Scientists may have identified an ocean hidden beneath the icy surface of Miranda, a small moon of Uranus. This unexpected discovery could change our understanding of icy worlds and revive the debate about the possibility of harboring life in our solar system.
Miranda, a small moon with complex geology
Mirandathe smallest and closest of Uranus' five large satellites, has astounded astronomers since the first images returned by the probe Voyager 2 In 1986. Although this frozen world only measures 233 km In diameter, its surface reveals a rich and complex geological past. Particularly revealing were the images sent by Voyager 2 Amazing features Such as vast craters and fault systems. These features provide evidence of tectonic activity that appears to have contributed to the formation of Miranda over millions of years.
The Southern Hemisphere, which can be seen during Voyager's flyby, features geological layers that indicate a history marked by periods of extreme stress. Replay. There we find an ancient, cratered unit covered by younger layers, indicating a geological resurfacing. These young formations, called coronas, are distinguished by their concentrated dark grooves that may have formed as a result of processes such as subduction or cryovolcanism. This therefore indicates internal movements of materials within the ice crust.
Recent studies have also shed light on The presence of ammonia (NH₃) on Miranda's surface, which is the element that denotes a Recent geological activity Because of its vulnerability to radiation. Therefore, this discovery raises questions about the geological processes currently occurring on this mysterious moon.
Possible underground ocean
In particular, scientists wonder whether Miranda could have shelter Underground oceanSimilar to those observed in other icy bodies in the solar system, such as Enceladus and Europa. If we believe this hypothesis, the geological activity observed on Miranda's surface could be a result of this Internal heating caused by tidal forces. In fact, Miranda's orbit around Uranus is affected by other moons, creating a resonance that can cause internal tensions.
To find out, a team from the Johns Hopkins Applied Physics Laboratory (APL) Recently analyzed The geological formations in Miranda's photographs were noted and computer models were used to reconstruct their history. Their goal? Understand why Miranda's surface exhibits trapezoidal fractures, ridges and crowns that defy simple geological explanations.
By testing different hypotheses in their model, the researchers then discovered that the only configuration that matched the observed configurations actually required the presence of an underground ocean. According to them, this ocean could be approx Thirty kilometers below the surface Frozen and can arrive Its depth reaches 100 kmThis is significant for a celestial body with a radius of only 235 kilometers.
What does this mean for the search for life
Clearly, the possibility of an underground ocean on Miranda raises interesting questions about life elsewhere in the solar system. If this ocean exists, it can provide a stable environment for… Microorganisms Similar to those that thrive in extreme environments on Earth, such as underwater volcanoes or icy plumes.
The next step for scientists will be to confirm whether this ocean exists or not. However, to achieve this, space missions will be needed to study Uranus and its moons in greater depth. This type of mission could include probes capable of closely analyzing Miranda's icy surface, or even drilling through the crust to reach underground layers.
Although this moon is not yet among the priority targets for future space missions, such a discovery could be a game-changer. Therefore, scientists hope that missions to Uranus and its icy moons will be included in the plans of NASA and other space agencies in the future.