The launch was scheduled for Thursday, but was postponed to today at 13:14 (Lisbon time) due to adverse weather conditions, in case there of a risk of lightning.

The European rocket Ariane 5 that will carry the satellite will depart from ESA in Kourou, French Guiana, where Portugal, a member of ESA, will be represented by the president of the Portuguese space agency Portugal Space, Ricardo Conde.

The mission has aerospace engineer Bruno Sousa as director of flight operations and antennas engineer Luís Rolo tested two antennas of two of the satellite's ten instruments, a radar probe and a radio telescope. Both have worked at ESA for over ten years.

The 'Juice' satellite (acronym for JUpiter ICy moons Explorer, Explorer of the Icy Moons of Jupiter) includes components, such as thermal coatings, magnetic field and autonomous navigation systems and instruments, such as radiation monitors and solar panels, manufactured by the companies LusoSpace, Active Space Technologies, Deimos Engenharia, FHP - Frezite High Performance, Efacec and LIP - Laboratory of Instrumentation and Experimental Particle Physics.

The 'Juice' will study the largest planet in the Solar System and the moons Europa, Ganymede and Callisto, where scientists think that liquid water (a fundamental element for life as we know it) may exist under the ice crusts on the surface.

The ESA mission, which earned the Portuguese companies involved 5.4 million euros in contracts, was designed to find out whether there will be sites around Jupiter and inside the icy moons with the necessary conditions (water, energy, stability and biological elements ) to support life.

The satellite should reach the gas giant, taking advantage of the gravity of Earth and Venus at different times, after eight years, in July 2031, make 35 close flights to the icy moons (discovered by Galileo 400 years ago) and reach Ganymede in December from 2034.

It will be the first time that an artificial satellite will orbit a moon of a planet other than Earth.

The first scientific data are expected in 2032.