The Dutch Observatory

Tonight Jupiter’s moons would be subject to another mutual event and my intentions were to try to capture some “bigger” moons this time.  The moon Io would be occulted by Europa with a total relative intensity drop of 40%.  Altough it was clear, the weather was pretty bad for observing and imaging with the image blowing all over the chip.  I did not realize that Io was not visible to start with, because it was in Jupiter’s shadow.  So I was questioning myself if the event would take place.  I started recording anyway, because I was setup .  To my big surprise, Io all of a sudden started shining a few minutes before the event and I did complete observing and recording the event despite the bad seeing.  After the fact, it would have been better to image this at f/15 rather than f/30 so the images would have been less blurry.  But I was happy to have observed and imaged my 4th mutual event this apparation!  Click the image to activate the animation!

The clear Skies continued, but the seeing was not good, with winds picking up, making Mars jump all over the chip.  Here the only presentable image from this morning. 

The sky was clear again, and I am taking every opportunity to image.  Here is Jupiter with Io transitting the CM just before Jupiter disappeared in the trees to the West. 

The nice weater continued and conditions to observe Jupiter were great!  I made 5 images of which this one is the first.  I also did some more testing with the sample ratio for my imaging.  Most images I make are made with the Williams Optics 2x barlow used in binos, which result in an f-ratio or f/15.  Using the Celestron 2x shorty plus with my extension tubes allows me to go up to f/30, but at a far increased exposure time and the result is not as nice.  This image shows the GRS just sliding off the side and Ganymede getting ready to disappear behind the planetary disk.

The forecast was clear for early this morning and the rest of the day, but clouds have moved in.  However, it left me an opportunity earlier this morning to capture Mars. (Now an hour earlier since we switched to daylight savings time yesterday).  Here Mars and Syrtis Major, with Hellas very bright above it and the polar cap visible below it.   Deucallonis Regio shows up bright also above the dark Sinus Sabeaus to the right of Syrtis Major.  I am not sure if the dark area below Syrtis Major is Boreo Syrtis.

The forecast showed better conditions for 5:00 A.M.  So I set my alarm clock for 4:30.  It was clear, but the humidity was 90% and it kept me going to keep the corrector plate from dewing over.  Once I setup,  I thought I had problems with my Celestron barlow lens, but when positioned in front of  the filter wheel, the magnification was too big and I did not get enough light to get decent exposures, so the the barlow went back behind the filter wheel again.  Here my Mars image from this morning.  The clouds moved in before I knew it and I could not even complete the blue AVI of the second set.  Here Mars with Syrtis Major at the CM on the evening limb.

After 9 days of clouds and rain, the sky broke open a little.  However, I could see the cloud cover to the west and south.  But it was OK for the time it took me to image Jupiter again.  Conditions were still very humid, with transparency around 4/10 and seeing 5/10.  Here one of the 5 images from Thursday evening with Io just starting its transit.

Today was a busy day with the chapter doing an outreach program for the Children School of Atlanta at Charlie Elliott Wildlife Center.  The seeing and transparancy were great but with a very high humidity, which required me to use my “hairblower” on the corrector plate several times to keep it from dewing over.  So I took the opportunity to finish the event making an image of Jupiter with the GRS.  Here Jupiter with the GRS and Europa.  Notice how the channel around the GRS has broken into the SEB.  I wonder how this will develop.

I’ve been imaging Mars earlier this week, but had problems processing them.  Here an image from this morning when the seeing was pretty good.  However I could hardly keep the dew off my corrector plate.  Here Mars as it becomes more active.

I did finish the animation sequence of 1 1/4 hour of rotation of the planet.  I had to stop imaging because Jupiter started to get behind the trees that obstruct my view of the Western sky.  So here the animation.  Visible is also Io as it approaches the planet and starts its transit.  (Click the thumbnail to start the sequence.)