May 12, 2024

New Explanation Uncovered for the Mysterious Motion of Europa’s Icy Shell

This view of Jupiters icy moon Europa was captured by the JunoCam imager aboard NASAs Juno spacecraft during the missions close flyby on September 29, 2022. When it reaches orbit around Jupiter in 2030, the firms Europa Clipper spacecraft will explore the moon. Credit: Image data: NASA/JPL-Caltech/SwRI/ MSSS, Image processing: Kevin M. Gill CC BY 3.0
Research study reveals a brand-new description for how the icy shell of Jupiters moon Europa turns at a various rate than its interior. NASAs Europa Clipper will take a closer look.
NASA researchers have strong proof that Jupiters moon Europa has an internal ocean under its icy outer shell– a huge body of salted water swirling around the moons rocky interior. New computer system modeling recommends the water might actually be pressing the ice shell along, possibly speeding up and slowing down the rotation of the moons icy shell gradually.
Researchers have known that Europas shell is most likely free-floating, rotating at a various rate than the ocean below and the rocky interior. The brand-new modeling is the first to show that Europas ocean currents might be adding to the rotation of its icy shell.

A crucial element of the study included calculating drag– the horizontal force that the moons ocean applies on the ice above it. The research mean how the power of the ocean flow and its drag versus the ice layer could even represent a few of the geology seen on Europas surface area. Cracks and ridges could result from the icy shell gradually collapsing and stretching gradually as it is pushed and tugged by the ocean currents.
NASAs Europa Clipper will swoop around Jupiter on an elliptical path, dipping near to its moon Europa on each flyby to collect information. Credit: NASA/JPL-Caltech
” Before this, it was known through lab experiments and modeling that cooling and heating of Europas ocean might drive currents,” said Hamish Hay, a researcher at the University of Oxford and lead author of the study released in JGR: Planets. Hay carried out the research while a postdoctoral research associate at NASAs Jet Propulsion Laboratory in Southern California. “Now our outcomes highlight a coupling in between the ocean and the rotation of the icy shell that was never previously thought about.”
It may even be possible, using measurements gathered by NASAs upcoming Europa Clipper mission, to figure out with precision how fast the icy shell turns. When scientists compare images gathered by Europa Clipper with those caught in the past by NASAs Galileo and Voyager objectives, they will have the ability to examine locations of ice surface functions and potentially figure out if the position of the moons icy shell has changed in time.
For decades, planetary researchers have discussed whether Europas icy shell might be rotating faster than the deep interior. Rather than connecting it to the oceans movement, researchers focused on an outdoors force: Jupiter. They theorized that as the gas giants gravity pulls on Europa, it also pulls on the moons shell and triggers it to spin slightly faster.
” To me, it was entirely unexpected that what takes place in the oceans blood circulation might be enough to impact the icy shell. That was a huge surprise,” said co-author and Europa Clipper Project Scientist Robert Pappalardo of JPL. “And the concept that the ridges and fractures we see on Europas surface could be tied to the blood circulation of the ocean below– geologists do not typically believe, Maybe its the ocean doing that.”.
Europa Clipper, now in its launch, test, and assembly operations phase at JPL, is set to introduce in 2024. The spacecraft will begin orbiting Jupiter in 2030, and will use its suite of sophisticated instruments to gather science data as it zips the moon about 50 times. The objective aims to determine if Europa, with its deep internal ocean, has conditions that could be suitable for life.
Like a Pot of Water.
Utilizing strategies established to study Earths ocean, the papers authors count on NASA supercomputers to make massive models of Europas ocean. They checked out the intricacies of how the water circulates, and how cooling and heating affects that motion.
Researchers believe that Europas internal ocean is heated up from below, due to radioactive decay and tidal heating within the moons rocky core. Like water heating in a pot on a range, Europas warm water increases to the top of the ocean.
In the simulations, the circulation at first moved vertically, however the rotation of the moon as a whole triggered the flowing water to divert in a more horizontal instructions– in west-east and east-west currents. The researchers, by including drag in their simulations, had the ability to identify that if the currents are quickly enough, there could be appropriate drag on the ice above to speed up or decrease the shells rotation speed. The quantity of interior heating– and thus, flow patterns in the ocean– may change over time, possibly accelerating or slowing rotation of the icy shell above.
” The work might be crucial in understanding how other ocean worlds rotation speeds might have altered with time,” Hay said. “And now that we understand about the prospective coupling of interior oceans with the surface areas of these bodies, we might discover more about their geological histories as well as Europas.”.
Recommendation: “Turbulent Drag at the Ice-Ocean Interface of Europa in Simulations of Rotating Convection: Implications for Nonsynchronous Rotation of the Ice Shell” by H. C. F. C. Hay, I. Fenty, R. T. Pappalardo and Y. Nakayama, 19 February 2023, JGR: Planets.DOI: 10.1029/ 2022JE007648.
More About the Mission.
The primary scientific aim of the Europa Clipper mission is to check out the possibility of life-sustaining environments below the icy surface of Jupiters moon, Europa. The objective focuses on three core objectives: examining the nature of the ice shell and the ocean below, in addition to their structure and geology. This extensive research study of Europa will improve scientists understanding of the astrobiological capacity of habitable worlds beyond Earth.
Caltech in Pasadena, California, handles the mission, with the development led by the Jet Propulsion Laboratory (JPL) in cooperation with Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, on behalf of NASAs Science Mission Directorate in Washington. APL, in collaboration with JPL and NASAs Goddard Space Flight Center in Greenbelt, Maryland, developed the primary spacecraft body. The Planetary Missions Program Office at NASAs Marshall Space Flight Center in Huntsville, Alabama, supervises the program management of the Europa Clipper objective.

The research study hints at how the power of the ocean flow and its drag against the ice layer might even account for some of the geology seen on Europas surface area.” Before this, it was understood through laboratory experiments and modeling that heating and cooling of Europas ocean might drive currents,” stated Hamish Hay, a scientist at the University of Oxford and lead author of the research study published in JGR: Planets. “And the idea that the ridges and fractures we see on Europas surface might be tied to the flow of the ocean below– geologists do not usually believe, Maybe its the ocean doing that.”.
The objective aims to identify if Europa, with its deep internal ocean, has conditions that might be ideal for life.
The main scientific objective of the Europa Clipper mission is to explore the possibility of life-sustaining environments below the icy surface of Jupiters moon, Europa.