NASA has released the clearest images ever taken of the radiation belt of Earth’s magnetosphere. But the spacecraft that accomplished this feat was not only designed to detail the vital atmospheric region that protects the planet from harmful cosmic rays; it is also in the early stages of a multi-year journey to Jupiter.
The European Space Agency’s Jupiter Icy Moons Explorer (JUICE) probe, launched on April 14, 2023, has currently begun a journey to the solar system’s largest planet. Once JUICE finally arrives in July 2031, it will analyze Jupiter’s magnetosphere while simultaneously collecting information about three of its 79 moons: Callisto, Europa and Ganymede. Before it gets there, however, the spacecraft will have to harness the gravity of multiple planets to properly adjust its speed and trajectory. And according to NASA, engineers wanted to make the most of the first meeting.
The agency detailed both the new images and the first-ever moon-Earth flyby and dual gravity assist maneuver in history in a October 1 announcement. Starting on August 19, the first of two instruments, the Jovian Energetic Electrons (JoEE) instrument, powered up as JUICE passed about 750 kilometers above the moon’s surface. During this 30-minute period, JoEE collected data on how the space environment around the moon affects Earth’s only (permanent) natural satellite. The short experiment served as a successful trial period for what JoEE will hopefully achieve on a much larger scale once it approaches Jupiter.
But JUICE wasn’t done yet. On August 20, the spacecraft traveled through Earth’s magnetosphere, about 120,000 feet (37,000 meters) above the Pacific Ocean. During this phase, the built-in Jovian Energetic Neutrals and Ions (JENI) tool, built by the Johns Hopkins Applied Physics Laboratory (APL), underwent its own stress test. JENI used its highly sensitive camera sensors to capture the energized neutral atoms emitted by charged particles when they come into contact with Earth’s atmospheric hydrogen gas.
“I couldn’t have hoped for a better flyby. The wealth of data from our deep dive through the magnetosphere is astonishing,” said Pontus Brandt, APL principal investigator for JoEE and JENI. Tuesday’s announcement. “JENI’s view of the entire system we just flew through was the icing on the cake. It is a powerful combination that we will exploit in the Jovian system.”
[Related: Jupiter’s moons are about to get JUICE’d for signs of life.]
Surviving the million-degree plasma clouds that surround Earth is relatively easy for inanimate space probes. But the potential impacts of this region – also known as the Van Allen radiation belt – pose a serious challenge to any long-term human journeys to the moon and Mars. According to NASA, the information analyzed by JENI and JoEE will help better plan for these and other issues surrounding the future of space travel.
As for JUICE, it’s now hurtling toward Venus, where it will perform a similar gravitational catapult in August 2025. It will then return to Earth for additional passes in September 2026 and January 2029. After all that, it’s finally on to Jupiter.
