An analysis has emerged that landslides are occurring on the moons orbiting Jupiter and Saturn, the largest planets in the solar system. The strong gravity of a large planet squeezes the satellites orbiting the planet and causes earthquakes, which means that high mountains often collapse and the terrain is flattened.
Researchers from the National Aeronautics and Space Administration (NASA) and the University of Arizona recently published analysis results of the surfaces of satellites orbiting Jupiter and Saturn in the latest issue of the international journal ‘Icarus’.
The research team paid attention to the satellites orbiting Jupiter and Saturn, which are the first and second in mass in the solar system. Unlike the satellites of other planets, the satellites of these planets, which have huge gravitational forces, have terrains that look like shallow valleys where high mountains have been crushed by some force. This phenomenon was prominent on Jupiter’s moons Europa and Ganymede, and Saturn’s moon Enceladus.
At first, the scientific community thought that these ‘strange’ features were caused by liquids seeping out of the earth’s surface. The scientific community believes that Europa, Ganymede, and Enceladus have a large underground ocean. The strong gravitational forces of Jupiter and Saturn rub against these moons, which causes the ice inside them to rub against itself and become water. It is hypothesized that this water leaked to the ground for some reason and flowed like a river. It is estimated that the result of this phenomenon looked like a valley.
However, the average temperature of these moons is between 160 and 200 degrees below zero. It’s incredibly cold. Even if water comes out to the ground in a liquid state, it is hard to flow for a long time because it is frozen solid. Because of this, it is a mystery how these unusual topography came to be.
The researchers found that earthquakes, or tectonic changes caused by the strong gravitational pull of Jupiter and Saturn, were the key. The researchers analyzed surface images of Europa, Ganymede, and Enceladus with a computer. And it was assumed that an earthquake of magnitude 4.0 to 7.9 occurred on the surface.
Then, numerous fragments scattered all over the surface of the satellite were observed in many places that matched the surrounding terrain like a puzzle. This means that an earthquake caused by the gravity of a giant planet is likely to have triggered a landslide.
Dr. Robert Pappalado of NASA’s Jet Propulsion Laboratory, who is part of the research team, explained in an official NASA presentation, “Through this study, we learned how powerful earthquakes on satellites can be.”
In the future, studies on earthquakes generated by these satellites are expected to accelerate further. The European Space Agency’s (ESA) space probe ‘Juice’ launched this month will observe Europa and Ganymede after arriving at Jupiter’s orbit in 2031. NASA will launch the space probe ‘Europa Clipper’ next year. The Europa Clipper will focus on exploring Europa after arriving in Jupiter’s orbit in 2030.
