In Evidence
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Select a Solar System object and a date & time and view its location on our interactive planetarium.
Jupiter's Galilean Moons
Using this application it is possible to compute and visualize the positions of Io, Europa, Ganymede, Callisto - also known as the Galilean Satellites of Jupiter - in real time or at any given time in the past and in the future.
Upcoming Galilean Moons Phenomena
The following table lists all the upcoming events involving Jupiter's Galilean moons in the next 7 days.
| Date | Local Time | Satellite | Event |
|---|---|---|---|
| Jul 12 | 18:23 | Europa | Begin Eclipse |
| Jul 12 | 21:42 | Europa | End Occultation |
| Jul 13 | 03:34 | Io | Begin Shadow Transit |
| Jul 13 | 03:53 | Io | Begin Transit |
| Jul 13 | 05:48 | Io | End Shadow Transit |
| Jul 13 | 06:07 | Io | End Transit |
| Jul 14 | 00:41 | Io | Begin Eclipse |
| Jul 14 | 03:16 | Io | End Occultation |
| Jul 14 | 12:32 | Europa | Begin Shadow Transit |
| Jul 14 | 13:13 | Europa | Begin Transit |
| Jul 14 | 15:14 | Europa | End Shadow Transit |
| Jul 14 | 15:55 | Europa | End Transit |
| Jul 14 | 22:02 | Io | Begin Shadow Transit |
| Jul 14 | 22:23 | Io | Begin Transit |
| Jul 15 | 00:17 | Io | End Shadow Transit |
| Jul 15 | 00:37 | Io | End Transit |
| Jul 15 | 13:26 | Ganimede | Begin Eclipse |
| Jul 15 | 17:52 | Ganimede | End Occultation |
| Jul 15 | 19:10 | Io | Begin Eclipse |
| Jul 15 | 21:46 | Io | End Occultation |
| Jul 16 | 07:41 | Europa | Begin Eclipse |
| Jul 16 | 11:06 | Europa | End Occultation |
| Jul 16 | 16:31 | Io | Begin Shadow Transit |
| Jul 16 | 16:53 | Io | Begin Transit |
| Jul 16 | 18:45 | Io | End Shadow Transit |
| Jul 16 | 19:08 | Io | End Transit |
| Jul 17 | 13:38 | Io | Begin Eclipse |
| Jul 17 | 16:17 | Io | End Occultation |
| Jul 18 | 01:50 | Europa | Begin Shadow Transit |
| Jul 18 | 02:38 | Europa | Begin Transit |
| Jul 18 | 04:32 | Europa | End Shadow Transit |
| Jul 18 | 05:21 | Europa | End Transit |
| Jul 18 | 10:59 | Io | Begin Shadow Transit |
| Jul 18 | 11:23 | Io | Begin Transit |
| Jul 18 | 13:14 | Io | End Shadow Transit |
| Jul 18 | 13:38 | Io | End Transit |
| Jul 18 | 13:55 | Callisto | Begin Occultation |
| Jul 18 | 14:30 | Callisto | End Occultation |
| Jul 19 | 03:32 | Ganimede | Begin Shadow Transit |
| Jul 19 | 05:10 | Ganimede | Begin Transit |
| Jul 19 | 06:30 | Ganimede | End Shadow Transit |
| Jul 19 | 08:07 | Io | Begin Eclipse |
| Jul 19 | 08:12 | Ganimede | End Transit |
| Jul 19 | 10:47 | Io | End Occultation |
| Jul 19 | 20:58 | Europa | Begin Eclipse |
| Jul 20 | 00:31 | Europa | End Occultation |
Events are defined as follows:
- Occultation: the satellite is moving behind Jupiter from our perspective, so the satellite hides when the occultation begins and reappears when the occultation ends.
- Eclipse: the satellite is moving inside Jupiter's shadow. Sunlight is blocked by Jupiter and the satellite, no longer directly illuminated, is seen to disappear when the eclipse starts and reappear then the eclipse ends.
- Transit: the satellite is moving in front of Jupiter's disk. Depending on the conditions, the satellite can sometimes be difficult to see during a transit, appearing as slightly lighter or darker than Jupiter's clouds.
- Shadow Transit: the shadow of the satellite is moving on Jupiter's disk. The shadow typically appears as a dark circular spot clearly visible on Jupiter's clouds. This event, as seen from jupiter, is analogous to a solar eclipse.
Credits
The algorithms to compute the positions of the Galilean Moons used in this application are based on the jsaa project (Javascript Implementation of Astronomical Algorithms) which, in turn, is based on algorithms published by Jean Meeus on his Astronomical Algorithms book.
