[Lvas] M13 propeller

[David Blanchette]

I have to admit, when I first heard about the "dark lanes" and 
"propeller" in M13, I was rather skeptical.  I pulled up a couple of 
images of M13 off the net, ran them through some contrast adjustments 
in a photo editor, but did not see what was described.

Then someone sent a pair of images of M13, one with an overlay of a 
propeller.  Thereafter, I couldn't help but see the propeller in many images.

Tuesday night, Rob and I were up at Camp Lee Canyon, for a school 
event.  Once it got real dark, and M13 peeked out from behind the 
trees, I slapped 200x of 12" LX200 SCT on it, and, sure enough, there 
was the propeller!

Wondering if I was just preconditioned to see it, I called over the 
teacher who was running the event.  I explained that there were dark 
lanes in M13, that formed a 3-blade propeller.  It was about the size 
of the central core of M13, and not centered.  I paused to see if I 
needed to give any other clues, but he almost immediately said 
"...it's down at the bottom?..."  He had nailed it, first try.

So it does seem to be real, but it doesn't seem to photograph well 
(gets washed out by stacking?)  I need to get out and try it 
sometime, maybe at Cathedral Gorge next weekend.

-- David