NASA’s Europa Clipper, pictured in this illustration, which was updated in December 2020, will orbit Jupiter on an elliptical trajectory, dipping close to its moon Europa on each flyby to collect data. Credit: NASA/JPL-Caltech
NASA‘c Europe The Clipper mission is focused on solving transistor radiation problems as it prepares to launch an expedition to Jupiter to study the habitability of Europa.
The mission faced challenges with radiation-resistant transistors, which were found to be less durable against Jupiter’s intense radiation. Tests at various NASA centers aim to address these issues.
Preparations for the launch of NASA’s Europa Clipper mission are progressing. The spacecraft was delivered to the Kennedy Space Center in Florida last May, and the team successfully installed the high-gain antenna.
Engineers on NASA’s Europa Clipper mission continue to conduct extensive tests on transistors that help control the flow of electricity in the spacecraft. The particular versions used by the Europa Clipper are radiation resistant and designed to withstand 100 to 300 kilorads, or krad (“rad” is a unit of measurement for an absorbed dose of ionizing radiation).
However, the mission team at NASA’s Jet Propulsion Laboratory (JPL) in Southern California, who managed the mission, evaluated test data that showed some transistors could be affected by significantly lower levels of radiation under some conditions. They are concerned that some of these parts may not withstand the radiation of the Jupiter system, which is the most radiation-intense environment in the Solar System.
Radiation challenges and ongoing analysis
Tests are also being conducted at the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland and NASA’s Goddard Space Flight Center in Greenbelt, Maryland. APL designed the spacecraft’s main body in collaboration with JPL and NASA Goddard.
The problem with the transistors came to light in May when the mission team was notified that similar parts were failing at lower radiation doses than expected. An industry alert was sent out in June 2024 to notify consumers of this issue. The manufacturer is working with the mission team to support ongoing radiation testing and analysis efforts to better understand the risk of using these parts on the Europa Clipper spacecraft.
Electronics durability and solutions
Test data obtained so far indicate that some transistors are likely to fail in the high-radiation environment near Jupiter and its moon Europa, because the parts are not as resistant to radiation as expected. The team is working to determine how susceptible the transistors can be and how they will perform in flight. NASA is evaluating options to maximize transistor longevity in the Jupiter system. The preliminary analysis is expected to be completed at the end of July.
Radiation-resistant electronics are used throughout industry to protect spacecraft from radiation damage that can occur in space. The Jupiter system is particularly harmful to spacecraft because its enormous magnetic field – 20,000 times stronger than Earth’s – traps charged particles and accelerates them to very high energies, creating intense radiation that bombards Europa and other interior moons. It appears that the problem that may be affecting the Europa Clipper transistors is a phenomenon that the industry was unaware of, and represents a newly discovered gap in the industry standard radiation qualification of batches of transistor wafers.
Mission objectives and future prospects
The Europa Clipper’s launch period begins on October 10, and it is due to arrive at Jupiter in 2030, where it will conduct research to understand Europa’s potential habitability as it flies by the moon multiple times.
The total cost of the Europa Clipper mission is estimated to be around $5 billion, making it one of the most expensive planetary science missions. This budget covers the development, launch and operation of the spacecraft for the planned duration of the mission.
