Deep Timken Expertise Enables Deep Space Exploration

The future of space flight is evolving at an astonishing speed. Unprecedented collaboration between public and private researchers is driving a new generation of technology for missions to further explore our moon, Mars and beyond.

Timken leverages its deep aerospace expertise and capabilities to help customers develop solutions where they didn’t exist before, for missions that are no longer impossible. John Renaud, principal application engineer, explains.

“We overdesign and overbuild our bearings to survive launch loads. Factors like required bearing life, contact stresses and system stiffness for later in the mission come along for the ride.”

John Renaud
Principal Application Engineer

Destination Europa

The largest spacecraft ever built for a NASA planetary mission, Europa Clipper launched in October 2024 and is currently getting a gravity assist from Mars to slingshot it faster and farther into deep space. Upon reaching Jupiter’s icy moon Europa in 2030, the spacecraft will gather images and data scientists can use to explore its geologic activity and ability to host life.

Timken collaborated with customer Johns Hopkins Applied Physics Lab (APL) to develop the pointing system for the narrow-angle camera (NAC) imaging system that will capture zoomed-in details of Europa’s surface.

The camera sits on a two-axis gimbal system that allows for precise positioning — a crucial element for gathering high-resolution images, groundbreaking measurements and detailed mapping of Europa. At the heart of the gimbal system are Timken® thin section ball bearings, which allow scientists to tilt the camera smoothly and accurately.

“Space flight is very specialized,” said John Renaud, a Timken principal application engineer with nearly 20 years of experience designing engineered bearings for space, commercial and military aviation. “Every new mission pushes boundaries to the extreme.”

Europa Clipper is no exception. The spacecraft and its NAC, which is relatively exposed given its position on the vehicle, is already subject to extremely low temperatures and high levels of radiation in flight. Once it arrives near Europa and begins operating in Jupiter’s shadow, system temperatures are expected to drop to a frigid -400˚F (-140˚C).

Yet according to Renaud, the greatest engineering obstacle is what happens on the launch pad.

“A spacecraft and its payload have to get off the planet first,” he said. “We overdesign and overbuild our bearings to survive launch loads. Factors like required bearing life, contact stresses and system stiffness for later in the mission come along for the ride.”

Engineers in a clean room at NASA’s Jet Propulsion Laboratory in Southern California build the nadir deck for NASA’s Europa Clipper spacecraft. Credit: NASA/JPL-Caltech

Sophisticated Modeling Advances Customer Innovation

Renaud and his team assisted APL engineers throughout their years-long development, modeling bearings against several camera design iterations.

During development, NASA modified Europa Clipper’s launch vehicle from the new Space Launch System (SLS) to the more cost-effective and readily available SpaceX Falcon Heavy rocket. This change would subject the NAC and its bearings to a different set of launch load conditions from what the spacecraft was originally designed to withstand. The change also extended the duration of Europa Clipper’s trip to Jupiter, dramatically increasing the bearings’ total exposure to cold and radiation.

Before and after the switch, engineers leveraged Timken® Syber® Bearing System Analysis, a robust bearing engineering platform, to model different geometries and materials to predict bearing life and performance. Modeling can be especially challenging for thin section bearings that have a high volume of rolling elements.

“The data helped us select materials atypical for these bearings, but crucial for the application,” said Renaud. “We developed a thin section ball-bearing using a steel retainer and applied a dry-film lubricant suited to both surviving launch loads and withstanding sustained extreme temperatures and radiation.”

Renaud added that customer collaboration was crucial. The Timken team provided APL engineers with bearings to build and test the camera prototype, as well as input for test conditions. After testing, APL provided critical load and performance data back to Timken to further refine bearing material selection.

“Everything survived launch in October,” Renaud added. “Once it approaches Europa, success will be based on the assumptions we made and the modeling we did together.”

Timken’s facility in Keene, NH specializes in super precision ball bearings as small as 1/8th inch in outside diameter. Because of the tighter precision tolerances, the bearings are assembled and inspected in “class 10,000 clean rooms,” which are nearly free of contamination.

A Legacy of Aerospace R&D, Focused on the Future

Throughout its journey, Europa Clipper will benefit from additional Timken bearing solutions in another crucial system — its reaction wheel assemblies (RWA). The RWA system stabilizes the Europa Clipper’s orbiter in flight to help maintain course and ensure accurate positioning of the NAC and other instrumentation, including antennae needed to relay data back to scientists on Earth.

It will also pass a series of other marvels made possible through more than a century of Timken aerospace innovation, like the most powerful telescope ever constructed and the rovers that have explored Mars for nearly 30 years.

Those innovations set the foundation for the next generation of aerospace technology, which is rapidly changing with space agencies’ ambitious new missions and the commercialization of activities like space travel and satellite communication.

“The fundamentals will stay the same,” Renaud concluded, “but we’ll continue to help customers push the envelope.”

Timken engineers help aerospace customers push boundaries and adopt new technologies. Learn how we are preparing for electric flight and enhancing the efficiency of traditional commercial flight with hybrid ceramic bearings.

Last Updated: 2025/03/7

Published: 2025/02/28