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Double Io and Europa Transit on Opposition Night Image 2016/03/07(UT)

Paul G. Abel

Paul G. Abel(203mm reflector)
Greetings all,
Please find attached my observation of the double Io Europa transit on opposition night (2016 March 7th). We had some very good seeing here at times and I used powers, of x200 x250 and x312 to get some excellent views.
I must confess I caught the event by accident- When I got out to the observatory I notices a d shadow on the disk (this was as it turned out, Europa's shadow) and just below it was a brilliant white spot which I initially took to be a similar one to the whit oval in the NEB at CM2~280. I decided that this couldn't be Io's shadow (which was nearby) so I went indoors to check WINJUPOS which informed me of the transit!
After examining the region where Europa was situated I found I could distinguish it fairly easily against the dark background of the NEB. Europa appeared to be a pearly white colour.
By 0026UT Io was on the following limb. Io's transit was more interesting: the satellite appeared as a brilliant spot against the NEB, and a definite orange hue was present. The shadow seemed to be more pronounced and at x250 it was quite clear that Io was 'eating' into its shadow- a thin black line on the left hand side of the satellite is all that could be seen.
Unfortunately the clouds then started to come in and in any case, seeing had broken down (although even in AIV Io could be made out but not Europa).
Finished observations by 0045UT. It really was quite a splendid

[Paul G. Abel:Leicester:United Kingdom]
ALPO-Japan Latest Oplanets Section
2016/04/06 [Venus Images before occultation]
2016/02/22 [GRS internal circulation on Feb 22]