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 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 |
| Jul 20 | 05:28 | Io | Begin Shadow Transit |
| Jul 20 | 05:54 | Io | Begin Transit |
| Jul 20 | 07:42 | Io | End Shadow Transit |
| Jul 20 | 08:08 | Io | End Transit |
| Jul 21 | 02:35 | Io | Begin Eclipse |
| Jul 21 | 05:17 | Io | End Occultation |
| Jul 21 | 15:08 | Europa | Begin Shadow Transit |
| Jul 21 | 16:02 | Europa | Begin Transit |
| Jul 21 | 17:51 | Europa | End Shadow Transit |
| Jul 21 | 18:46 | Europa | End Transit |
| Jul 21 | 23:56 | Io | Begin Shadow Transit |
| Jul 22 | 00:24 | Io | Begin Transit |
| Jul 22 | 02:11 | Io | End Shadow Transit |
| Jul 22 | 02:38 | Io | End Transit |
| Jul 22 | 17:25 | Ganimede | Begin Eclipse |
| Jul 22 | 21:04 | Io | Begin Eclipse |
| Jul 22 | 22:21 | Ganimede | End Occultation |
| Jul 22 | 23:48 | Io | End Occultation |
| Jul 23 | 10:16 | Europa | Begin Eclipse |
| Jul 23 | 13:55 | Europa | End Occultation |
| Jul 23 | 18:25 | Io | Begin Shadow Transit |
| Jul 23 | 18:54 | Io | Begin Transit |
| Jul 23 | 20:39 | Io | End Shadow Transit |
| Jul 23 | 21:09 | Io | End Transit |
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.
