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Upcoming satellite events on Jupiter

A fascinating series of double and triple phenomena of Jupiter’s moons will be occurring throughout October. The coupled orbits of the inner three moons mean that their phenomena recur at intervals of one week plus a few hours. The events this month are as follows. (In each case the shadows transit first, then the moons.)

Transits of I + III (with II entering eclipse in the meantime):
Oct.3, 10, 17, 24, 31.

Transits of I + II:
Oct.1, 8, 15, 22, 29/30;
Oct.5, 12, 19, 26.

The best event is on Oct.12, with the shadow of IV in transit along with the shadows of I + III. There will be at least 2 moons and/or shadows on the disk from 03:24-08:02 UT, so European observers should get a good view. Martin Mobberley has provided the diagram below of this triple-shadow event.

For those interested in making methane-band images of Jupiter, Christophe Pellier has posted the following useful article:

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