirming the field on the chart I made a long hop down to:

Gamma Hydrae: red in the finder, magnitude 8-9, sharply orange-to-red, brightest in a sparse field.  Though already evolved into a carbon star, it is younger than the sun, having started life with a higher mass it burned through more quickly. 

My next target, U Hydrae, was behind our neighbor's large pine tree, so I spent some time looking at Jupiter instead.  No transit events or GRS, but dark barges in the EBs and some darkening in the northern pole region. 

Back then to U Hydrae, which was red in the finder, and a bright orange in the scope, about 7th magnitude, with a faint but pretty double to the south at the edge of the field.  AAVSO pegs the magnitude at 5.5; I've never been good at estimating magnitudes but the poor transparency surely played a role in dimming what I saw. 

V Hydrae needed some more waiting to clear a branch, and when it did it was a nice deep red color, a tad orange, magnitude 8 (AAVSO says 9).  It has a B-V color index of +5.5 and is one of the reddest stars visible.

My last target was VY Ursae Majoris, but this was blocked by my own roof, so I spent time on the moon.  While it was supposed to be full I did notice some terminator way at the edge, and enjoyed a variety of interesting sights.  Slivers of light off the edge of the moon which, as time passed, grew extensions and arcs and became crater rims.  Ridges folded like an unmade bed.  Shadows of ridges on further mountains behind.  Copernicus was flat and spread its Medusa hair widely over the lunar surface.  At one point a bat flew in front of the moon -- it was small, and it took three or four seconds for it to make its jangled flight across.  It must've been half the neighborhood away.

I tried for VY Ursae Majoris again, but it was still hidden -- so I lifted the whole scope up and moved it back one foot to the edge of the patio, and could find it easily.  A bright orange-red, brightest in field magnitude 6 (AAVSO agrees!).  The moon too bright, and the transparency now sheeting fog, to see much more of the field.