Jupiter is about to become the great protagonist of the summer sky. The giant will in fact be in opposition on the evening of 10 June and will be visible throughout the night and in the best possible conditions.
What does it mean for a planet to be in opposition? The terms opposition and conjunction, referring to the outer planets, therefore from Mars onwards, are related to the Sun. When a planet is in conjunction, it means that it is covered by the Sun and therefore it is undetectable by the Earth, whereas when a planet is in opposition , means that the Earth is between the Sun and the planet and it is in the best possible observability conditions.
Jupiter will be at the minimum distance from the Earth, equal to about 641 million km, and will have the maximum apparent magnitude and the maximum angular diameter. These conditions will continue throughout the month of June and will be an excellent time to observe the gas giant. You can find it in the constellation of Ofiuco, it will rise in the east shortly after sunset and culminate in the south around midnight.
Even through binoculars, the four Galilean satellites will be visible: Europa, Io, Ganimede and Callisto. Europe is under the magnifying lens of astrobiologists as this moon would host, under the icy surface, an ocean of liquid water that could harbor primitive biological processes or elementary life forms. In fact, dedicated missions to this moon are being studied by NASA and ESA.
The oppositions of Jupiter take place on average every 13 months. The next will be in June 2020.