Juno’s close pass of Europa on September 29 (1036 UTC) took it within 352 kilometers of the icy moon, marking the third close pass in history below 500 kilometers. The encounter saw the spacecraft come within a single kilometer of Galileo’s 351 kilometers from the surface back in January of 2000, and it provided the opportunity for Juno to use its JunoCam to home in on a region north of Europa’s equator. Note the high relief of terrain along the terminator, with its ridges and troughs starkly evident.
Image: The complex, ice-covered surface of Jupiter’s moon Europa was captured by NASA’s Juno spacecraft during a flyby on Sept. 29, 2022. At closest approach, the spacecraft came within a distance of about 352 kilometers. Credit: NASA/JPL-Caltech/SWRI/MSSS.
This first image from JunoCam captures features at the region called Annwn Regio, and was collected in the two-hour window available to Juno as it moved past Europa at 23.6 kilometers per second. What we hope to gain from analysis of the data should be high resolution images at approximately 1 kilometer per pixel, along with data on the ice shell covering the moon’s ocean, along with a good deal more about its surface composition, its internal structure and tenuous ionosphere. Says Candy Hansen, a Juno co-investigator (Planetary Science Institute, Tucson):
“The science team will be comparing the full set of images obtained by Juno with images from previous missions, looking to see if Europa’s surface features have changed over the past two decades. The JunoCam images will fill in the current geologic map, replacing existing low-resolution coverage of the area.”
In other words, more JunoCam imagery to come, all useful to the upcoming Europa Clipper and JUICE missions. In particular, data from the spacecraft’s Microwave Radiometer should fill in our understanding of variations in Europa’s ice beneath the crust, and possibly point to regions where liquid water may be captured in subsurface pockets.
While Junocam is a welcome addition to the spacecraft, it’s image quality has been underwhelming. Aimed at the colossus of Jupiter, the pictures appear decent, but compared to Galileo’s images of Europa Junocam’s results are disappointing. Juno’s 1km/px vs Galileo’s 6m/px from over 500km altitude in 1997. Even Voyager managed 2km/px. Looking forward to 50m global mapping from Europa Clipper with much higher res at selected sites.
John Walker, keep in mind the Juno team didn’t even WANT a camera on their probe at first! Mindboggling idea, I don’t care what their needs or budgets were. Note how deep space missions which did and do not have cameras often get left out in the news and even history. Plus how can you not want to see what is going on out there?
https://en.wikipedia.org/wiki/JunoCam
So is Europa a lot grayer (blander) in color than previous close up images of the moon have shown? Are the reddish-brown cracks not so reddish-brown and what does that mean in terms of potential organics?
https://apod.nasa.gov/apod/ap221003.html
Remember when Io was first shown in 1979? It was compared to a pizza, all bright reds, oranges, and yellows. The colors were later toned down to more greens and yellows after calibrations.
Don Davis investigated the true colors of Jupiter’s Galilean moons here:
https://pirlwww.lpl.arizona.edu/HIIPS/EPO/index.html
https://pirlwww.lpl.arizona.edu/HIIPS/EPO/gallery.html
A detailed processed image of Europa – It sure looks amazing one of the best images Iv’e seen.
https://www.flickr.com/photos/kevinmgill/52393871243
The close up images of Europa, prompting anyone with vision and care to ask why we don’t already have a fleet of exploration missions at that moon…
https://www.universetoday.com/157961/here-are-the-high-resolution-images-of-europa-captured-by-juno-during-its-recent-flyby/
ljk, there is no such thing as true color, and so there’s no real answer as to whether Europa’s non-icy areas are bland or not. Look at the landscape in the photos that Apollo astronauts took on the Moon, then take a picture of the full Moon with your camera phone, and it’s very likely that they will “disagree” profoundly. Neither of those is wrong, and so it is with Europa, too. Photos are decor for us; accurate spectroscopy is another matter.