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Reminder of the first of 3 JEE events for North America Wednesday morning July 25th UT.

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Joined: 2012-07-03

Reminder for upcoming JEE2012 triple JEE observation July 25th 1h to 13h UT.

One of only three Jovian Extinction Events visible in North America occurs Wednesday morning July 25th UT. This is an interesting triple event where Europa's atmosphere passes in front Io twice in a game of cat and mouse where Io gets ahead of Europa once and then Europa overtakes Io a second time, followed shortly after that Io traverses through the western tip of it Torus and experiences dimming via self-extinction by its own dust and gas bound in the torus. This JEE will produce 3 minima in about 12 hours time. The first minima will occur before Jupiter rises over North America, but the East Coast can record the waning of the first minima and entire second minima. Viewers like me on the western part of the US will get the waning of the second minima and the onset of self extinction as Io enters the western Torus tip.

Combining East and West coast observations will create a nice long lightcurve for continued modeling of the atmosphere of Europa and the dust and gas particles in the Torus of Io. Observers in 6 countries have now chimed in on participating in JEE2012. The first observations have already been submitted for the first JEE2012 event of July 21UT by an AAVSO member. You too can participate by observing Io and Europa on the morning of July 25th with whatever photographic means capable. Instructions and predictions are posted here, and any questions and data acquired can be addressed to me, Scott Degenhardt

- complete prediction kit through Aug 2012:
-  Summary table of events through Aug 2012:

Clear skies!


FYI, August 4th and August 11th UT are about the only other JEE events visible in North America for 2012. This excludes Io Torus tip extinction events which actually occur once a day. I have not posted predictions for those yet unit we have arrived at a conclusive model to generate predictions with. I will announce those daily predictions within the next month or so. I have begun the prediction process through the end of 2013. After August 2012 the next events will occur starting January 2013 sporadically, and then in July 2013 they really pick up as the orbital plane of Jupiter is heading towards edge on. Jovian Mutual Events start up in September of 2014.

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