Jupiter’s four largest moons in the order of distance from Jupiter: Ao, Europa, Ganymede and Kistlisto. Credit: NASA / JPL / DLR
Gravity push and pull through JupiterThe moon alone can record even higher temperatures than the gas giant Jupiter.
Jupiter’s moon is hot.
Well, to stay far away from the sun, they should be warmer than that. In a process known as tidal heating, gravitational tugs from Jupiter’s moon and the planet itself squeeze enough to pull the moon and warm it up. As a result, some icy moons have a warm enough interior to host oceans of liquid water, and in the case of rocky lunar ions, tidal heating rocks melt into magma.
Researchers had previously thought that the gas giant Jupiter was responsible for most of the tidal heat associated with the moon’s liquid interior, but a new study has been published. Geographical research papers It was found that lunar-lunar interactions may be more responsible for heat than Jupiter alone.
“It’s amazing because the moon is so much smaller than Jupiter. You wouldn’t expect them to be such a big recruiting response, ”said Hamish Hay, a postdoctoral fellow at Jet Propulsion Laboratory in Pasadena, California, who was a graduate student when he did the research. Arizona Lunar and Planetary Laboratory.
It is important to understand how the moon affects each other as it can shed light on the evolution of the entire lunar system. Jupiter has about 80 moons, of which the four largest are Io, Europa, Ganymede, and Call List.
Co-author Anthony Trinh said, “To maintain a subsurface ocean against cooling since geological time requires a fine balance between internal heat and heat loss, and yet we have many pieces of evidence that Europa, Ganymede, Callisto and other lunar oceans exist. Should. ” Postdoctoral research fellow at the Moon and Planetary Lab. “The Galilean moon Io, near Jupiter, shows extensive volcanic activity, another result of tidal heat, but at an intensification experienced by other planets like Earth in their early history. Ultimately, we want to understand all of these heat sources, for their influence on the evolution and habitat of the solar system and many worlds beyond it. “
Echo of the tide
The trick of tidal heating is a phenomenon called tidal echo.
“Echo loads generate more heat,” Hay said. “Basically, if you push an object object or system and let it go, it will shake at its own natural frequency. If you keep pushing the system at the right frequency, that oscillation gets bigger and bigger, just like when you are pushing the swing. If you push the swing at the right time, it goes further, but the time gets wrong and the speed of the swing weakens. “
The natural frequency of each moon depends on the depth of its ocean.
Haye said, “These tidal echoes were known before this work, but they were only known for tides because of Jupiter, which can only have an effect if it is really thin in the ocean (less than 300 meters or less than 1000 feet), which Impossible, ”Hay said. . “When tidal forces act on the global ocean, they create a tidal wave on the surface that propagates around the equator with a certain frequency or duration.”
According to researchers’ model Dell, the influence of Jupiter alone in its ratio with the Moon cannot produce tides with the right frequency because the Moon’s oceans are thought to be very thick. That’s when researchers added to another moon’s gravitational influence that they were beginning to see tidal forces approaching the moon’s natural frequency.
When the tides produced by other objects in Jupiter’s lunar system coincide with each moon’s own resonant frequency, the moon begins to feel warmer than the tides raised by Jupiter alone, and in extreme cases, this can cause ice to melt. . Or rock internally.
To experience the lunar tides, their oceans must be hundreds of kilometers – at least a few miles – thick, in the range of scientists’ current predictions. However, there are some caveats to the researchers ’findings.
His model Dell assumes that the tide of tide never overflows, Haye said. He and his team want to get back to this variable in the model and see what happens when they lift this barrier.
It is also hoped that future studies will be able to estimate the true depth of the oceans within this moon.
Reference: Hamish C.F.C. Hey, Antony Trinh and Isamu Matsuyama, 19 July 2020 by “Powering the Galilean Satellites with Moon – Moon Tides” Geographical research papers.
DOI: 10.1029 / 2020GL088317
Funding was provided through this study NASANo resident world program.
