I have never seen a Jovian moon while in eclipse, using apertures up to about 16 inches. I can't recall noticing a brightening or dimming rate tied to distance from Jupiter (and thus orbital speed). Sounds like you've got some homework to do. Now that you mention it, I'll probably remember to pay closer attention in the future. Jupiter will be paired closely with Venus in a few days/weeks, if my memory serves. On Jan 19, 2008 5:09 PM, Canopus56 <canopus56@yahoo.com> wrote:

Hi, Kurt, here. I've switched over to my generic astronomy newsgroup id.

...

From the 2008 RASC handbook, I am working up an ephemeris list of opportunities to view Jovain Moons as they exit or enter eclipse shadows. What I expect to see in small refractors or binos is a Jovian moon to simply disappear or appear while it is some distance from Jupiter.

I am doing this as my own personal observing project for 2008, but also was thinking that such a list might be useful for local scout clubs and astronomy parties, since it is the type of observation that a young boy or girl easily could do with binoculars from an urban setting.

Do the Jovian moons wink in or out of visibilty as the enter or leave Jupiter's eclipse pattern? Or are the Jovian moons faintly visible while they are in Jupter's eclipse shadow? If so, beginning at what apeture?

- Kurt, SLASer

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