On Thursday, a NASA spacecraft passed by one of our most fascinating ocean worlds.
Juno, a spacecraft orbiting Jupiter since 2016, made the closest approach to Europa at 5:36 AM. ET flew within 219 miles (352 km) of its icy surface.
Juno captured some of the most high-resolution images of Europa’s ice shell. The first image has been sent to Earth. It shows surface features in Anne Regio, a region north of the moon’s Equator.
NASA released this statement: “Due to the enhanced contrast of light and shadow along
the terminator, the nightside boundary), rugged terrain characteristics are easily seen, including tall shadow casting blocks while bright and dark Ridges and Troughs curve across it,” “The terminator’s oblong pit may be an impact crater in decline.”
The spacecraft also collected data on the moon’s interior. It is believed that there may be a salty ocean.
Scott Bolton, Juno’s principal investigator at San Antonio’s Southwest Research Institute, stated that although it is still early in the process, Juno’s Europa flyby was a huge success.
“This is only a small glimpse of the amazing science that Juno’s whole suite of sensors and instruments will produce as we scan the moon’s icy crust.
The moon’s ice shell is 10 to 15 miles (16 to 24 kilometers thick) thick. Its ocean likely lies on top of an ocean that is 40 to 100 miles (64-161 kilometers) deep.
Juno’s Microwave Radiometer instrument, which is part of Juno’s Microwave Radiometer system, will examine the ice crust to learn more about its composition and temperature. This is the first time that this type of information has been collected about Europa’s frozen shell.
Juno’s data and images could be used to inform NASA’s Europa Clipper mission. It will launch in 2024 and perform 50 dedicated flybys around Earth after arriving in 2030. Europa Clipper could help scientists discover if there is an interior ocean and whether it might be habitable for human life.
Clipper will eventually drop to an altitude of just 16 miles (26 km) above the surface of the moon. Clipper will focus on Europa observation, while Juno has been primarily focused on Jupiter.
Bolton stated that Europa is an interesting Jovian moon and will be the focal point of its future NASA mission. “We are happy to provide data that could help the Europa Clipper mission planning team as well as new scientific insights into this world.
All instruments on Juno collected data during the flyby. These included those that could measure Europa’s atmosphere’s top layers and how Europa interacts with Jupiter’s magnetic field. The team hopes to see a water plume rise from cracks in the ice shell. In the past, missions have seen water vapor plumes erupting from the ice shell into space.
Bolton stated that although we have the equipment necessary to complete the task, it will take a lot of luck to capture the plume. “We must be in the right place at the right time. If we are lucky, it’s a home run for certain.”
Juno is currently in the extended portion of its mission. It was scheduled to finish in 2021. The spacecraft now focuses on flybys of Jupiter’s moons. The spacecraft visited Ganymede in 2021 and will zoom past Io in 2023-2024. The spacecraft’s mission will end in 2025.
The Europa maneuver reduced Juno’s orbit around Jupiter by 43 days to 38 days.
The spacecraft flew by the moon quickly at 52,920 miles an hour (85,167 km per hour).
Europa is approximately 90% the size of Earth’s Moon, and Juno’s orbit was the closest that a NASA spacecraft had come to it since 2000’s Galileo mission.
“The science team will compare the complete set of Juno images with images from other missions, looking for changes in Europa’s surface features,” Candy Hansen, Juno coinvestigator, said in a statement. She is also the lead planner for JunoCam at the Planetary Science Institute, Tucson, Arizona.