Juno takes the best close-up of icy moon Europa in decades


NASA has released a close-up of Jupiter’s ice-covered moon Europa, taken by NASA’s Juno spacecraft. during its flyby on September 29.

Revealing surface features in a region near the moon’s equator called Annwn Regio, the image was captured during the solar-powered spacecraft’s closest approach Thursday at 09:36 UTC, at a distance of approximately 352 kilometers.

This is only the third close pass in history below 500 kilometers in altitude and the closest look a spacecraft has given Europa since January 3, 2000, when NASA’s Galileo was 351 kilometers from the surface.

Europa is the sixth largest moon in the solar system, slightly smaller than Earth’s moon. Scientists believe that a salty ocean lies beneath a layer of ice miles thick, raising questions about possible conditions capable of supporting life below Europa’s surface.

This segment of the first image of Europa zooms in on a strip of Europa’s surface north of the equator. Due to the enhanced contrast between light and shadow seen along the terminator (the nightside boundary), rugged terrain features are easily seen, including tall blocks that cast shadows, while bright ridges and valleys and dark curve along the surface. The oblong hole near the terminator could be a degraded impact crater.

With these additional data on Europa’s geology, Juno’s observations will benefit future missions to the Jovian moon, including the agency’s Europa Clipper. Scheduled for launch in 2024, Europa Clipper will study the moon’s atmosphere, surface and interior, with the main scientific goal of determining whether there are places below Europa’s surface that could support life.

As exciting as Juno’s data will be, the spacecraft only had a two-hour window to collect it, passing the moon at a relative speed of about 23.6 kilometers per second.

“It’s very early, but everything indicates that Juno’s flyby of Europe was a great success,” he said. it’s a statement Scott Bolton, Juno principal investigator from the Southwest Research Institute in San Antonio. “This first image is just a glimpse of the remarkable new science that will emerge from Juno’s full suite of instruments and sensors that acquired data as we skimmed the moon’s icy crust.”

During the flyby, the mission collected what will be some of the highest resolution images of the moon (1 kilometer per pixel) and obtained valuable data on the structure of the Europa ice sheet, the interior, the composition of the surface and the ionosphere, in addition to the interaction of the moon with the magnetosphere of Jupiter.

“The science team will compare the full set of Juno images with images from previous missions, looking to see if Europa’s surface features have changed over the last two decades,” said Candy Hansen, a Juno co-investigator leading the camera planning at the Planetary Science Institute (PSI). “JunoCam images will complete the current geological map, replacing existing low-resolution coverage of the area.”

Close-up views of Juno and data from its Microwave Radiometer (MWR) instrument will provide new details about how Europa’s ice structure varies beneath its crust. Scientists can use all this information to generate new knowledge about the moon, including data on the search for regions where liquid water may exist in shallow underground pockets.

Building on observations from Juno and previous missions such as Voyager 2 and Galileo, NASA’s Europa Clipper mission, scheduled to arrive at Europa in 2030, will study the moon’s atmosphere, surface and interior, with the goal to investigate habitability and better understand its global subsurface. ocean, the thickness of its ice crust and look for possible plumes that may be expelling subsurface water into space.

The close flyby altered Juno’s trajectory, reducing the time it takes to orbit Jupiter from 43 days to 38 days. The flyby also marks the second encounter with a Galilean moon during Juno’s extended mission. The mission explored Ganymede in June 2021 and is scheduled to conduct close flybys of Io, the most volcanic body in the solar system, in 2023 and 2024.