Radar boom intended for future Jupiter mission tested, analyzed
HEILIGENBERG, Germany. The European Space Agency (ESA) recently tested a long radar boom that will probe below the surface of several of Jupiter’s moons during the future JUpiter Icy moons Explorer (JUICE) mission, which is scheduled for launch in 2022, arriving near Jupiter seven years later.
The JUICE mission will study Jupiter’s turbulent atmosphere and huge magnetic fields and will examine conditions on the planet-sized moons Ganymede, Europa, and Callisto. All three moons are thought to have oceans of liquid water beneath their icy crusts, according to ESA scientists, and may provide key clues on the potential for such bodies to harbor habitable environments.
ESA recently conducted a test of what it calls the Radar for Icy Moons Exploration using a helicopter -- operating out of a glider airport in Heiligenberg, Germany -- during which a 16-m (52.5-foot) long antenna was mounted on a simplified mockup of the eventual spacecraft and hung 150 m (492 feet) below the helicopter, which hovered between 50 and 320 m (164 feet and 1,050 feet) above the ground. The tests were done with the antenna and solar array in horizontal and vertical orientations to the spacecraft mockup, in an effort to gain a better understanding of the interaction between the spacecraft components and the antenna, and also to test the characteristics of the returned signals.
During the JUICE mission, once the antenna arrives at Jupiter's moons, it will transmit radio waves towards the surface and analyze the timing and strength of their reflections from features buried down to about 9 km (about 5.6 miles) . It will see vertical details as small as 50 m (164 feet). Data retrieved from these transmissions will help characterize the wide range of compositional, thermal, and structural variations that ESA scientists expect to find in the subsurfaces of these faraway planetary satellites.
Olivier Witasse, ESA’s JUICE project scientist, says of the radar element: “The radar is one of 10 instruments on our spacecraft that together will be the most powerful remote sensing, geophysical, and in situ payload complement ever flown to the outer solar system.”
The Radar for Icy Moons Exploration instrument consists of two main parts: The electronics are set to be provided by an international consortium from Italy and the US. Thales Alenia Space Italy is contracted to provide the electronics and integrate the instrument, while NASA's Jet Propulsion Laboratory (JPL) and the University of Iowa will provide the transmitter, receiver, and matching network hardware. The antenna is under procurement by Airbus, which is the prime contractor for the JUICE spacecraft prime contractor, and will be further developed with Germany's SpaceTech GmbH. The instrument is under construction through cooperation with Italy’s ASI space agency, which is also the lead funding agency, and NASA. The radar is a further development upon the instruments currently carried by ESA’s Mars Express and NASA’s Mars Reconnaissance Orbiter.