Artist's impression of the JUICE mission to Jupiter
Even before the giddiness wears off from the successful New Horizons fly-by of Pluto space scientists are planning new explorations of the solar system. This week the European Space Agency (ESA) selected Airbus Defence & Space as its prime industrial contractor for the JUICE (JUpiter ICy moons Explorer) mission to Jupiter and its satellites: volcanic Io, icy Europa, rocky/icy Ganymede and Callisto. The contract covers the industrial activities for the design, development, integration, test, launch campaign and in-space commissioning of the spacecraft, which will be launched in 2022 from Europe’s spaceport in Kourou, French Guiana, on an Ariane 5 rocket, arriving at Jupiter in 2030 to spend at least three years making detailed observations.
With Europa, Ganymede and Callisto all believed to have internal oceans, the mission will study the moons as potential habitats for life in an ongoing attempt to determine the conditions needed for planet formation as well as looking for clues as to how life emerges and how the Solar System works. JUICE will make the first measurements of the thickness of Europa’s icy crust and try to identify candidate sites for future spacecraft landings. It will continuously observe Jupiter’s atmosphere and magnetosphere, and the interaction of the moons with the gas giant planet.
JUICE will be equipped with 10 instrument packages, including spectrometers, cameras, radar to penetrate ice, an altimeter and sensors to monitor magnetic fields and charged particles. The Jovian moons Callisto and Ganymede will assist JUICE as their gravity will be used to modify the spacecraft's trajectory to enable two Europa flybys to determine the composition of non-water-ice material on its frozen surface. Callisto’s gravity will be also employed to raise the orbital inclination of the spacecraft so as to observe Jupiter's polar regions.
A high gain antenna about 3m in diameter will provide at least 1.4 Gb of daily data downlink. Because of the distance to Earth back-and-forth signals from the spacecraft will take up to 1h 46 m, meaning the spacecraft must be capable of a certain amount of autonomous operation.
NASA also hopes to study the Jovian moon Europa, NASA’s fiscal year 2016 budget request includes $30 million to formulate a mission to Europa in the 2020s. The mission would send a solar-powered spacecraft into a looping orbit around the gas giant Jupiter to perform repeated close flybys of Europa over a three-year period at altitudes ranging from 25 km to 2,700 km. Earlier this year the space agency selected nine science instruments to investigate whether the mysterious icy moon could harbor conditions suitable for life. The payload of selected science instruments includes cameras and spectrometers to produce high-resolution images of Europa’s surface and determine its composition. Ice penetrating radar will determine the thickness of the moon’s icy shell and search for subsurface lakes similar to those beneath Antarctica. The mission also will carry a magnetometer to measure the strength and direction of the moon’s magnetic field, which will allow scientists to determine the depth and salinity of its ocean.