Jupiter’s particle radiation field is 20,000 times larger than Earth’s Van Allen belts, and 1,000 times more intense than Saturn’s. The collosal planet rotates once every 10 hours (a Jupiter day). Jupiter pulls its magnetic field right along with it. The magnetic field hauls charged particles around Jupiter at blistering speed. And Europa orbits Jupiter in the heart of that torrent of particles.
Europa Clipper’s radiation study aims to improve future spacecraft design. It will help scientists understand Jupiter’s particle radiation environment in general. But it will also study how particle radiation affects Europa’s surface and surroundings.How It Works
How It Works
Jupiter's magnetic field is the largest and most intense in the solar system, aside from the Sun. Its magnetotail sometimes reaches Saturn’s orbit. The magnetic field traps electrons and protons – charged particles. Europa Clipper’s radiation monitors will study those particles.
Europa Clipper will carry radiation sensors at more than a dozen locations on the spacecraft. The monitors will measure the total ionizing dose, which is the cumulative radiation the spacecraft encounters. Another sensor will measure electrons directly. “Electrons dominate the Europa environment,” said JPL radiation scientist and engineer Insoo Jun, co-chair for Europa Clipper’s radiation focus group. “There are some protons and other heavier ions, but the sensor will measure electron intensity,” he said.How We'll Use It
How We'll Use It
The radiation monitors will provide a clearer picture of Jupiter’s high-energy particles. “Their energies are relativistically high,” Jun said. “We want to know how those particles are distributed, how the Jovian magnetosphere behaves, and how it accelerates the particles.”
The radiation team will also analyze the radiation’s effect on Europa’s surface chemistry. “Maybe it affects the moon’s habitability,” Jun said. Another Jovian moon, Io, erupts nonstop, and some of its material gets ionized and carried off by Jupiter’s magnetic field. “It can affect the neutral and ionospheric environment around Europa,” Jun said.
The radiation study will also improve computer models of Europa’s radiation. Those models will help engineers design future spacecraft, such as a possible Europa lander mission.
Meet the Team“We can only have so many Europa missions in my lifetime, so this may be a once-in-a-lifetime mission.”
Meet the Team
“The radiation monitors are our primary source of data,” Jun said. “But we will also collect data from many of the science instruments such as MASPEX, UVS, MISE, and EIS.” What other instruments see as “noise” can be useful data for the radiation study, Jun said.
Data on the outer planets is scarce because few spacecraft have made the long trip. “We can only have so many Europa missions in my lifetime, so this may be a once-in-a-lifetime mission.”