NASA just took another big step in its planned mission to Jupiter’s fascinating moon Europa. The mission is called Europa Clipper. Why clipper? Because Europa is thought to be an ocean moon, with a liquid ocean – two times the volume of all Earth’s oceans combined – beneath its icy crust. Is there life in Europa’s ocean? Maybe. Europa Clipper is designed to search for it. NASA said this month that the Johns Hopkins Applied Physics Laboratory in Maryland has now delivered the main body of Europa Clipper to the Jet Propulsion Laboratory (JPL) in Pasadena, California. Over the next two years, the rest of the spacecraft will be assembled at JPL, prior to launch in October 2024 and arrival at Jupiter in 2030.
Europa Clipper: Small but mighty
The main body of the spacecraft isn’t huge as spacecraft go, at 10 feet (3 meters) tall and five feet (1.5) wide. But later, when its solar arrays unfold, the overall spacecraft will be the size of a basketball court. Indeed, it is now the largest spacecraft NASA has ever developed for a planetary mission.
Likewise, this main body houses a powerful and complex robotic spacecraft, designed to study Europa in great detail. The body consists of aluminum stuffed with electronics, radios, thermal loop tubing, cabling and the propulsion system.
The main body consists of two stacked aluminum cylinders dotted with threaded holes. Engineers use those holes to bolt the body with the spacecraft’s cargo. This includes the radio frequency module, radiation monitors, propulsion electronics, power converters and wiring. Europa Clipper has eight antennas, including a high-gain antenna measuring 10 feet (3 meters) wide. The harness – the large collection of electrical wires – is also a big part of the spacecraft. The harness weighs 150 pounds (68 kilograms). If you stretched it out, it would run almost 2,100 feet (640 meters); that’s twice the perimeter of a football field.
The electronics are heavy-duty, designed to survive the intense radiation around Jupiter.
The body also contains two tanks, one for fuel and one for oxidizer. They help provide thrust for the spacecraft’s 24 engines. Tim Larson, deputy project manager at JPL, said:
Our engines are dual purpose. We use them for big maneuvers, including when we approach Jupiter and need a large burn to be captured in Jupiter’s orbit. But they’re also designed for smaller maneuvers to manage the attitude of the spacecraft and to fine-tune the precision flybys of Europa and other solar system bodies along the way.
An exciting time for Europa Clipper
Jordan Evans, Europa Clipper project manager at JPL, stated:
It’s an exciting time for the whole project team and a huge milestone. This delivery brings us one step closer to launch and the Europa Clipper science investigation.
APL designed Europa Clipper’s main body, along with JPL and NASA’s Goddard Space Flight Center. According to Tom Magner, assistant project manager:
The flight system designed, built, and tested by APL — using a team of hundreds of engineers and technicians — was the physically largest system ever built by APL.
What arrived at JPL essentially represents an assembly phase unto itself. Under APL’s leadership, this delivery includes work by that institution and two NASA centers. Now the team will take the system to an even higher level of integration.
9 science instruments
Europa Clipper has no less than nine science instruments onboard. They are also now arriving at JPL, where engineers will integrate them into the spacecraft itself. The first of these, the ultraviolet spectrograph (Europa-UVS), arrived at JPL in March. Next came the thermal emission imaging instrument (E-THEMIS).
Europa-UVS looks at Europa’s surface in the ultraviolet wavelength. That data tells scientists what kinds of materials are on Europa’s surface. The instrument primarily identifies relatively simple molecules, such as hydrogen (H2), oxygen (O2), hydroxide (OH) and carbon dioxide (CO2). It might also detect simple hydrocarbons such as methane (CH4) and ethane (C2H6). Those are building blocks for complex molecules like amino acids, which are the building blocks of proteins and the raw materials of life as we know it.
Europa-UVS will also study Europa’s very thin atmosphere and aurora, and search for the much-sought-after water vapor plumes.
E-THEMIS maps Europa’s temperatures in infrared and studies the moon’s geology. It will also look for some of the subsurface lakes – between the outer ice crust and the ocean below – that may exist. A study last April found that the odd ridges on Europa’s surface may form above those lakes.
A new view of Europa
The Europa Clipper mission is an exciting one, exploring this ocean moon up-close for the first time since the Galileo mission that orbited Jupiter from 1995-2003. It will conduct nearly 50 close flybys of the moon during its mission. Europa Clipper promises to revolutionize our understanding of this fascinating world and find out whether it could indeed be a home for alien life.
Bottom line: NASA’s Europa Clipper mission just completed another big step toward launch, the delivery of the spacecraft’s main body to JPL. Europa Clipper is scheduled to launch in October 2024 and will study Jupiter’s ocean moon Europa for evidence of habitability.
Read more about the Europa Clipper mission