Mission Type: Flyby, Orbiter
NASA Center: Jet Propulsion Laboratory
Europa Multiple Flyby Mission Study Report
The Europa Multiple Flyby Mission concept would send a spacecraft to the Jupiter system to perform repeated close flybys of the giant planet's large moon Europa to investigate its potential habitability. The spacecraft would collect information on Europa's ice shell thickness, composition and surface geomorphology. The notional science payload consists of four instruments: a Shortwave Infrared Spectrometer (SWIRS), an Ice-Penetrating Radar (IPR), a stereo Topographical Imager (TI), and an Ion and Neutral Mass Spectrometer (INMS).
The nominal Europa mission would include 45 flybys of Europa at altitudes varying from 1675 miles to 16 miles (2700 km to 25 km). In the course of performing these flybys, the mission would also fly by the Jovian moons Ganymede and Callisto, although these flybys are solely to shape the orbit and would not drive science priorities.
The notional mission would launch from Cape Canaveral in the early 2020s and spend 6.5 years traveling to Jupiter. During this time, the spacecraft performs gravity assist flybys, first of Venus and then two of Earth, before swinging out to Jupiter. Upon arrival at Jupiter, the spacecraft would perform a nearly 2-hour main engine burn to allow capture into Jovian orbit. The spacecraft then performs four Ganymede flybys over the course of three months to reduce orbital energy and align its trajectory with Europa.
The mission would minimize the hazards posed by Jupiter's intense particle radiation environment in a manner similar to the Juno mission. The spacecraft would spend most of its time well outside the most intense regions of radiation, only diving in close to Europa for brief periods to collect precious science data during flyby encounters. The radiation hazard would be further minimized by placing the spacecraft's most sensitive electronics into a shielded vault. The vault would be placed in an area surrounded by propellant tanks for additional radiation shielding.
The Europa flyby campaign would be comprised of four segments each designed to provide good coverage of a wide region on Europa with consistent lighting conditions. During each flyby, a preset sequence of science observations would be executed. On approach the spacecraft would perform low-resolution global scans with its IR spectrometer ("nodding" the spacecraft's field of view back and forth across the moon, much like the Cassini spacecraft does during its moon flybys), followed by high-resolution scans with that instrument. At 1,000 km the ice-penetrating radar, topographic imager and ion and neutral mass spectrometer (INMS) would power up. The radar pass would occur from 250 miles (400-km) inbound altitude to 250 miles (400-km) outbound altitude, during which stereo imaging and INMS data are acquired continuously. During departure, the IR spectrometer would conduct additional high- and low-resolution scans as the spacecraft moves away from Europa.
Once the nominal mission (45 flybys) has been completed, the mission could continue to execute Europa flybys during an extended mission. The spacecraft would eventually be decommissioned via targeted impact on Ganymede before its propellant runs out or radiation damage compromises its electronics.