Juno what, Europe? You look rugged • The Register

NASA’s Juno probe had a close encounter with Jupiter’s moon Europa on September 29, and this week the space agency released the highest-resolution photograph ever taken of its icy crust.

Europa has captured the imagination of scientists as there is a theoretical consensus that the moon’s frozen envelope harbors a vast salty ocean beneath it – an ocean that potentially contains twice as much water as Earth’s oceans combined. And this despite the fact that Jupiter’s moon is only 25 percent of the diameter of the earth.

The hope is that where there is water, life could arise – but Europe would need some other essential building blocks such as carbon, hydrogen, oxygen and sulfur to name a few.

It would also require energy to sustain life. Although Europa, Jupiter’s sixth satellite, is far from the Sun (about 485 million miles or 780 million kilometers), scientists believe that Jupiter’s strong gravity causes tides on Europa that expand and pull on the Moon, generating heat.

Though it looks like a desolate snowball on the surface, it could be one of the best candidates in the solar system to harbor extraterrestrial life, hence the close-up during Juno’s flyby.

Europa surface. Credit: NASA/JPL-Caltech/SwRI

Measuring approximately 93 miles (150 kilometers) by 125 miles (200 kilometers), the image brings into focus the network of ridges and troughs that criss-cross the Moon. NASA believes the dark spots at the top right and below center are evidence of surface eruptions, and the feature, which resembles a musical quarter note, measures 42 miles (67 kilometers) north-south and 23 miles (37 kilometers). ) in east-west direction.

“The white dots in the image are signatures of penetrating high-energy particles from the moon’s strong radiation environment,” NASA added.

The black-and-white photo was taken at a distance of 256 miles (412 kilometers) with Juno’s Stellar Reference Unit (SRU), a star camera used to point the spacecraft. Camera resolution ranges from 840 to 1,115 feet (256 to 340 meters) per pixel. The snap was taken as Juno hurtled past the nighttime region at 15 miles per second (24 kilometers per second), though “Jupiter shine” — sunlight reflecting off Jupiter’s clouds — cast a faint glow across the terrain.

In low light, the SRU excels. The hardware has spotted shallow illumination in Jupiter’s atmosphere since the probe’s arrival in polar orbit in 2016, giving a glimpse of the gas giant’s ring system.

“This image unlocks incredible detail in a region not previously imaged with such resolution and under such revealing lighting conditions,” said Heidi Becker, SRU’s lead co-investigator. “The science team’s use of a star tracker camera is a great example of Juno’s groundbreaking capabilities. These features are so fascinating. Understanding how they formed – and how they are connected to the history of Europe – informs us about internal and external processes that shape the ice crust.”

The image is further justification for NASA’s upcoming Europa Clipper mission, due to launch in October 2024. The spacecraft will take detailed measurements to study the moon’s habitability, although NASA notes: “Europa Clipper is not a life-detection mission — its main science goal is to determine if there are places beneath the surface of Europa that are home to life.” is possible.”

Meanwhile, the agency has welcomed its community of “citizen scientists” who have helped process raw images produced by JunoCam, the probe’s “public engagement camera,” during the September 29 flyby. NASA described this work as “not only impressive, but worthy of further scientific scrutiny.”

Image data: NASA/JPL-Caltech/SwRI/MSSS. Editing: Björn Jónsson

“Starting with our 2013 Earth flyby, Juno’s citizen scientists have been invaluable in processing the numerous images we receive with Juno,” said Scott Bolton, Juno principal investigator of the Southwest Research Center in San Antonio. “During each flyby of Jupiter and now its moons, their work offers a perspective that draws on both science and art. They are a crucial part of our team and lead the way by using our images for new discoveries. These latest images of Europa do just that, pointing us to surface features that reveal details about how Europa works and what might be lurking both on the ice and below.

NASA specifically highlighted the work of Navaneeth Krishnan, who increased color contrast to reveal surface features more clearly.

Image data: NASA/JPL-Caltech/SwRI/MSSS Image processing: Navaneeth Krishnan S © CC BY

While the scientific value of such processing should be obvious, some efforts have been a little, shall we say, psychedelic.

Launched in 2011, Juno took five years to reach the solar system’s largest planet, itself like a miniature solar system with its 80 moons. The probe continues to make discoveries about Jupiter and its satellites in its expanded mission, which will last until September 2025, or whenever the spacecraft stops functioning. ®