The Dutch Observatory

Saturday morning was nice and crisp and wide thin and high cloud bands, but very humid which kept me busy between runs to keep my corrector plate from dewing up.  I managed one OK image during the 1 1/2 session.  Some indications of clouds can be seen over Olympus Mons and Tharsis or Arsia Silva.

Tonight was another opportunity for a mutual event with the moons Ganymede and Io.  Ganymede would occult Io starting at 22:20 UT and complete the occultation at 22:46 UT.  Both moons were travelling in the same direction.  In addition, the images taken see a moon shadow beginning a transit of Jupiter around 22:59 UT   and another shadow leaving the disk at approx. 22:55.  The problem was that local sunset was at 22:32 UT.  So I would need to start imaging before the sun had set.  I used my binoculars to locate Jupiter, but it took me until a few minutes into the event to get things positioned right.  In addition, I had a problem with WinJupos showing the graphical info for this specific date, so I checked Sky and Telescope, but they showed Ganymede’s shadow start crossing the disk at 23:02  and Io’s shadow leaving the disk at 23:06.  So I am confused.  Sorry for the everexposure of Jupiter, and not being able to calibrate this better because of the light conditions when I started.  Here the result of this ”early” event.