Skip to main content

Juice spacecraft has overcome its stuck antenna issue and is ready for Jupiter

The European Space Agency’s Juice spacecraft is now fully deployed and on its way to study the icy moons of Jupiter. Launched in April, the Jupiter Icy Moons Explorer spacecraft has been through a complex and at times challenging deployment process over the past six weeks to unfold into its final form for its journey to Jupiter.

Large spacecraft like Juice need to be folded up during launch so that they can fit into the nosecone of their launch vehicle — in this case, an Ariane 5 rocket. Once the spacecraft has been deployed from the rocket, it can begin the process of unfolding while it travels through space.

An artist's impression of the Juice spacecraft fully deployed.
An artist’s impression of the Juice spacecraft fully deployed. ESA (acknowledgement: ATG Medialab)

The first parts to be deployed were the solar panels, which unfolded shortly after launch to their large size of 27 meters across. They provide power for the journey and the upcoming science mission. A communication antenna called the medium-gain antenna was deployed shortly after launch as well.

The challenge came from attempts to deploy a second antenna called the Radar for Icy Moons Exploration (RIME) antenna. At 16 meters long, this antenna is for a radar instrument that will be used to look beneath the surface of the icy moons. It was supposed to deploy five days after launch, but the antenna became stuck at the top of the spacecraft and couldn’t be released from its mounting bracket.

The Juice spacecraft has small, low-resolution monitoring cameras pointed at deployment points, so engineers were able to observe the antenna and see that the first section of the antenna had unfolded, but the other sections had not. The cameras did show some signs of movement, however, so there was hope. The images indicated that a stuck pin was holding the antenna sections in place, so the team fired Juice’s thrusters to shake the entire spacecraft. They also tried maneuvering the spacecraft into sunlight to help warm it up, in the hopes that would loosen the pin.

Neither of those approaches fixed the problem, so after several weeks, the team decided on a more drastic intervention, firing a device within the stuck bracket called a nonexplosive actuator. This component is designed to release a bracket by delivering a shock, which jiggled the stuck pin and let the bracket release. That finally allowed the last parts of the antenna to unfold and lock into place.

Other components like the magnetometer boom and more antennae were deployed without issue, and last week ESA announced that Juice is fully deployed as planned. With the spacecraft in configuration, now the team is ready to begin testing its instruments while the craft prepares for its first planetary flyby in 2024.

“It’s been an exhausting, but very exciting six weeks,” says Angela Dietz, deputy spacecraft operations manager for the mission, in a statement. “We have faced and overcome various challenges to get Juice into the right shape for getting the best science out of its trip to Jupiter.”

Editors' Recommendations

Georgina Torbet
Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…
See highlights of the launch of the European JUICE spacecraft
ESA’s latest interplanetary mission, Juice, lifted off on an Ariane 5 rocket from Europe’s Spaceport in French 09:14 local time/14:14CEST on 14 April 2023 to begin its eight-year journey to Jupiter, where it will study in detail the gas giant planet’s three large ocean-bearing moons: Ganymede, Callisto and Europa.

An Ariane 5 rocket carrying a spacecraft bound for Jupiter's icy moons was launched from Europe’s Spaceport in French Guiana at around 8 a.m. ET (5 a.m. PT) on Friday, April 14, in a spectacular daytime liftoff.

The Jupiter Icy Moons Explorer (JUICE) spacecraft from the European Space Agency has a mass of 2.6 tonnes and is carrying nearly 4 tonnes of fuel. This will be the final launch of an ESA mission using an Ariane 5 rocket, manufactured by ArianeGroup, as the rocket will now be succeeded by the upcoming Ariane 6 which is designed to be cheaper to launch.

Read more
How to watch JUICE mission launch to Jupiter’s icy moons
The European Space Agency's JUICE spacecraft.

[UPDATE: The original target launch date of Thursday, April 13, was called off due to poor weather conditions at the launch site. The JUICE mission is now targeting the morning of Friday, April 14. Full details below.]

Juice launch to Jupiter

Read more
Launch of Europe’s Jupiter Icy Moons Explorer delayed by 24 hours
An Ariane 5 rocket containing the Juice spacecraft on the launchpad at Europe’s Spaceport in Kourou, French Guiana, on Thursday April 13 2023.

The launch of the European Space Agency (ESA)'s JUICE mission to the icy moons of Jupiter has been delayed by 24 hours due to weather conditions. Risk of lightning near the launch pad at Europe’s Spaceport in Kourou, French Guiana meant that the launch was scrubbed around 10 minutes prior to the scheduled liftoff today, Thursday, April 13.

Juice launch to Jupiter

Read more