Why Only In M13?

[Bart]

Maybe this helps Bart

Thanks Tim

I can see it now in the photo, just surprised that's visible visually, if you know what I mean. Must try that out next time.

Thanks

[Tim]

Use the full size pic to get an orientation, you'll likely find it

[Mike73]

REALLY gonna try and spot this propellor, thanks for the image Tim.

[Scorpius]

Greetings Fellow Stargazers! I am resurecting this thread because I recently captured this photo of M13 which - at least to me - clearly shows a dark propeller-type feature does exist within that star cluster. One of the "blades" is more obvious than the other two and one is not readily visable at this exposure due to the lack of stars to provide some "backlighting" Anyway - this image was created from a stack of only twelve (40 Sec) lumnance subs which seems to indicate it may show up better in shorter exposures. I don't see how it can be said this is simply an illusion since the one obvious "blade" shows stars behind it which are dimmer than the adjacent ones not lying behind the area in questiion.

Thanks for looking and comments/opinions are always welcomed...  

[Stu]

The area you have highlighted is not part of the propeller most often seen. You have captured it though, it's down in the lower right quadrant of the GC and shows very clearly.

I saw this very clearly visually in my 16" at SGLX earlier this year.

Badly highlighted here!

[scarp15]

Scroll down this, achievable so I believe as a visual target to sketch, than to capture as a photographic image.

June's Challenge - M13 and the Illusive "Propeller"

[PeterW]

Caught it at a Starparty in a refractor. Give you something to look for.

Cheers

PeterW