[ngcles]

Hi All,

At the risk of making this an endless battle of opinions (I wasn't going to add further posts to this thread), I'd offer just one other solid fact that bears closely upon whether it is truly possible to observe/detect/see the Encke Division itself as opposed to the minima.

That portion of the "A" ring that lies outside the Encke Division at best measures 0.5 arc-seconds in angular diameter -- somewhat less (about 25% less) than the angular width of the Cassini Division that separates the "A" and "B" rings.

If the angular resolution capability of the telescope employed is higher than 0.5 arc-seconds (for the record 7" is 0.64") the simple effects of diffraction will blend the division into the darkness at the outer edge of the "A" ring, resulting only in a diffuse dimming of the ring edge, rather than the visibility of a narrow division. It matters not how good the observer's eyes are, if the 'scope has insufficient aperture, the wave nature of light will prevent the detail from being viewed.

I'm sorry, but I remain firmly unconvinced that the Encke Division is actually observable/detectable/see-able in apertures less than 25cm (more likely 28-30cm): Even with a perfect (unobstructed) optic set (these don't exist), in perfect seeing and assuming the observer has high visual acuity. Don't blame me, blame physics.

As Foghorn Leghorn said to the the young chicken hawk: "Son, I say son (listen to me when I'm talkin' to yer), you can argue with me, but you can't argue with figures".

Best,

L.