NASA's Juno Captures Highest-Resolution Image Of Jupiter's Moon Europa, Reveals Its Fractured Icy Crust

Juno's image of Europa shows a region crisscrossed with a network of fine grooves and double ridges, which are pairs of long parallel lines indicating elevated features in the ice. 

NASA's Juno spacecraft, which made its closest approach to Jupiter on September 29, 2022, at a distance of 352 kilometres, has captured the highest-resolution photograph of the Julian moon Europa. Juno's image reveals a detailed view of Europa's heavily fractured icy crust. It shows a region crisscrossed with a network of fine grooves and double ridges, which are pairs of long parallel lines indicating elevated features in the ice. 

What Europa’s image reveals

Juno's image of Europa covers about 150 kilometres by 200 kilometres of Europa's surface. Dark stains which could be linked to something from below erupting onto the surface can be seen near the upper right of the image, and just to the right and below centre, NASA says on its website. 

Below the centre and to the right, a surface feature, appearing like a musical quarter note, is seen. The feature measures 67 kilometres north-south by 37 kilometres east-west. The white dots seen in the image represent signatures of penetrating high-energy particles from the severe radiation environment around the moon. 

Juno's Stellar Reference Unit (SRU) captured the black-and-white image during the spacecraft's flyby of Europa on September 29. The SRU is a star camera used to orient the spacecraft. As Juno raced past Europa at about 24 kilometres per second, over a part of the surface that was dimly lit by "Jupiter's shine" at nighttime, Juno's SRU captured the image with a resolution that ranges from 256 to 340 metres per pixel. Jupiter's shine refers to sunlight reflecting off Jupiter's cloud tops. 

The SRU is designed for low-light conditions, and has achieved milestones such as discovering shallow lighting in Jupiter's atmosphere, imaging Jupiter's enigmatic ring system, and recently providing a glimpse of some of Europa's most majestic geologic formations. 

Is life possible on Europa?

Europa is the solar system's sixth-largest moon with about 90 per cent the equatorial diameter of Earth's Moon, and is believed to have a salty ocean below a thick ice shell. NASA's Europa Clipper spacecraft will arrive at the moon in the early 2030s, and attempt to answer questions about Europa's habitability. 

Last year, NASA's Hubble Space Telescope discovered the presence of persistent water vapour in Europa. However, the evidence of water vapour was found only in one hemisphere.

Earlier this year, a study said that the ice shell of Europa may have an abundance of water pockets beneath similar features that are common on the surface. The results may be compelling for detecting potentially habitable environments within the exterior of the Jovian moon.