The mutual phenomena of the Galilean satellites of Jupiter

A Special IYA2009 project

We propose here to participate to the observation of the mutual phenomena of the Galilean satellites of Jupiter, joining the international network of observers. This network started working more than 20 years ago gathering scientific data of high interest allowing to know more about the Galilean satellites of Jupiter: Io and its volcanoes, Europa and its ice crust, Ganymede and Callisto. These observations are very rare since they are possible only at the time of the equinox on Jupiter, i.e. only every six years. The next opportunity will take place in 2009. Don't miss this opportunity the more so as these observations are possible even with a small telescope.
At the end of the campaign, all the observers will be associated to a scientific publication of all the observations made, published in an international journal (see the former publications ).

At the same time, similar events will occur among the satellites of Saturn: they will be much more difficult to observe, needing a more powerful telescope (with an aperture larger than 45 cm). Only experienced astronomers will be able to make these observations.

Here is a page dedicated to the observers who never made such observations.

In order to participate to this campaign of observations, please register through the registration page available here.

You will find hereafter a link to the official page of the network PHEMU09 dedicated to this campaign of observations.

a page of links to the observations made during the Phemu09 campaign;
a map of the observing sites of the Phemu09 campaign.

If you wish to continue observing and participating to scientific observational programs after 2009, we propose:

Last update: February 5, 2009

Contact: phemu09 (at)