The Juno spacecraft is well-known for the stunning images of Jupiter captured by its JunoCam instrument, like the one featured above, captured on Juno's 38th pass on Nov. 29. However, Juno scientists recently published something unique: an audio track acquired by Juno while flying by Jupiter's moon Ganymede.
The brief audio piece was created using data acquired by Juno's Waves instrument and conveys the strange and amazing sounds of space travel. This instrument studies Jupiter's magnetosphere, or magnetic field, to better understand how it interacts with gases in the atmosphere. During its flyby of Ganymede, it collected data on electric and magnetic waves, which was later translated into the audio range.
This audio was unveiled at the American Geophysical Union Fall Meeting 2021.
"This soundtrack is just wild enough to make you feel as if you were riding along as Juno sails past Ganymede for the first time in more than two decades," physicist Scott Bolton of the Southwest Research Institute, Juno's principal investigator, said.
"If you listen closely, you can hear the abrupt change to higher frequencies around the midpoint of the recording, which represents entry into a different region in Ganymede's magnetosphere."
Transposing data into audio frequencies isn't just for fun; it's a new way of accessing and experiencing the data, which can help you see fine subtleties that might otherwise go unnoticed. With a variety of probes, including the Voyager spacecraft and planetary missions, we've been capturing the "sounds" of the Solar System.
Ganymede has a fully differentiated core and a liquid ocean beneath its frozen surface that may host life. It also possesses its own magnetic field, making it the only moon in the Solar System with one.
The Galileo probe also took samples of the space near Ganymede, revealing that plasma waves around the moon are a million times stronger than the median activity at similar distances around Jupiter. It's unclear whether this has anything to do with the moon's magnetic field, but it appears to be the case.
At a relative velocity of 67,000 kilometers per hour, Juno traveled as low as 1,038 kilometers (645 miles) from the moon's surface (41,600 mph). Scientists have a few ideas about what the new data will reveal, but it's still a work in progress.
Since the Galileo spacecraft's approach in 2000, Juno's flyby of Ganymede was the closest a spacecraft has ever come to the Solar System's largest moon, which is bigger than the planet Mercury.
